The influence of delta9-tetrahydrocannabinol on pilocarpine-induced parotid secretions of the rat.

The effects of delta9-THC and its ethanol vehicle on pilocarpine-induced parotid gland secretions were investigated in rats. Single doses of delta9-THC (1, 2.5, 5 and 10 mg/kg) or 95% ethanol were administered i.v. prior to pilocarpine stimulation of saliva. Total flow, alpha-amylase and cation content of the induced saliva were determined at the end of the collection period; while heart rate and blood pressure were monitored throughout each experiment. The ethanol vehicle did not alter any of the parameters when compared to the pilocarpine controls. delta9-THC produced a bradycardia and hypotension which was not dose related in spontaneously breathing rats. Furthermore delta9-THC caused an increase in alpha-amylase concentration without a reduction in salivary flow. The results suggest that delta9-THC exerts a profound influence on the protein composition of parotid secretion which is independent of its cardiovascular effects and its ethanol vehicle.