Inappropriate Elimination - Cat
Also known as: housesoiling
Introduction
House soiling is a common problem for owners. There are generally two types, inappropriate elimination and marking behaviour. It is important to differentiate between them to identify the route of the problem, but they can also be present concurrently. Any underlying medical conditions must also be ruled out.
General Aspects of Investigation of Housesoiling Cases
Medical Assessment
Medical factors are very important in housesoiling and marking problems. Certain conditions are directly involved in the generation and maintenance of behavioural problems, whilst others are contributory in an indirect sense [see box]. If a case is to be referred to a non-veterinary behaviourist, it is essential to rule out any potential underlying or contributory medical factor.
Medical factors underlying housesoiling problems |
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Conditions causing PU/PD: renal insufficiency, diabetes mellitus. |
Feline lower urinary tract disease. |
Diseases causing debilitation: osteoarthritis, senile dementia, and sensory loss. |
Diseases affecting cognition: senile dementia, CNS pathology [primary or secondary to systemic disease]. |
In any case of house soiling it is important to consider medical differentials before embarking on a purely behavioural assessment of the problem. Any condition which affects gastrointestinal or urinary tract function is a potential candidate for involvement in cases of inappropriate elimination and a full medical examination is therefore essential. Conditions which result in polydipsia and polyuria may also be implicated when urine deposits are found in unusual locations and endocrine disorders should be considered when investigating these cases. Any medical condition which alters the cat’s mobility may limit its ability to gain access to latrines, and conditions which alter the animal’s cognitive ability or sensory perception may also contribute to a breakdown in previously well-established house training. Organic disease may also be a factor in cases of undesirable marking behaviour.
The medical workup must include:
- Medical history
- Clinical examination – including abdominal palpation
- Urinalysis
- Assessment of mobility, cognitive function and sensory perception
- Further investigation through haematology, biochemistry or imaging techniques
Behavioural Assessment
Inappropriate elimination and indoor marking behaviour may be difficult to differentiate in some cases, and in many they occur together. It is important to collect all of the information needed to make a judgement:
- Age of onset
- Previous record of house training
- Present reaction to litter facilities
- Pattern of deposits – location, frequency, volume
- Orientation of deposits – onto vertical or horizontal surfaces
- Posture of cat during deposition
- Relationships between animals in the household
- Presence or absence of the owner or other animals around the time of soiling [including other cats seen outside].
- Owner’s reaction to the deposits
- Events in the household or the neighbourhood coinciding with the onset of the behaviour
- Assessment of the cat’s emotional reactions to novelty in the environment and to strangers
Using a House Plan
separate page? One of the most useful tools when investigating a problem of feline house soiling is a plan of the house in which the cat lives. This does not need to be a detailed scale drawing but rather a basic plan indicating the layout of rooms in the house, the position of windows, doors and major furniture and the location of major resources such as feeding and watering stations, sleeping locations and play areas. Each individual cat’s favourite resting places and rooms they prefer to inhabit should be noted on the diagram. The client should mark onto this diagram the location of urine and faeces that they have found. [see figure]
To give a better indication of the development of the problem, the client should note the current frequency of urine/faecal deposition at a particular site, as well as how early in the development of the problem urine or faeces were first found there. A convenient way to do this is to label each location on the diagram with a number of stars to indicate current frequency and a number that indicates whether that spot was one of the first, or last places to be soiled, or somewhere in between. The clinician may use this diagram [see example] as a basis for recording additional information about each mark, such as the volume of urine at a site, where precisely on furniture or decorations it is located and whether any particular event appears connected to it.
The pattern of urine and faecal deposits can point to the source of the problem. For example, if the first deposits were found close to doors and windows, it is suggestive that the perceived threat was coming from outside the home whilst initial deposits in the centre of rooms or onto new pieces of furniture would suggest that the disruption of the cat’s security was coming from within the household.
Once all of this information has been collected, it is then possible to make judgements about the nature of the problem, whether it is a matter of indoor marking or elimination and what the motivation may be.
Differentiating Between Elimination and Marking
Once full information has been collected about the location and characteristics of each urine or faecal deposit, it is possible to differentiate between its cause.
