Neonatal PACAP administration in rats delays puberty through the influence of the LHRH neuronal system.
The onset of puberty is a concerted action of many factors which leads to cyclic LHRH release in rats. It has been demonstrated that; in common with vasoactive intestinal polypeptide (VIP), pituitary adenylate cyclase activating polypeptide (PACAP) is also involved in the differentiation of the central nervous system. In our previous work, it was shown that a single PACAP injection into neonatal female rats delayed puberty. In the present work, neonatal administration of PACAP delayed the vaginal opening and decreased the weight of anterior pituitaries, the number of expelled ova at the first ovulation and the intensity of LHRH immunostaining in the septo-preoptico-infundibular system. PACAP antiserum had a reverse effect on LHRH immunoreactivity. The other studied parameters in the latter group remained unchanged compared to control rats. It was concluded that neonatal PACAP administration delayed the onset of puberty through the influence of the LHRH neuronal system.
Szabó
F
F
Department of Human Morphology and Developmental Biology, Faculty of Medicine, Semmelweis University, Tuzolto u. 58, H-1094, Budapest, Hungary.
Horváth
J
J
Heinzlmann
A
A
Arimura
A
A
Köves
K
K
D000818:Animals; D000831:Animals, Newborn; D001835:Body Weight / Q000187:drug effects; D002490:Central Nervous System / Q000187:drug effects / Q000378:metabolism; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism*; D009479:Neuropeptides / Q000494:pharmacology*; D009929:Organ Size / Q000187:drug effects; D010053:Ovary / Q000187:drug effects; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D010903:Pituitary Gland, Anterior / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012741:Sexual Maturation / Q000187:drug effects*; D014621:Vagina / Q000187:drug effects / Q000502:physiology
C495403:Adcyap1 protein, rat; D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D007987:Gonadotropin-Releasing Hormone