Development of regulation of melatonin release in pineal cells in chick embryo.
Melatonin release in a pineal cell culture from 13- and 14-day-old chick embryos increased during the dark phase and decreased during the light phase of a 12 h light:12 h dark cycle. When the light-dark cycle was reversed, the pattern of melatonin release in the culture also reversed. 8-Bromo cyclic-AMP stimulated melatonin release in both the light and dark phases. However, no rhythm of melatonin release was detected under constant dark (DD) conditions in a cell culture from 14-day-old chick embryos. In 18-day-old chick embryos, the pineal cell culture expressed a circadian rhythm of melatonin release under DD conditions. These results indicate that mechanisms regulating melatonin synthesis in the avian pineal gland are established during embryonic life.
Akasaka
K
K
Department of Veterinary Physiology, Faculty of Agriculture, Miyazaki University, Japan.
Nasu
T
T
Katayama
T
T
Murakami
N
N
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D003624:Darkness; D008027:Light; D008550:Melatonin / Q000378:metabolism*; D010870:Pineal Gland / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*
D015124:8-Bromo Cyclic Adenosine Monophosphate; D008550:Melatonin