Expression of RFamide-Related Peptide-3 (RFRP-3) mRNA in Dorsomedial Hypothalamic Nucleus and KiSS-1 mRNA in Arcuate Nucleus of Rat during Pregnancy.
BACKGROUND
RFamide-related peptide-3 (RFRP-3) and kisspeptin (KiSS-1) are known to respectively inhibit and stimulate gonadotropin releasing hormone (GnRH) and lute- inizing hormone (LH) secretion in rat. The aim of the present study was to evaluate the relative mRNA expression of RFRP-3 and KiSS-1 in the hypothalamus of pregnant rats.


METHODS
In a randomized controlled experimental study, the exact preg- nancy day of 18 Sprague-Dawley rats were confirmed using the vaginal smear method and were equally assigned to three groups of days 7, 14 and 21 of pregnancy. Four non- pregnant female rats were ovariectomized and assigned as the control group. All rats were decapitated, and the dorsomedial hypothalamic nucleus (DMH) and the arcuate nucleus (ARC) for detection of KiSS-1 mRNA were separated from their hypothalamus to detect RFRP-3 and KiSS-1 mRNA respectively. Then, their relative expressions were compared between control and pregnant groups using real-time polymerase chain reac- tion (PCR).


RESULTS
The relative expression of RFRP-3 mRNA in DMH did not change significantly during pregnancy (p>0.01). However, the relative expression of KiSS-1 mRNA in ARC was at its highest in day 7 of pregnancy and decreased until day 21 of pregnancy (p<0.01).


CONCLUSIONS
Decrease in GnRH and LH secretion during the pregnancy of rat may be controlled by constant expression of RFRP-3 mRNA and reduced expression of KiSS-1 mRNA in hypothalamus.
Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Fatemeh
F
Sabet Sarvestani
Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran ; Infertility Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Amin
A
Tamadon
Laboratory Animal Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Omid
O
Koohi-Hosseinabadi
Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Saeed
S
Mohammadi Nezhad
Department of Basic Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran.
Farhad
F
Rahmanifar
Department of Animal Sciences, School of Agriculture, Shiraz University, Shiraz, Iran.
Mohammad Reza
MR
Jafarzadeh Shirazi
Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran ; Department of Pharmacology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
Nader
N
Tanideh
Biotechnology Institute, College of Agriculture, Shiraz University, Shiraz, Iran.
Ali
A
Moghadam
Biotechnology Institute, College of Agriculture, Shiraz University, Shiraz, Iran.
Ali
A
Niazi
Arcuate Nucleus; Dorsomedial Hypothalamic Nucleus; KiSS-1; Pregnancy; RFamide-Related Peptide-3