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Oestrous Cycle Pharmacological Manipulation - Anatomy & Physiology (view source)
Revision as of 13:43, 12 September 2008
, 13:43, 12 September 2008→Prostaglandins
* Administration of PGF2α or its analogues will cause premature luteolysis of the corpus luteum.
* Administration of PGF2α or its analogues will cause premature luteolysis of the corpus luteum.
* This can be used to manipulate the normal pattern of cyclic activity.
* This can be used to manipulate the normal pattern of cyclic activity.
* Prostaglandins will induce luteal regression. As a result, progesterone levels fall and negative feedback on the anterior pituitary gland is removed. Subsequently, levels of gonadotrophins begin to rise, leading to increased follicular growth under the influence of FSH. Oestradiol production begins to rise as follicles become dominant. When oestradiol rises above the threshold, it feeds back positively at the level of the hypothalamus. The hypothalamus then releases a surge of GnRH. This then stimulates the anterior pituitary gland to release a surge of LH which is responsible for ovulation.
* The corpora lutea of the cow, mare, sow, ewe and goat respond to administration of exogenous prostaglandins.
* The corpora lutea of the cow, mare, sow, ewe and goat respond to administration of exogenous prostaglandins.
* In the cow, mare, ewe and goat the new developing corpus luteum is refractory to prostaglandins for 3-5 days after ovulation.
* In the cow, mare, ewe and goat the new developing corpus luteum is refractory to prostaglandins for 3-5 days after ovulation.