title: In vitro evaluation of corpus luteum function of cycling and pregnant rhesus monkeys: Progesterone Production by dispersed luteal cells.
abstract: Corpus luteum function in the cycling and the pregnant rhesus monkey (Macaca mulatta) was evaluated through short term in vitro studies of progesterone production by suspensions of collagenase-dispersed luteal cells in the presence and absence of exogenous gonadotropin (human chorionic gonadotropin, HCG). Cells from mid-luteal phase of the menstrual cycle secreted progesterone, as measured by accumulation of this hormone in the incubation medium, and responded to the addition of 100 ng HCG/ml with a marked increase in progesterone secretion significantly above basal level (63.7 +/- 13.1 versus 24.7 +/- 5.5 ng progesterone/ml/5 x 10(4) cells/3 hr, X +/- S.E., n =6 ; p less than 0.05). However, luteal cells from early pregnancy (23-26 days after fertilization) secreted siginificantly less progesterone than cells of the non-fertile menstrual cycle (3.6 +/- 2.4 versus 24.7 +/- 5.5 ng/ml/5 x 10(4) cells/3 hr, n =3 ; p less than 0.05) and did not respond to HCG with enhanced secretion. By mid-pregnancy (108-118 days gestation ) luteal cells exhibited partially renewed function, and near the time of parturition (163-166 days gestation) basal and HCG-stimulated progesterone secretion (30.2 +/- 5.6 and 63.0 +/- 13.0 ng/ml/5 x 10(4) cells/3 hr, respectively; n = 3) was equivalent to that of cells from the luteal phase of the non-fertile menstrual cycle. The data suggest that following a period around the fourth week of gestation, when steroidogenic activity is markedly diminished, the corpus luteum of pregnancy progressively reacquires its functional capacity and at term exhibits gonadotropin-sensitive steroidogenesis similar to that the corpus luteum of the menstrual cycle.
mesh_terms: D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D003338:Corpus Luteum / Q000502:physiology*; D005260:Female; D000882:Haplorhini; D066298:In Vitro Techniques; D008253:Macaca mulatta; D008598:Menstruation; D011247:Pregnancy; D011374:Progesterone / Q000096:biosynthesis*
chemical_list: D006063:Chorionic Gonadotropin; D011374:Progesterone