Positioning of Deposits and Reaction to the Litter Tray
In the case of marking, the areas that the cat uses to deposit urine or faeces will often be of behavioural significance, for example areas that smell of the owner or of the new cat in the household or locations which are associated with potential threat from the outside world. There is often a provoking stimulus for this inappropriate behaviour such as some disruption to the home environment or competition within the local neighbourhood and the location of the marking deposits will reflect this. Urine or faecal marks are placed strategically in order to provide a signal to other cats, which means that they must be placed in locations that are likely to be noticed. The act of spraying itself also involves an element of visual display. It should be remembered that odour marks are not merely of use to the ‘sender’ of the signal, who is trying to maintain distance from other cats. They are also of use to the ‘receiver’, who is equally keen to avoid direct physical conflict. The location of scent marks therefore follows conventions that allow other cats to find and investigate them easily. Such places might include on door frames, or on doors, or on pieces of furniture that face doors or windows.
Inappropriate indoor elimination, on the other hand, will usually take place in quiet secluded locations which reflect the sort of places which cats would naturally choose to use as latrines. It is also likely that elimination sites will have certain common characteristics in terms of the substrate that is used and cats will often develop preferences for the inappropriate substrate, such as carpet or linen, and return to similar surfaces repeatedly. These inappropriate substrates may be similar to those the cat was forced to use as a kitten, through an inadequate provision of proper latrines in the rearing environment.
One useful difference between indoor ‘markers’ and ‘toileters’ is their reaction to the indoor latrine facilities, with ‘markers’ often continuing to use the litter tray and ‘toileters’ actively avoiding the facilities provided. Indeed, in cases of a lack of, or a breakdown of house-training, signs of aversion to the litter tray may be the first thing that the owner notices.
Cats with lower urinary tract disease will often use several different sites in the house during the same period, breaking the usual pattern of the cat using only one or two latrines. This is because pain associated with micturition in each of the latrine sites discourages repeated use of the same locations. The cat associates eliminating in that place with pain or dysuria and chooses somewhere else next time. Amounts of urine found at each site may be smaller then normal and have a strong odour or contain blood. This pattern of urination is often cyclical, with cats eliminating normally for a few weeks and then suffering another bout of generalised housesoiling. This fits with the cyclical nature of the severity of lower urinary tract disease, which may wax and wane.
Frequency of Deposits
If a cat is depositing urine and faeces, as part of the normal function of elimination, the frequency will reflect this and deposits will be limited in their number. However, when cats are using the deposits as a form of marking there is no limit on the frequency of deposition and it is not unusual for a urine spraying cat to leave in excess of thirty marks within the home in a 24-hour period.
Volume of Deposits
The amount of urine that is deposited can also help to determine the motivation for the behaviour with toileting problems usually involving larger quantities than marking problems. However, this can be confusing since a small amount of urine can be absorbed by carpets and other fabrics and the size of the moist patch on the floor can be misleading! Cats with FLUTD will pass many small quantities of urine in several sites, causing confusion with a marking problem. Likewise, cats with chronic diarrhoea. However, the choice of location will still fit with normal defaecation or urination.
Posture of Cat and Orientation of Deposits
The posture of the cat can help in the differentiation process, since indoor urine spraying is usually associated with a characteristic stance. This is related to the function of the marking behaviour since a standing posture allows the cat to deposit urine on a vertical surface at just the correct height for another cat to sniff at it and take in the important information.
However, urine marking does not exclusively occur from a standing posture and it can be performed from a squatting position, which closely resembles the posture adopted during the act of elimination. This fact must be borne in mind when attempting to differentiate between motivations as it is easy to dismiss squatting urination on horizontal surfaces as always being eliminative and yet there are occasions when the cat is actually using that sort of urination as a marking behaviour.
Pattern of Urine and Faeces Deposition [identified using a house plan]
Certain patterns are classic indicators of a specific underlying motivation. For example, if the first urine marking deposits were found close to external doors and windows it is suggestive that the perceived threat was coming from outside the home, whilst initial deposits in the centre of rooms, corridors or staircases, or onto new pieces of furniture would suggest that the disruption of the cat’s security was coming from within the household. As a situation progresses, the pattern becomes more confusing so that it becomes very difficult to identify the originating cause unless the historical development of the pattern of the marking or elimination is known. For example, urine marking may progress from door and window areas to hallways and rooms if a neighbourhood despot begins to invade the resident cat’s home.
