Central and Peripheral Chemosensitivity in Early Essential Hypertension in Man

Abstract

One of the mechanisms, not yet systematically explored in essential hypertension, is a possible enhancement of peripheral and/or central chemosensitivity of the respiratory drive. This possibility appears interesting in view of the close central interaction between the respiratory and sympathetic control systems (Koepchen et al. 1980). Significant alveolar hyperventilation and respiratory alkalosis was observed in young spontaneously hypertensive rats (SHR), and the hypothesis was proposed that the arterial chemoreflex is hyperactive in early hypertension (Przybylski 1978, 1981). Another question which might also be relevant to hypertension is whether central chemosensitivity to CO2 is increased, on account of a stimulating effect on sympathetic activity and neurogenic vascular tone (Trzebski et al. 1974, Lioy et al. 1978), which may be independent of the central respiratory drive (Trzebski and Kubin 1981).