... collateral resistance by an average of 135%. Glyceryl trinitrate (0.5 mg sublingually) reduced collateral resistance by an average of 45%. Hydrallazine and isoprenaline had an inconsistent dilator effect; the direct action of these drugs may have been offset by the reduction in distending pressure which...

...C. Chevillard; B. Saiag; M. Worcel 1. Hydrallazine relaxes the rat tail artery by a direct action on vascular smooth muscle cells, which appears to be modulated by the action of sympathetic nerve terminals. 2. There is a gradient of response to hydrallazine in arteries from normotensive Wistar rats...

... anti-hypertensive effect. 2. Treatment was begun at 12 weeks of age in groups of eleven to seventeen rats with one of the following drugs: reserpine, chlorothiazide or hydrallazine. Blood pressures were recorded by the tail method under light ether anaesthesia every 2 weeks until the rats were...

... with moderate hypertension control with minoxidil was achieved earlier and more easily than with hydrallazine. 4. Three patients developed secondary resistance and required addition of guanethidine or increased doses of diuretics. 5. Fluid retention and hypertrichosis were the main side effects with minoxidil...

...G. Connor; R. L. Wilburn; C. M. Bennett 1. Thirty moderately severely hypertensive patients were studied in a double-blind comparison of minoxidil and hydrallazine in combination with frusemide and propranolol. 2. Blood pressure control in both groups of patients was satisfactory but long-term...

...Priscilla Kincaid-Smith; A. S. P. Hua; J. B. Myers; Ileene Macdonald; P. Fang 1. Two vasodilators, prazosin and hydrallazine, have been compared in three double-blind cross-over studies designed to test their effect when used in combination with a β-adrenoceptor-blocking agent and a thiazide. 2...

...K. Rasmussen; H. Æ. Jensen 1. In a cross-over study between hydrallazine and prazosin in fifteen patients, also treated with the β-receptor-blocking agent propranolol, 1 mg of prazosin was found to be equipotent with 30 mg of hydrallazine. 2. All patients were known to tolerate hydrallazine. In one...