[The effect of prolonged treatment hypertensive rats with antihypertensive agents with different mechanisms of action on blood pressure and noradrenaline concentration in the myocardium, brain and aorta].

The authors examined the changes in arterial blood pressure and the content of noradrenaline in the myocardium, brain and aorta of rats with hypertention caused by nephrectomy, desoxycorticosterone and NaCl after a chronic six-month treatment with antihypertensive drugs. The most significant decrease of noradrenaline in the three of the examined organs was found in rats, receiving disulfiram (100 mg/kg per os). Clonidine (10 mkg/kg per os) had the strongest hypotensive effect and lowered the level of noradrenaline in the heart while it was raised in the aorta. Reserpine (10 mkg/kg subcutaneously) induced distinct reduction of NA-content in the brain, but in the other two organs--an increase. Insignificant hypotensive effect was observed in animals, receiving guanethidine (0,5 mg/kg per os), which did not affect significantly noradrenaline content in the examined organs. The increase of NA-level was found in the three of the organs of the animals, treated with alpha-methyl-DOPA (25 mg/kg per os). Furoseamide (1 mg/kg subcutaneously) induced a statisticaly significant increase of NA in the aorta and was inefficientupon the noradrenaline in the myocardium and brain.