ESSENTIAL-HYPERTENSION - COULD THE BASIC DEFECT BE IN BLOOD-SUPPLY OFVASOMOTOR CENTER

Various factors have been implicated in the pathogenesis of essential hypertension, although the exact cause of essential hypertension is st ill unknown. In this paper it is suggested that the basic pathology in essential hypertension may be an inherited defect in the blood supply of that part of reticular formation of rostral ventrolateral medulla which contains the presser area. The posited defect is one in which th e arterial branch supplying blood to the above-mentioned presser area of vasomotor center arises from an artery which is stenosed. The other branches of this stenosed artery supply adjacent areas of medullary r eticular formation concerned with other neurological functions. Due to this stenosis there is ischaemia of the presser area resulting in inc reased systemic arterial pressure. During stress, the blood requiremen t of adjacent areas of the reticular formation (whose function is stil l not clearly defined) may increase, thus further decreasing blood flo w to vasopressor area and increasing the cerebral ischaemic response. After a prolonged time, this increased blood pressure can cause hyalin e arteriolar nephrosclerosis in kidney, which may participate in the m aintenance of elevated systemic arterial pressure.