Salt, Blood Pressure and Cardiovascular Changes in Human and Experimental Studies – A Review

The present review describes the effects of ingestion of high salt diet on blood pressure and attempts to elucidate some of the cardiovascular changes that give rise to elevated blood pressure. High dietary salt loading especially in experimental animals tend to result in elevated levels of arterial blood pressure. Studies in humans have also linked the high intake of salt to increase in systolic and diastolic blood pressures. Some of the pathophysiological changes include cardiac hypertrophy and enhanced cardiac contractility, enhanced contraction of blood vessels and veins in response to constrictor agonists and diminished relaxation of arterial resistance vessels to vasodilators. The combination of these factors are bound to contribute to the pressor effects of high dietary salt. In humans, there appears to be racial differences in the response to salt with blacks showing more pressor response than caucasians. The peculiar response in blacks has been attributed in part to enhanced vascular response to vasoconstrictors as well as genetic defects of the epithelial sodium channel (ENaC). More work at molecular level is required to further unwrap the genetic basis of salt hypertension especially in black populations. Key Words: Salt, Blood pressure, Blood Vessels Nigerian Medical Practitioner 46(2) 2004: 22-2