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Parturition Endocrine Control - Anatomy & Physiology (view source)
Revision as of 09:46, 9 July 2008
, 09:46, 9 July 2008no edit summary
* Oxytocin release causes further synthesis and secretion of oxytocin, thus exibiting positive feedback.
* Oxytocin release causes further synthesis and secretion of oxytocin, thus exibiting positive feedback.
* Oxytocin concentrations continue to rise until the foetus is expelled, thus the cervical stimulation ceases.
* Oxytocin concentrations continue to rise until the foetus is expelled, thus the cervical stimulation ceases.
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== Role of Relaxin ==
* Glycoprotein hormone
* Produced by either the corpus luteum or placenta depending on species.
* Synthesis is stimulated by '''PGF2α'''
* Causes softening of the connective tissue in the [[Female_Reproductive_Tract_-The_Cervix_-_Anatomy_%26_Physiology|cervix]].
* Promotes elasticity of pelvic ligaments.
* Prepares the birth canal by loosening supportive tissues so that the passage of the foetus can occur with relative ease.
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== Role of Oestrodiol Elevation prior to Parturition ==
* Initiates secretory activity of the reproductive trace, particularly the [[Female_Reproductive_Tract_-The_Cervix_-_Anatomy_%26_Physiology|cervix]].
* Causes the cervix and vagina to produce mucus.
** Washes out the cervical seal of pregnancy.
** Lubricates the cervical canal and vagina
** Reduces friction, enabling the foetus to exit the reproductive tract with relative ease.
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* 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.