Ciliary neurotrophic factor, a gp130 cytokine, regulates preovulatory surges of luteinizing hormone and prolactin in the rat.
Ciliary neurotropic factor (CNTF) is a neuroregulatory cytokine belonging to the interleukin-6 type cytokine superfamily. Although a few studies have reported a facilitatory action of CNTF on the reproductive axis in rodents, information along this line is still very limited. In this study, we examined a possible role of CNTF in the generation of ovarian steroid-induced luteinizing hormone (LH) and prolactin (PRL) surges in the rat, a crucial physiological event in mammalian reproduction. Experiments were performed on both normally-fed and 3-day-fasted rats, ovariectomized and primed with estradiol and progesterone. Blood was collected every 30 min between 11:00 and 18:00 h, to measure LH and PRL. Drugs were given intracerebroventricularly at 11:00 h. Compared to control serum, undiluted as well as threefold dilutions of anti-CNTF serum caused partial but significant suppression of LH surges. Both concentrations of the antibody also delayed the onset of PRL surge to a comparable degree. Fasted rats did not exhibit significant surges of the hormones, while 0.3 and 1.0 nmol, but not 0.1 nmol, recombinant human CNTF led to a dose-dependent recovery of both LH and PRL surges. These results demonstrate for the first time a significant role of CNTF in the generation of preovulatory LH and PRL surges in the rat. CNTF may thus be another humoral signal linking nutrition and reproductive function.
Watanobe
H
H
Division of Internal Medicine, Center for Clinical Research, International University of Health and Welfare, 2600-1 Kitakanemaru, Otawara, Tochigi 324-8501 Japan. watah@iuhw.ac.jp
Habu
S
S
D000818:Animals; D001921:Brain / Q000378:metabolism; D020934:Ciliary Neurotrophic Factor / Q000276:immunology / Q000494:pharmacology / Q000502:physiology*; D005260:Female; D005498:Follicular Phase / Q000502:physiology*; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007276:Injections, Intraventricular; D007986:Luteinizing Hormone / Q000378:metabolism*; D010053:Ovary / Q000378:metabolism; D011388:Prolactin / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000494:pharmacology
D020934:Ciliary Neurotrophic Factor; D007106:Immune Sera; D011994:Recombinant Proteins; D011388:Prolactin; D007986:Luteinizing Hormone