Further Evidence for Inhibition of Episodic Luteinizing Hormone Release in Ovariectomized Rats by Stimulation of Dopamine Receptors

摘要: Stimulation of dopamine receptors by apomorphine inhibits episodic LH release in ovariectomized rats. The present study was designed to examine further the role this process. Unrestrained, unanesthetized rats with indwelling right atrial cannulae were bled continuously (30 or 50 microliters whole blood/5 min for 3-6 h) and blood samples analyzed radioimmunoassay. Animals treated various compounds reported stimulate block receptors. ET 495, a long acting receptor stimulating agent, caused marked inhibition (2 1/2-4 h). Control injections distilled water had no effect. d-Butaclamol, blocker receptors, did not itself alter but prevented inhibitory effects seen following 495. I-butaclamol, biologically inactive form butaclamol, Measurement plasma corticosterone levels these same animals indicated increased values 495 alone (when inhibited), as well after administration d-butaclamol-pretreated change). These data support our previous hypothesis that adult rats, activation is capable inhibiting release, may play an under normal physiological conditions modulation secretion. In addition, action does appear be exerted via stress-induced adrenal corticosterone.