Effect of acute intravenous administration of delta-9-tetrahydrocannabinol on the episodic secretion of immunoassayable growth hormone in the rat.
Blood samples from unrestrained, unanesthetized, male rats (300-350 g) were obtained every 15 min. for 9 consecutive hrs. (1000-1900 h). Each rat received, intravenously, a vehicle injection (controls) or a 2.0 mg/kg dose of delta-9-tetrahydrocannabinol (THC) at 1300 h to determine the effect of this drug on the spontaneous episodic secretion of plasma immunoassayable rat growth hormone (rGH). Acute administration of THC suppressed the secretion of rGH, as is evident from mean plasma level (p less than .01), peak height (p less than .02), and integrated peak amplitude (p less than .02) analyses. Episodic secretion was inhibited in all animals (n = 7) receiving THC. Although further investigation is needed to define clearly the physiological mechanisms involved in this response, these data indicate that THC can inhibit the hypothalamic-pituitary control of normal episodic growth hormone secretion in the rat.
Falkenstein
B A
BA
Department of Biological Sciences, San Jose State University, CA 95192.
Holley
D C
DC
D000818:Animals; D013759:Dronabinol / Q000494:pharmacology*; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012636:Secretory Rate / Q000187:drug effects; D013997:Time Factors
D013759:Dronabinol; D013006:Growth Hormone