چكيده لاتين :
Ghrelin is a 28 amino acid peptide which Gis secreted from the brain and the gastrointestinal system. Recent studies indicate
that ghrelin negatively affects energy balance in most mammals.
Based on its neuron distributions in hypothalamus, ghrelin coexists with many other neurons. Therefore, ghrelin controls different physiological
actions on many different tracts; one of the physiological actions is its effect on gonadotropins secretions. The present investigation was
carried out to analyze the potential involvement of ghrelin in the control of gonadotropin secretion.
Materials and Methods: Forty female Sannan goats were randomly divided into two groups; each group received daily injections of either 1
or 2 mg ghrelinJkg of body weight (BW) into the jugular vein for ten days. Blood samples were collected every 30 minutes, for two hours after
injection of ghrelin, for three days before first injection, till three days after last injection; the samples were assayed for plasma FSH and LH
concentration by the Radioimmunoassay (RIA) technique.
Results: Injections of 1 and 2 mg ghrelinJkg BW decreased the mean plasma concentration of LH throughout the injection period in all animals in the two groups. The results indicated that ghrelin significantly decreased mean plasma concentration of LH in the female Sannan goats (p<0.01); it however had no significant effect on the mean plasma concentration of FSH.
Conclusions: It was concluded that while ghrelin has no effect in the secretion of FSH, it does have an inhibitory effect on LH.
