Antihypertensive activity of some novel pyridinylidene arylurea derivatives in spontaneously hypertensive rats

Summary 3 novel pyridinylidene arylurea derivatives were found to lower arterial pressure in spontaneously hypertensive rats. Their relative oral potency ranged from 6 to 32 times that of guanethidine. The onset of antihypertensive action following their oral administration was less than 1 h and the duration of action ranged from 8 to over 24 h. The antihypertensive activity of the pyridinylidene arylureas was found to be associated with depletion of tissue catecholamines. Compound C depleted cardiac norepinephrine with little or no effect on total brain norepinephrine levels. It is suggested that compound C may have useful antihypertensive properties without CNS depressant activity.Acknowledgments. The authors express their gratitude to Mr L. Flataker for the preliminary behavioral studies in mice and to Dr N. Bohidar for statistical evaluation of the antihypertensive data.