ESTIMATION OF THE CONVULSIVE EFFECT OF CYANIDE IN RATS

Convulsions are frequently observed in severe, acute cyanide intoxicat ion. The mechanisms involved are not well known. In the present study, the convulsive effect of cyanide was examined in the rat by means of a dose threshold determination after infusion of cyanide. An optimal d ose rate of 1.80 mg/min./kg was determined. By infusing this optimal d ose rate it was possible to divide another cyanide-treated group of ra ts into two groups: one without and another with convulsions. After th e experiment all animals were killed by exposure to high intensity mic rowave irradiation. Regional dopamine, noradrenaline and main dopamine metabolites were isolated and analyzed using high pressure liquid chr omatography and electrochemical detection. Striatal noradrenaline was decreased but dopamine and its metabolites were increased in rats infu sed with cyanide at the optimal dose rate until the convulsions starte d. Animals infused with the threshold dose at the optimal dose rate di d not show any significant changes in noradrenaline or in dopamine met abolites, but all animals showing convulsions also had increased stria tal dopamine levels. Thus changes in dopamine appear to be dependent o n convulsions.