Indoor Marking | Indoor Elimination | |
Characteristic patterns in urine and faeces deposition: |
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Behaviour and Posture: |
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Deposit: |
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Location: |
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Organic Disease
In any case of house soiling it is important to consider medical differentials before embarking on a purely behavioural assessment of the problem. Any condition which affects gastrointestinal or urinary tract function is a potential candidate for involvement in cases of inappropriate elimination and a full medical examination is therefore essential. Conditions which result in polydipsia and polyuria may also be implicated when urine deposits are found in unusual locations and endocrine disorders should be considered when investigating these cases. Any medical condition which alters the cat’s mobility may limit its ability to gain access to latrines, and conditions which alter the animal’s cognitive ability or sensory perception may also contribute to a breakdown in previously well-established house training. Organic disease may also be a factor in cases of undesirable marking behaviour.
Emotional Factors
In situations of both marking and elimination behaviour within the home, it is important to assess the cat’s emotional status and to attempt to identify any triggers for alteration in that status. Perception of threat either from within or outside the home is commonly associated with the onset of marking behaviour but it is also important to remember that cats that are feeling threatened and insecure may be reluctant to use litter facilities that are positioned in vulnerable locations or that pose difficulties for the cat in terms of competition with other feline household members. In general, it is the insecure and timid feline that is more likely to present with problems of marking behaviour and individuals that do not cope well with change in their environment are going to be predisposed to the use of urine deposits that are designed to increase home security. In addition, cats that are living in a hostile social environment, where there is underlying tension between feline housemates, may use marking behaviour in an attempt to increase distance between them and to avoid overt physical confrontation. Therefore, an assessment of the compatibility between cats in the household is an important part of the investigation process. Likewise, the relationship between the cat and the owner should be considered and questions about the owner’s reaction to the discovery of deposits within the home should be included in the consultation. It is perfectly understandable for people to find it unacceptable that their pet is depositing urine or faeces within their home but the use of punitive techniques may be a factor in perpetuating the behaviour and confirming the cat’s perception that the house is no longer a secure core territory.
Owners often misinterpret relationships between cats in multi-cat households because they are unaware of the significance of certain behaviours. For example, cats will often be described as ‘getting on well’ because they eat and rest in proximity to one another on the owner’s bed or couch. Unfortunately, this apparent tolerance may exist only because the cats are forced to be close to each other when they are feeding or resting. They have no other choice because there are no other feeding stations or equivalent resting places. The cats may be very wary and hesitant whilst feeding and the owner will report that there are frequent bouts of hissing or spitting around the food bowl. Likewise, as one cat leaves a resting place or feeding area, it may be pursued or attacked and cats may attempt long distance intimidations, such as staring eye contact, to frighten each other away from resting places or latrines. Some cats will try to pull food out of a dish with their paws so that they can take it to eat in private. The same desire for privacy will drive them to make a toilet of their own somewhere in the house.
It is important to make a formal assessment of the relationships between cats in the household. A diagram should be constructed to illustrate the relationships. The social function of cats that have died or been re-homed may be important so it may be necessary to draw more than one diagram to illustrate the changing relationships as cats have departed or been added to the group.
Positive affiliative reactions that should be noted include allorubbing and allogrooming, tail up and trilled greeting between cats. Aggressive behaviours include active threats such as chasing, hissing or spitting and physical attacks, as well as more passive or distant threats such as staring eye contact, threatening body or facial posture, or spraying in front of other cats. These classes of behaviour and their direction should be noted on a diagram of interactions, as illustrated in the figure below.
This may enable certain factions to be identified within the household. Combined with the information already obtained about where cats spend most of their time in the household, this makes the allocation of resources easier during treatment. It may also help to identify feline despots. Making an assessment of this kind is important even when looking at a multi-cat household with what appears to be reactionary spraying due to conflict with outside cats. If resources in the home are sparse, then certain cats may perceive there to be a local overpopulation problem which is made worse by competition with outside cats. Sorting out internal conflict is likely to improve the cats’ general welfare as well as help to resolve elimination and marking problems.
ELIMINATION
Once the initial history taking has been completed and the case has been categorised as one of elimination, it is important to spend time investigating the potential trigger factors which lead to the onset of the behaviour. Only once the underlying reasons for the alteration in toileting behaviour have been identified can effective behavioural therapy be instituted and the cat taught to return to more acceptable patterns of elimination.
