Abstract
Supersensitivity to catecholamines in various organs after reserpine treatment has been reported by many investigators. Trendelenburg et al. (1) described that this action was associated with the impairment of uptake of catecholamines to adrenergic nerve terminals. On the other hand isoproterenol, one of the catecholamines, was not retained by the heart (2). Neither cocaine (3) nor denervation (4) could cause supersensitivity to this amine.
However, Fleming et al. (5) reported that after reserpine treatment the isolated ileum of rabbit became more sensitive to isoproterenol and recently Khan et al. (6) also showed that on the isolated rat fundus strip preparation reserpine and guanethidine increased the sensitivity to isoproterenol. But further evidences for these phenomena were not obtained.
In a previous paper (7) authors reported briefly that on the blood pressure of the rat treated with reserpine the hypotensive action of isoproterenol was potentiated. In order to confirm our previous results, the effects of reserpine on the sensitivity to isoproterenol and a new adrenergic β-stimulating agent trimethoquinol (8) were studied on the blood pressure of the rat.
