Corticotropin-releasing factor can stimulate gonadotropin secretion by human fetal pituitaries in superfusion.
In previous studies, corticotropin-releasing factor was found to elicit a rise in circulating adrenocorticotropic hormone in human subjects and laboratory animals, but no stimulatory effect of corticotropin-releasing factor on other pituitary hormones was detected. Since stress may be associated with luteinizing hormone changes as well as with those of corticotropin-releasing factor and adrenocorticotropic hormone, we quantified gonadotropin responses to corticotropin-releasing factor and arginine vasopressin in 11 human fetal pituitaries with use of both superfusions and static incubations. Exposure to corticotropin-releasing factor brought about a significant increase in adrenocorticotropic hormone and gonadotropin concentrations in the effluent media by means of the superfusion system. Similar concentrations of corticotropin-releasing factor significantly increased adrenocorticotropic hormone secretion into the medium by dispersed fetal pituitary cells cultured on an extracellular matrix but failed to increase luteinizing hormone and follicle-stimulating hormone secretion. Exposure to 3 mmol/l 8-bromo-cyclic adenosine monophosphate caused an increase in all three peptides, both in superfusion and static incubations. Dose-response studies showed that the effect on gonadotropin secretion occurred at concentrations of 8-bromo-cyclic adenosine monophosphate two orders of magnitude lower than those affecting adrenocorticotropic hormone secretion. The purity of corticotropin-releasing factor and arginine vasopressin used in these studies was confirmed by high-performance liquid chromatography. These in vitro results are consistent with a paracrine effect of corticotropes acting on gonadotropes. The combination of static incubation and superfusion has proved useful in elucidating the effects of different secretagogues on pituitary cells.
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D001127:Arginine Vasopressin / Q000494:pharmacology; D002478:Cells, Cultured; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology*; D004357:Drug Synergism; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D006062:Gonadotropins / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007986:Luteinizing Hormone / Q000378:metabolism; D010477:Perfusion; D010902:Pituitary Gland / Q000187:drug effects / Q000196:embryology / Q000378:metabolism*; D011189:Potassium Chloride / Q000494:pharmacology
D006062:Gonadotropins; D001127:Arginine Vasopressin; D015124:8-Bromo Cyclic Adenosine Monophosphate; D011189:Potassium Chloride; D000324:Adrenocorticotropic Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D003346:Corticotropin-Releasing Hormone