In some cases, the cat may never have achieved a state of successful house training but these are relatively uncommon. In the past, a belief that kittens needed to observe their mother’s eliminatory behaviour in order to learn how to toilet appropriately was thought to be supported by the over representation of certain breeds, such as Persians, and the occurrence of house soiling issues within familial lines in those breeds. However, research suggests that observational learning is not involved in this process and that a lack of opportunity to explore and experiment with suitable substrates early in life is more likely to influence a failure to house train successfully. Obviously this access to suitable litter is going to be influenced by the mother’s behaviour since kittens will follow her when she goes to use the tray and will thereby come into contact with an acceptable substrate. Kittens from mothers with poor toileting skills are therefore likely to have less interaction with a suitable substrate and may develop problems as a result but, even when the mother is a very clean individual, lack of suitable facilities near to the nest will have a similar effect. Failure to provide suitable substrate can also lead to the development of undesirable substrate associations.
COMMON
Diagnosis
Identifying the Culprit
It is very important to properly identify the culprit[s] for the indoor housesoiling. Clients frequently blame a particular animal, usually because they have seen it eliminating in the house. However, other cats may also be involved. It is possible to use fluorescein dye to identify the urine of each cat in the household so that the identity of the soiling cat can be confirmed [see box below]. Recent research has shown that the fluorescence of urine spots from fluorescein treated cats may vary with urine pH. The fluorescence of fluorescein varies with pH, such that it only strongly emits light under UV illumination when it is in a neutral or alkaline solution. In acidic solution it may hardly glow green at all. Spots should therefore be sprayed with a buffer solution of sodium bicarbonate [baking soda], which will produce a pH of around 8, before testing with a UV lamp. If faecal soiling is involved, then a small amount of indigestible material is added to each cat’s food for several days and the faeces are inspected. Crushed sweet corn works very well because it is easy to identify in the faeces and does not upset digestion.
Using Fluorescein to Identify Urine Marking or Soiling Cats
- Fluorescein is available as sterile paper strips, for ophthalmic examination. These contain approximately 1 mg of fluorescein per tip, but this should be checked with the manufacturer.
- The tips should be torn off and rolled to fit into gelatine capsules, giving approximately 5 per capsule [5mg].
- This dose is given once daily for 3-4 days.
- Urine sites are checked daily.
- Lightly spray each site with a solution of sodium bicarbonate [baking powder], mixed in water [1 tablespoonful in 125ml water].
- A UV lamp is then used to check the site for fluorescence.
- It is vital to start by testing the least probable culprits first, working up to the most probable. Otherwise fluorescence marks left by one cat will obscure those of another. If it is certain that the culprit is a resident cat then the culprit may be identified by a process of elimination, which minimises the risk of leaving lots of fluorescent stains for the client to
clean up.
- A 5-day washout is left between testing of each cat, to make sure that each individual has excreted all of the dye before testing the next.
- Although fluorescein is water-soluble and can usually be removed with normal cleaning, this testing method may leave stains on fabric, carpets or wall paper and owners must be warned of this.
ELIMINATION
Behavioural Diagnosis
A behavioural diagnosis should only be attempted after medical underlying and contributory factors have been investigated. A diagnosis is reached after collecting a detailed history and making diagrams of the soiling locations. Causes of housetraining breakdown are many and varied and detailed history taking and in-depth consultations are essential to get an accurate picture. Post trauma breakdown is relatively common and examples of trauma can include a period of enforced confinement, fear of the litter tray due to administration of medication or negative associations with the tray as a result of medical problems. Inappropriate facilities may be at the root of inappropriate toileting problems and it is important to consider the type of litter used in the tray, the sort of tray that is being offered and also the location of that tray. The cleaning regime may also be relevant since most cats are reluctant to use trays that are dirty and some others will fail to bond successfully to their latrine if it is cleaned too frequently. Other potential causes of a breakdown in house training include challenges to security in nervous individuals, overcrowding within a small-sized territory where there is competition over the resource of the latrines or access to the trays is controlled and manipulated by one individual within the household. There is also the issue of old age and debilitation.
