Minireview: timely ovulation: circadian regulation of the female hypothalamo-pituitary-gonadal axis.
The preovulatory surge in the secretion of LH is timed by a neuroendocrine integrative mechanism that involves ovarian estradiol levels and the endogenous circadian system. Studies in female rats and hamsters have established that the clock in the hypothalamic suprachiasmatic nucleus has a preeminent role in setting the LH surge, and anatomical, physiological, and pharmacological data are revealing the responsible connections between suprachiasmatic nucleus neurons and GnRH and estradiol-receptive areas. Recent investigations show that GnRH and pituitary cells express circadian clock genes that might play a role in the release and reception of the GnRH signal. Analysis of the circadian regulation of the LH surge may provide a model for understanding how multiple neural oscillators function within other neuroendocrine axes.
de la Iglesia
Horacio O
HO
Department of Biology, University of Washington, Box 351800, Seattle, Washington 98195-1800, USA. horaciod@u.washington.edu
Schwartz
William J
WJ
D000818:Animals; D002940:Circadian Rhythm; D006224:Cricetinae; D004703:Endocrine System / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000378:metabolism; D006066:Gonads / Q000502:physiology*; D006801:Humans; D007031:Hypothalamus / Q000378:metabolism / Q000502:physiology*; D007986:Luteinizing Hormone / Q000378:metabolism; D008954:Models, Biological; D009474:Neurons / Q000378:metabolism; D009991:Oscillometry; D010060:Ovulation; D010902:Pituitary Gland / Q000378:metabolism / Q000502:physiology*; D051381:Rats; D015398:Signal Transduction; D013493:Suprachiasmatic Nucleus / Q000378:metabolism
D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D007986:Luteinizing Hormone