PURPOSE--To evaluate the effects of captopril (Cpt).on carbohydrate metabolism and growth hormone (GH) in adults hypertensive obese patients with normal (NGT) or impaired (IGT) glucose tolerance and left ventricular hypertrophy. METHODS--Ten patients (53 +/- 8 years), 8 women and 2 men, white, body mass index (BMI) > or = 26kg/m2, left ventricular mass index (LVMI) > 135g/m2 in man and > 110g/m2 in woman, with diastolic blood pressure (DBP) 95-115mmHg after 3 weeks of placebo, were identified by oral glucose tolerance test (OGTT-75g) as either with NGT or IGT, and treated with Cpt 25mg t.i.d. for 8 weeks. At the 8 weeks, dosage was increased to 50mg b.i.d. if DBP > 90mmHg or the decrease of the DBP < 10, during the next 8 weeks. OGTT and clonidine tests (0,04mg/kg) with determinations, every 30 minutes of glucose, insulin, and GH during 2 hours, were performed. RESULTS--Cpt lowered SBP and DBP in the NGT group and IGT group. The LVMI and the left ventricular mass (LVM) decreased in the IGT group with no significant change in the NGT group. Cpt promoted in the IGT group decrease in the area under the curve (AUC) of glucose, and AUC of insulin, with increase of the AUC of the percent of the beta cell function, AUC of HC, and insulin sensitivity index with no significantly change in the NGT group. CONCLUSION--Adults hypertensive obese patients with IGT had decreased significantly in mean fasting level of GH concentrations compared to age, race, and BMI matched hypertensive patients with NGT. Treatment with Cpt induced a significant increased of the GH, with improvement of the metabolism in patients with IGT.