Changes

 

==Introduction==

==Introduction==

Reproductive hormones often have multiple roles and operate via [[Negative_Feedback_-_Anatomy_%26_Physiology|negative feedback systems]]. The information below will provide the main reproductive hormones in domestic species and their functions.

Reproductive hormones often have multiple roles and operate via [[Negative_Feedback_-_Anatomy_%26_Physiology|negative feedback systems]]. The information below will provide the main reproductive hormones in domestic species and their functions.

<br />

<br />

<br />

<br />

Although the hypothalamus via GnRH stimulates the secretion of LH and FSH, it cannot regulate LH and FSH independantly. Therefore another hormone produced from the developing ovarian follicle in the female and sertoli cells in the male acts as a negative feedback mechanism for FSH. Sex hormones also alter the level of production of GnRH from the hypothalamus via a negative feedback system. High concentrations of progesterone or testosterone will reduce the secretion of GnRH and also therefore the secretion of LH and FSH.

Although the hypothalamus via GnRH stimulates the secretion of LH and FSH, it cannot regulate LH and FSH independently. Therefore another hormone produced from the developing ovarian follicle in the female and sertoli cells in the male acts as a negative feedback mechanism for FSH. Sex hormones also alter the level of production of GnRH from the hypothalamus via a negative feedback system. High concentrations of progesterone or testosterone will reduce the secretion of GnRH and also therefore the secretion of LH and FSH.

===Luteinising Hormone (LH)===

===Luteinising Hormone (LH)===

<br />

<br />

<br />

<br />

Normally the concentration of PGF_2α in arterial blood is relatively low due to extensive metabolism by PGF_2α-dehydrogenase in especially the lungs). These levels are below the threshold required to cause luteolysis as PGF_2α production in early gestation is low.

Normally the concentration of PGF_2α in arterial blood is relatively low due to extensive metabolism by PGF_2α-dehydrogenase (in especially the lungs). These levels are below the threshold required to cause luteolysis as PGF_2α production in early gestation is low.

<br />

<br />

<br />

<br />

The  [[Ovary_-_Anatomy_%26_Physiology#Arterial_Supply|ovarian artery]] is wrapped around the uterine vein. This creates a countercurrent mechanism by which the lipid soluable prostaglandins are able to diffuse from the uterine vein into the [[Ovary_-_Anatomy_%26_Physiology#Arterial_Supply|ovarian artery]]. During the latter stages of the [[Oestrous_Cycle_-_Anatomy_%26_Physiology|luteal phase]] as PGF_2α production increases luteolysis will occur as PGF_2α Is able to reach its target in the ovary before being metabolized in systemic circulation.

The  [[Ovary_-_Anatomy_%26_Physiology#Arterial_Supply|ovarian artery]] is wrapped around the uterine vein. This creates a countercurrent mechanism by which the lipid soluable prostaglandins are able to diffuse from the uterine vein into the [[Ovary_-_Anatomy_%26_Physiology#Arterial_Supply|ovarian artery]]. During the latter stages of the [[Oestrous_Cycle_-_Anatomy_%26_Physiology|luteal phase]] as PGF_2α production increases luteolysis will occur as PGF_2α Is able to reach its target in the ovary before being metabolized in systemic circulation.

===Prostaglandin (PGE₂)===

===Prostaglandin (PGE₂)===

[[Category:To Do - Review]]

[[Category:To Do - Review]]

[[Category:Reproductive System - Anatomy & Physiology]]

[[Category:Reproductive System - Anatomy & Physiology]]