EN
The influence of acute (50% LD50), subacute (10% and 20% LD50) and 12-weeks (5% LD50 intoxication with carbaryl and propoxur on the adrenaline (A) and noradrenaline (NA) level in the rat adrenal glands was investigated. The level of A and NA was decreased to very low values after acute intoxication with carbaryl. Probably this effect reu sit from increase of release of accumulated acetylcholine during poisoning. With lower dosages of carbaryl and propoxur (10% and 20% LD50) different biochemical effect in adrenal glands has been observed. There was a significant decrease in the level of A and simultaneously increase in the NA level. Intoxication with 20% LD50 dose of propoxur has caused smaller alterations than the same dose of carbaryl. Carbaryl when given in a dose of 5% LD50 (12 weeks) produced within first six weeks similar changes to that which can be observed during subacute poisoning. Such character of changes (increase of NA level and decrease of A level) indicate that probably N-methylcarbamate insecticides inhibited the last step of biosynthesis of adrenaline. It can be due to inhibition of N-methyltransferase noradrenaline activity.