ELIMINATION
Typical Causes
- Lack of privacy in latrine locations: litter trays that are placed too close to feeding areas or cat doors, or sited in busy places where the cat does not feel safe to go to the toilet. A previously satisfactory location may become unacceptable if the presence of new pets or children constantly disturbs the cat. New cats in the neighbourhood may overlook the litter tray from outside, again reducing privacy.
- Inappropriate substrate: Certain scented, pine or wood-pulp based litters are aversive to cats. When urinated on they may release odours that the cat finds repellent, especially if the litter tray is hooded or enclosed. Substrate depth is also important, with cats preferring a depth of around 3cm.
- Competition and excessive latrine use: if several cats are using the same litter tray then it quickly becomes soiled and cats may be forced to find somewhere else. Cats may be forced to displace each other in order to gain access to the solitary household latrine. Cats prefer to use separate toilets for urine and faeces wherever possible.
- Despotic control of entry/exit points: Feline despots may perch close to cat doors and threaten other cats as they come and go. Nervous cats may not have the confidence to go in and out so they cannot use outdoor latrines. Threatening of cats leaving or entering the litter tray may also occur from cats within the same household.
- Specific fears: Cats that are moved to a noisy or stressful location may be unwilling to go outside to use latrines. They may stay inside and soil the house if not provided with a litter tray.
- Negative litter box associations: If the cat has been attacked or disturbed whilst using a particular latrine, or if it has experienced pain on micturition, then it is likely to chose a different toilet location the next time it needs to eliminate.
- Inability to use/find litter trays: Elderly or debilitated cats may be less willing to travel to find a latrine, so they may resort to soiling in the house. They may be unable to make use of high-sided or covered trays.
- Medical illness: Cats with PU/PD, incontinence, FLUTD or recurrent/chronic diarrhoea are unlikely to maintain a normal or acceptable pattern of elimination.
- Punishment: cats that have been punished for eliminating in the wrong place may refuse to go to the toilet in the presence of the owner. Litter trays tend to be placed in public areas like the kitchen or utility area, which means that the fearful cat ceases to use them for fear of being punished further.
CYSTITIS Recent research has demonstrated a direct connection between psychosocial stress and feline lower urinary tract disease. Feline idiopathic cystitis [FIC] is a complex condition that involves neurological changes in spinal pain fibres and biochemical changes in the bladder wall. The precise aetiology is not fully understood but cats with an anxious personality are predisposed to FIC and it is proposed that the condition arises from a combination of physical and psychological factors. Black and white cats, and Persian cats are commonly affected and FIC may account for a significant proportion of FLUTD in cats. Urine samples of FIC cats may be sterile or may contain crystals, plugs or traces of blood. Diagnosis is confirmed by double contrast radiography or ultrasound imaging of the bladder to reveal mural thickening.
Treatment
ELIMINATION
Medical aspects of elimination problems must be resolved. There is a close relationship between stress and FIC so that dealing with social and environmental stress is an important component in resolving this condition.
HOUSESOILING Typically, it is possible to identify one or two environmental changes that have initiated the housesoiling problem. This may be something as simple as a change of cat litter. However, it is very important not to treat the problem at this superficial level. If a single inconsequential change has caused the cat to house-soil then it is very likely that there are other underlying problems that also need to be addressed. Not to do so may mean consigning the cat to a life of stress and impaired welfare.
Treatment of housesoiling, therefore, involves dealing with general environmental and social issues that cause stress, as well as the specific aspects of latrine location and type. Aggression between cats sharing a household is often overlooked because actual fights may be uncommon and most of the threatening behaviours between them are subtle.
Overall resource levels should be increased and resources should be distributed so that individual cats and cat-factions can make use of them without coming into conflict with each other. This also helps to undermine the activities of feline despots who try to monopolise specific resources. Additional cat flaps may be needed if aggression between cats is preventing certain cats from using outdoor latrines.
The cats should be provided with a range of suitable latrines, inside and outside the house. Cats do not share latrine facilities so, in multi-cat households, the optimum number of latrines should be one per cat plus one extra. This number of cat litter trays is obviously a horrific prospect for the owner of a lot of cats. The answer is to provide cats with outdoor latrines in the owner’s garden. With the current fashion for hard landscaping, cats may have few opportunities to use good outdoor latrines and may have to travel across several gardens to find somewhere suitable. In winter, these toilets may become sodden or frozen, making them unusable. For this reason, many housesoiling problems are worse during the winter.
