Mechanisms of Abnormal Renal Sodium Handling in Obesity Hypertension

Obesity-induced hypertension, like all forms of blockade or renal denervation greatly ameliorates the hypertension associated with weight gain. experimental and human hypertension studied thus far, is associated with renal dysfunctionResetting of pressure natriuresis in obesity may also be attributable to altered intrarenal forces characterized by the resetting of pressure natriuresis.In obese subjects, this resetting is caused by histologic changes in the renal medulla that may compress the loops of Henle and vasa primarily a result of increased renal tubular reabsorption as glomerular filtration rate and recta, increase tubular sodium reabsorption, and activate the renin-angiotensin system.The renal blood flow are markedly elevated.Obesity activates the sympathetic nervous and renin-quantitative importance of these intrarenal changes and their interrelationship with angiotensin systems, and causes insulin resistance and hyperinsulinemia, all of which have been neurohumoral activation in obesity is an important area for further investigation.Am postulated to increase tubular reabsorption and raise blood pressure.In humans and dogs, chronic J Hypertens 1997; 10:49S -55S 1997 American Journal of Hypertension, Ltd. hyperinsulinemia, comparable to that found in obesity, does not cause hypertension even in the KEY WORDS: Kidney, pressure natriuresis, presence of insulin resistance.Activation of the sympathetic nervous system appears to be sympathetic nervous system, renin-angiotensin system, sodium excretion.important in obesity, as chronic adrenergic E 27 kg /m 2 . 2 In some segments of the population, such as elderly African-American women, the prevalence of obesity may be as high as 70% to 80%. 3 One of the most important effects of excess weight xcess weight appears to contribute to increased blood pressure in a large proportion of essential hypertensive patients, and may be responsible for much of the increase in blood pressure that occurs in aging in industrialized gain is increased blood pressure.Population studies show that blood pressure is highly correlated to BMI countries; in populations in which weight gain does not occur with aging, there appears to be little or no in normotensive and hypertensive subjects. 1,4 -6 The importance of weight gain in causing hypertension increase in blood pressure. 1Currently, more than 30% of the adult population in the United States is mark-is reinforced by experimental studies in animals and humans showing that weight gain raises blood pres-edly overweight, with a body mass index ( BMI ) sure 7,8 and weight loss reduces blood pressure in normotensive and hypertensive subjects, even when so-