[Glucose tolerance test and insulin secretion in patients with essential hypertension. Effect of enalapril]. / Tolerância à glicose e secreção de insulina em pacientes com hipertensão arterial essencial. Efeito do enalapril.

PURPOSE: To investigate the effects of enalapril upon glucose and insulin metabolism in patients with essential hypertension. METHODS: After 4 weeks of washout and 2 weeks of placebo therapy, 10 hypertensive patients were treated with enalapril for 12-14 weeks. Intravenous glucose tolerance test (IVGTT) during 182 minutes was performed before and after treatment. Venous blood samples were drawn for glucose and insulin determinations. RESULTS: Enalapril caused a significant fall on systolic (-19 +/- 3 mmHg) and diastolic (-10 +/- 2 mmHg) blood pressure. During IVGTT, enalapril induced a small decrease in the area under the curve of glucose (placebo 18,966 +/- 732.6 mg/dl.min and enalapril 17,575 +/- 916.1 mg/dl.min) associated with a small increase in the area under the curve of insulin (placebo 3,155 +/- 446.99 mU/ml.min and enalapril 3.577 +/- 393.92 mU/ml.min). A small rise in the disappearance rate of glucose (Kg) was also observed following enalapril (placebo 2.09 +/- 0.33 and enalapril 2.56 +/- 0.53). The insulin responsiveness to glucose increased significantly from 0.16 +/- 0.020 during placebo to 0.21 +/- 0.023 during enalapril. The insulin sensitivity remained unchanged (placebo 1.97 +/- 0.24 and enalapril 1.83 +/- 0.21). CONCLUSION: In hypertensive patients, the treatment with enalapril induced a small increase (not significant) in glucose tolerance caused by a significant rise in insulin responsiveness to glucose since no modification in insulin sensitivity was observed.

Serum uric acid in mild essential hypertension.

The mean serum level of urate and the incidence of hyperuricemia have been found to be normal in 85 patients with untreated essential arterial hypertension without renal failure. On the contrary, the incidence of hyperuricemia has been found to be high in 36 similar patients on a low salt diet and in 19 others who received diuretics. Uricemia decreased in 55 patients on a low salt diet who received hydrazinophthalazine (hydralazine) and in 10 other patients who changed their diet from a low salt diet to a diet supplying normal amounts of salt. These results indicate that essential arterial hypertension does not cause hyperuricemia.