Outdoor latrines are actually very easy to construct. These outdoor toilets should be hidden in flowerbeds behind shrubs and tall plants to give the cat privacy. These latrines are essentially self-cleaning but it is sensible to regularly use a litter scoop to remove faeces in the same way as with a conventional litter tray. The sandy part of the latrine should be dug out and replaced every six months. One outdoor latrine is unlikely to be enough, and different cats will have different preferences for location. At least two latrines should be provided.
There are often concerns that other cats will come into the territory to use the outdoor latrines. This is a possibility but rarely causes a problem. In fact, the presence of nearby latrines tends to strengthen the boundary of the resident cat’s own territory.
Indoor latrines should be made as appealing as possible. They should be positioned in quiet locations and deep filled with a scent free mineral based litter. In some cases, soft sand or a mixture of soft sand and litter is attractive to cats, and the sand content can be reduced gradually once the cat has shifted its location preference to the designated litter tray.
F3 diffusers are traditionally used to treat spraying problems, but can be used to make a latrine location more attractive. The diffuser is placed very close to the litter tray in a confined area. This can be effective for cats that choose to eliminate on piles of the owner’s clothing or on the owner’s bed because these locations are associated with increased security. F3 diffusers may also be used to reduce general social stress in the household. In this situation, the diffuser should be allowed to warm up for at least a couple of hours before allowing cats to have access to the room where the diffuser is installed.
Conversely, inappropriate latrine sites should be made less appealing. There are a number of ways to do this, including changing the floor substrate to make it less pleasant to stand on, placing small bowls of food close to the location so that it becomes designated as a feeding station instead of a latrine. The best guide for how to modify a particular latrine site is the cat’s reason for choosing it in the first place. For example, a dark and secluded corner can be made a lot less discrete by moving furniture, putting in a loud radio close by or illuminating the corner with a bright spot lamp. Battery powered infra-red activated lamps can be bought very cheaply from hardware stores and can be installed in small corner, where it will switch on every time the cat approaches. This can act as an effective deterrent.
Altering inappropriate latrine sites to make them less appealing to the cat (this must only be done when a potential alternative has been made available)
- Cover the location with thick polythene: urine will then drain towards the cat’s feet when it is standing on the sheet.
- Cover the location with a large sheet of silver foil: some cats do not like to stand on this.
- Apply strips of double-sided sticky tape to either of the above to make them even more repellent.
- Place small bowls of food on top of the latrine sites, so that they become feeding stations. Cats are usually reluctant to urinate near sources of food.
- Illuminate dark corners with a bright spot lamp so that any privacy is taken away.
- The same effect can be achieved using a small, battery powered infrared activated lamp, which will turn on each time the cat approaches [these are very inexpensive].
Cats that are inhibited, fearful and therefore unable to utilise improved resources because of their apprehension, may benefit from psychoactive drug therapy. Selegiline is not licensed for use in the cat, but it can be used for the treatment of specific fears, a condition for which it is licensed in the dog (in the UK). This drug increases confidence and exploratory behaviour, but takes 4-6 weeks to show efficacy. It should be continued until the cat is fully utilising resources and has not eliminated in the house for 8 weeks.
Where signs of chronic anxiety are apparent, despite the use of F3 diffusers, then an SRI or SSRI type drug, such as Clomipramine or Fluoxetine, may be appropriate.
CYSTITIS Trial treatments for Feline Idiopathic Cystitis have included polysulphated glycosaminoglycans and Amitriptyline. Response to glycosaminoglycans was variable, with some individuals responding extremely well and others less so. Treatment with Amitriptyline has produced good results, with the affects being attributed to the nor-adrenergic effects of the drug. Amitriptyline is 5:1 selective in favour of nor-adrenaline over serotonin reuptake inhibition, whereas Clomipramine is 5:1 selective in favour of serotonin reuptake. However, both drugs do have significant effects on nor-adrenaline reuptake and Clomipramine may be a suitable alternative if there are concerns over adverse effects with Amitriptyline.
In all cases, psychoactive drug therapy should only be considered after reaching a specific diagnosis and taking into account the risks of disinhibition of aggression. Obstructive urinary tract disease should be ruled out before initiating therapy with SRI or SSRI drugs, which have a risk of increasing outflow obstructions through their effects on acetylcholine transmission.
This article is still under construction. |