Comparison of tumour necrosis factor and endothelin-1 between essential and renal hypertensive patients

The present study was performed to compare circulating levels of tumour necrosis factor-alpha (TNFalpha) and plasma endothelin 1 (ET-1), of hypertensive patients with or without renal failure and with those of normotensive healthy subjects. The study population consisted of 21 healthy normotensive subjects and 22 hypertensive patients, 11 with essential hypertension, and 11 with hypertension and chronic renal failure (CRF). Plasma ET-1 levels, serum TNFalpha and creatinine, creatinine clearance, 24-h urinary albumin excretion (UAE) were assayed, and 24-h blood pressure monitoring was obtained in all subjects. Office blood pressure was similar between hypertensive patients with and without CRF. However, 24-h blood pressure was greater in patients with CRF than in those with essential hypertension and normal renal function. Patients with hypertension manifested greater ET-1 levels than normotensive subjects (P < 0.01). Serum TNFalpha and ET-1 levels were higher in hypertensive patients with CRF than in patients with essential hypertension and normotensive subjects. In the 22 hypertensive patients, TNFalpha levels were negatively correlated with serum creatinine (r=0.60; P < 0.01), and ET-1 levels were positively correlated with UAE (r=0.47, P < 0.05). The present study has shown that hypertensive patients, and particularly those with renal insufficiency, manifest abnormal blood levels of ET-1 and TNFalpha. These factors could contribute to both cardiovascular and renal damage.