Effects of tetrahydrocannabinol on rat preovulatory follicles: a quantitative cytochemical analysis

Using a microdensitometric histochemical assay, Δ5-3β-hydroxysteroid dehydrogenase activity and glucose-6-phosphate dehydrogenase Types I and II hydrogen generation were measured in preovulatory follicles from normal rats, and in follicles from rats given tetrahydrocannabinol for three days prior to sacrifice. Hydroxysteroid dehydrogenase and Type I hydrogen generation are involved in steroidogenesis, whereas Type II hydrogen generation is involved with general cellular metabolism. All ovaries were removed on pro-oestrus, frozen, sectioned and the sections reacted with the appropriate media. Enzyme activity was measured in the theca and in three regions of the membrana granulosa: peripheral antral and corona radiata. Compared to control animals, the hydroxysteroid dehydrogenase activity was significantly reduced in all follicular regions in rats exposed to tetrahydrocannabinol. Type I hydrogen generation was significantly less in the theca and peripheral region of preovulatory follicles from rats given tetrahydrocannabinol, but the same in the antral region and corona radiata. In all follicular regions examined, Type II hydrogen generation was unchanged following tetrahydrocannabinol administration. Thus, only the enzymes specifically associated with follicular steroidogenesis were affected by administration of the drug.