Dalterio SL, Bernard SA, Esquivel CR. Acute delta 9-tetrahydrocannabinol exposure alters Ca2+ ATPase activity in neuroendocrine and gonadal tissues in mice.
Eur J Pharmacol 1987;
137:91-100. [PMID:
3038580 DOI:
10.1016/0014-2999(87)90186-5]
[Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Acute administration of delta 9-tetrahydrocannabinol (THC) (50 mg/kg) at puberty (35-40 days) significantly (P less than 0.05) reduced Ca2+ ATPase activity in hypothalamic plasma membranes but increased, although not significantly, enzyme activity in hypothalamic tissue obtained from adult mice. In contrast, testicular Ca2+ ATPase activity was increased in pubertal THC-treated males, and significantly reduced in adults. Pituitary Ca2+ ATPase activity exhibited a dose-related decrease after acute THC administration at 0.5, 5 or 50 mg/kg, but there were no differential effects of age. Pituitary plasma membranes obtained from THC-treated males did not respond to in vitro exposure to luteinizing hormone releasing hormone (LHRH, 10(-7) M) with the marked reduction (approximately 40%) in Ca2+ ATPase activity observed in pituitaries from oil-treated controls. In addition, effects of THC appear specific for Ca2+ ATPase activity, since Mg2+ ATPase and Na+/K+ ATPase activities were not affected. These findings indicate that acute in vivo administration of THC influences Ca2+ membrane transport, in particular Ca2+ ATPase activity. These effects occur at each level of the hypothalamic-pituitary-gonadal (HPG) axis, are related to dose and developmental age at exposure, and also appear specific for Ca2+-dependent ATPase activity. Furthermore, THC exposure modulates pituitary sensitivity to LHRH receptor-mediated effects on Ca2+ ATPase activity. Therefore, effects on Ca2+ membrane transport may be involved in acute THC actions on hormonal activity at these HPG sites.
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