Physiology and Pharmacology
Physiol Pharmacol
Medical Sciences
http://ppj.phypha.ir
32
journal32
24765236
24765244
10.22034
(previous ISSN: 17350581)
en
jalali
1390
1
1
gregorian
2011
4
1
15
1
online
1
fulltext
en
Expression of gonadotropin inhibitory hormone in the preoptic area and its relation with phases of estrous cycle of ewe
Endocrine Physiology/Pharmacology
Endocrine Physiology/Pharmacology
Experimental research article
Experimental research article
Introduction: Gonadotropin inhibitory hormone (GnIH) has been known as a key inhibitor of the secretion of
gonadotropin releasing hormone (GnRH). Ewe has estrous cycles comprising of follicular and luteal phases. Follicular
phase is in turn divided into proestrous and estrous phases. Blood level of LH increases in follicular and decreases in
luteal phases. The aim of the present study was to evaluate (1) the presence of GnIH neurons in the ewe preoptic area
(POA) and (2) the alterations of GnIH expression during different phases of ewe estrous cycle.
Methods: Three fertile three-year-old ewes in each phase (n=9) were selected and the number of GnIH neurons was
estimated by using immunohistochemistry method.
Results: GnIH neurons were present in the POA during different phases of estrous cycle. The number of GnIH
neurons significantly increased in the luteal phase in comparison with the proestrous phase (P=0.001).
Conclusion: GnIH expression in the neurons of POA of ewe is increased in the luteal phase compared to the
follicular phase. This can inhibit GnRH secretion in POA and reduce LH secretion during the luteal phase.
Key words: Gonadotropin inhibitory hormone, Estrous cycle, Preoptic area, Ewe.
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http://ppj.phypha.ir/browse.php?a_code=A-10-393-2&slc_lang=en&sid=1
Mohammad Reza
Jafarzadeh Shirazi
mrjaafarzadeh@yahoo.com
320031947532846008892
320031947532846008892
No
Department of Animal Sciences, School of Agriculture, Shiraz University, Shiraz, Iran
Mohammad Reza
Namavar
namavarm@sums.ac.ir
320031947532846008893
320031947532846008893
No
Department of Anatomical Sciences, School of Medicine & Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
Amin
Tamadon
tamadon@shirazu.ac.ir
320031947532846008894
320031947532846008894
Yes
Stem Cell and Transgenic Technology Research Center, Shiraz University of Medical Sciences & Department of Animal Health Management, School of Veterinary Medicine, Shiraz University, Shiraz, Iran