title: Alteration of delta 9-tetrahydrocannabinol-induced teratogenicity by stimulation and inhibition of its metabolism.
abstract: Treatment of pregnant mice with delta 9-tetrahydrocannabinol (THC) significantly increased the incidence of in utero deaths. SKF-525A pretreatment increased the incidence of THC-induced in utero deaths. THC also significantly reduced the body weight of surviving fetuses. Phenobarbital treatment antagonized THC-induced reduction of fetal body weight, but did not reduce resorption rate. Administration of THC, 50 or 200 mg/kg, did not induce fetal anomalies. However, both SKF-525A and phenobarbital treatment potentiated THC-induced cleft palates. SKF-525A treatment plus THC produced 36% cleft palates. Phenobarbital treatment plus THC produced 77% cleft palates. Pretreatments altered the level of tetrahydrocannabinol plus metabolites found in plasma, placenta, fetus and amnionic fluid. In general, SKF-525A increased levels and phenobarbital decreased levels. Two chemically reactive metabolites of THC are proposed, 9,10-epoxyhexahydrocannabinol and an 11-oxo derivative. SKF-525A pretreatment increased the concentration of both of these metabolites. Phenobarbital treatment increased the levels of the proposed 9,10-epoxyhexahydrocannabinol. Possible covalent binding of THC was observed. An active metabolite theory may apply to the teratogenic properties of THC.
mesh_terms: D000653:Amniotic Fluid / Q000378:metabolism; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002972:Cleft Palate / Q000139:chemically induced; D013759:Dronabinol / Q000097:blood / Q000378:metabolism / Q000494:pharmacology*; D004347:Drug Interactions; D005260:Female; D005313:Fetal Death / Q000139:chemically induced; D005333:Fetus / Q000187:drug effects / Q000378:metabolism; D005865:Gestational Age; D008431:Maternal-Fetal Exchange; D051379:Mice; D010634:Phenobarbital / Q000494:pharmacology; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D011335:Proadifen / Q000494:pharmacology; D013723:Teratogens / Q000378:metabolism*
chemical_list: D013723:Teratogens; D013759:Dronabinol; D011335:Proadifen; D010634:Phenobarbital