Histamine-induced release of thyrotropin releasing hormone from hypothalamic slices.
In vitro release of TRH from mediobasal hypothalamic (MBH) slices was increased in the presence of 56 mM K+ in a Ca2+-dependent manner. Addition of histamine (HA) induced a concentration-dependent release of TRH; concentrations of 3 x 10(-7) M and 10(-6) M elicited maximal and maximal stimulation respectively. Cimetidine 10(-6) M, a potent antagonist of HA H2-receptors, inhibited the effect of HA. The present results suggest that HA can trigger the release of TRH from neurosecretory nerve endings and that MBH slices are a useful preparation for studying neurohormone release.
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002927:Cimetidine / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology*; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D013973:Thyrotropin-Releasing Hormone / Q000378:metabolism*
D013973:Thyrotropin-Releasing Hormone; D002927:Cimetidine; D006632:Histamine; D011188:Potassium; D002118:Calcium