Antihistaminic effects of total alkaloids of Aconitum kusnezoffii Reichb

The antihistaminic and antiacetylcholinic effects of the total alkaloids of Aconitum Kusnezoffii Reichb on isolated guinea pig ileum were demonstrated. Aconitine showed the same actions. Their antihistaminic potency was much weaker than that of promethazine.The contraction of guinea pig ileum induced by egg albumin could be antagonized by the total alkaloids. The hypotensive response of histamine on cats could not be antagonized by total alkaloids(iv 1-5 microg/kg). The total alkaloids lowered the blood pressure of cats. At higher doses the decrement became more significant and persistent. The ip LD50 of the total alkaloids was 98±6 microg/kg in mice and 0.14±0.05 mg/kg in guinea pigs.