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Parturition Endocrine Control - Anatomy & Physiology (view source)
Revision as of 12:20, 21 July 2008
, 12:20, 21 July 2008→Onset of Parturition
== Species that depend on the Corpus Luteum to produce progesterone throughout pregnancy (Goat, Cow, Sow, Bitch) ==
* The foetus initiates parturition.
* The foetus initiates parturition.
* For parturition to occur, progesterone production by the Corpus Luteum must be terminated.
* For parturition to occur, progesterone production by the Corpus Luteum must be terminated.
== Species that depend on Placental Progesterone in late pregnancy (Ewe,Guinea Pig,Queen,Mare) ==
* As previously explained, parturition is dependent on a rise in foetal Cortisol. However, in this case, the rise in foetal cortisol leads to a decrease in '''maternal''' Progesterone.
* As previously explained, parturition is dependent on a rise in foetal Cortisol. However, in this case, the rise in foetal cortisol leads to a decrease in '''maternal''' Progesterone.
* Foetal Cortisol causes upregulation of the enzymes '''17α Hydroxylase, C17-C20-lyase and Aromatase''' in order to increase the Oestrogen:Progesterone ratio.
* Foetal Cortisol causes upregulation of the enzymes '''17α Hydroxylase, C17-C20-lyase and Aromatase''' in order to increase the Oestrogen:Progesterone ratio.