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Neurotransmitters - Anatomy & Physiology (view source)
Revision as of 13:57, 23 August 2011
, 13:57, 23 August 2011→Neuropeptides
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Endorphins and enkephalins are both examples of '''opioids''' and act within neuronal synapses to reduce the sensation of pain and in humans, it has been shown that these neuropeptides also lead to a sense of euphoria. Both of these molecules belong to the same opioid category as morphine and heroin.
Endorphins and enkephalins are both examples of '''opioids''' and act within neuronal synapses to reduce the sensation of pain and in humans, it has been shown that these neuropeptides also lead to a sense of euphoria. Both of these molecules belong to the same opioid category as morphine and heroin.
===Other Types of Neurotransmitter===
In many neuronal synapses, not only do the post-synaptic membranes contain receptors for neurotransmitters, they also contain ion channels. In many cases the neurotransmitter receptors and ion channels are directly linked giving rise to '''ionotropic receptors'''. When a neurotransmitter binds it's relevant receptor, this also may open affect the gating of adjacent ion channels, either opening or closing the channel. Ionotrophic receptors such as this are responsible for the fastest type of synaptic transmission. An example of an ionotrophic receptor is '''zinc''' which is synaptically released via this mechanism.
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Other ion channel receptors also exist in which the ion channel is less well associated with the neurotransmitter receptors. This type of ion channel receptor are referred to as '''metabotrophic receptors''' and are affected indirectly via '''G-proteins''' or '''intracellular secondary messengers''' altering the status of the gate once an appropriate signal has been received. Despite relying on a intermediate messenger system, metabotrophic receptors can also propagate rapid signal transfers, although not as rapid as ionotrophic receptors.
==Function==
==Function==