CARDIOVASCULAR EFFECTS OF Δ9‐TETRAHYDROCANNABINOL IN CONSCIOUS AND ANAESTHETIZED DOGS

Abstract

1 Temporal effects of Δ⁹-tetrahydrocannabinol (THC) on heart rate and blood pressure in conscious dogs were compared to those in anaesthetized dogs. 3 In conscious dogs, THC in doses of 0.25 and 0.1 mg/kg resulted in maximal heart rate reductions of 48 and 41%, respectively, and in no significant change in blood pressure. 3 In anaesthetized animals THC in doses of 0.5 and 0.25 mg/kg caused a peak reduction in heart rate of 38 and 34%, and of blood pressure of 24 and 8%, respectively. 4 The results demonstrate that the bradycardia in response to THC in dogs is independent of the concomitant anaesthesia. 5 We conclude that the discrepancy between heart rate response to THC in dogs and in man is due to a species difference.