Coronary insufficiency caused by by the injection of penfamethylenetetrazol (cardiazole) injection at convulsant doses

Abstract

The injection of pentamethylentetrazol (cardiazol) at convulsant doses provokes in the rabbit an acute coronary insufficiency, relativly slight, characterized by electrocardiographic alterations and by microscopic myocardiac necroses, dispersed and precisely localized. Necroses are found constantly; electrocardiographic alterations may be lacking. Pentamethylentetrazol does not produce any decrease of the myocardium glucogene, which trouble the authors consider as characteristic of serious anoxaemias of the myocardium.

Non-convulsant doses of pentamethylentetrazol do not produce any myocardiac alterations whatever. Neither is the myocardium altered by convulsant doses whenever the production of convulsions is prevented by means of a profound anaesthesia. In superficially anaesthetized rabbits and cats, pentamethylentetrazol in intravenous injections produces convulsions and give rise to a descent of blood pressure followed by a lasting rise thereof.

The deeply anaesthetized cat shows no convulsions or hypertension after the injection. of the minimum convulsant doses of pentamethylentetrazol. Al double minimum doses this substance producess arterial hypertension and does no cause any, or only slight convulsions.

The spinal and the Sherrigton descerebrated cat suffer neither convulsions nor arterial pressure increase by the injection of pentamethylentetrazol.

The coronary insufficience produced by pentamethylentetrazol is explained by the increase of blood pressure caused by the former.