General pharmacology of cicletanine.
Cicletanine is a new antihypertensive molecule which acts directly on vascular smooth muscle by increasing prostacyclin synthesis and interacting with various agents which mobilize intracellular Ca2+ ions. General pharmacological studies have shown that in the anaesthetized normotensive dog, cicletanine does not induce tachycardia (even at high doses) and does not modify aortic, femoral or coronary blood flow. Moreover, cicletanine shows a protective effect on vascular permeability and capillary hyperpermeability. This protective action on the vascular wall is of importance, since one of the direct vascular consequences of arterial hypertension is a fragilisation of vessel walls, tissue oedema and even vascular rupture. Cicletanine slows down the thrombogenic process initiated by electric arterial stimulation. Retardation of the thrombogenic process by the drug may be explained by the stimulation that cicletanine exerts on the synthesis and production of prostacyclin. Behavioural studies in mice, rats and primates have shown that cicletanine has no sedative effects, even at very high doses. General pharmacological studies have demonstrated that both cardiovascular function and the central nervous system are equally tolerant to cicletanine. Cicletanine is an antihypertensive agent which has no effect on cardiovascular haemodynamics and is able to prevent some rheological and vascular-linked cardiac risks of hypertension.