A single dose (38-nmol) of human 26RFamide (26RFa; another member of RFamide superfamily) was also tested.
Likewise, 26RFa administration also significantly decreased (P less than 0.05) plasma T concentration.
Keywords: Hypothalamus-pituitary-gonadal axis, kisspeptin-10, 26RFa, plasma testosterone, chicken.
26RFamide (26RFa) peptide, another member of the RFamide superfamily of peptides, originally isolated in frog, has also been cloned in various mammals (Chartrel et al., 2003).
Although recently, a functional KP-Kiss1r system has been unveiled in fish (Kanda et al., 2008; van Aerle et al., 2008), but currently, to thebest of our knowledge, no data are available for the role of KP and 26RFa in the avian reproductive physiology.
Human 26RFa (TSGPLGNLAEELNGYSRKKGGFSFRF- NH2) was synthesized in the lab of one of the authors (Dr.
The experimental design of this study consisted of blood samplings before and after KP10, 26RFa, vehicle (normal saline), and hCG intravenous (i.v.) treatments.
A single dose of 26RFa (38-nmol) was administered to a group of four birds.
The doses of KP10 and 26RFa were selected from the neuroendocrine effective doses of these peptides in monkeys.
Recently, two new members of the RFamide superfamily of peptides, KP and 26RFa have been identified (Chartrel et al., 2003,2006; Kotani et al., 2001).
In the present study, therefore, we have studied the effect of peripheral administration of human KP10 and human 26RFa on the plasma T levels in the adult male broiler breeder birds.