EFFECTS OF CHRONIC TREATMENT WITH DELTA-9-TETRAHYDROCANNABINOL ON UTERINE GROWTH IN THE MOUSE

The estrongenic of Delta-9-tetrahydrocannabinol (THC), the major psych oactive component of marijuana, remain unsettled. We examined the effe cts of chronic treatment of THC on uterine wet weights and nuclear H-3 -thymidine incorporation (DNA synthesis), and compared these responses with those of an acute treatment of estradiol-17 beta (E(2)) in ovari ectomized (OVX) or hypophysectomized (HYPOX) mice. As shown previously , an injection of E(2) increased uterine weights and nuclear H-3-thymi dine incorporation in epithelial cells in OVX or HYPOX mice when exami ned 18 h after the injection. Injections of THC daily for 7 days also elicited uterine weight gains and nuclear H-3-thymidine incorporation in a dose dependent manner in OVX or HYPOX mice as compared to the veh icle (oil) treated controls. Like E(2), THC induced nuclear H-3-thymid ine incorporation primarily in luminal and glandular epithelial cells. However, effects of THC in these responses were much inferior to thos e elicited by an injection of E(2). These data suggest that THC, given chronically in the mouse, behave as a weak uterotrophic agent, and TH C effects are not mediated by the pituitary.