Hypertension which is part of the metabolic syndrome has frequently a family background. The authors investigated therefore indicators of insulin sensitivity by the method of a hyperinsulinaemic euglycaemic clamp in the offspring of hypertensive probands. In conjunction with the increased interest in the role of muscles in influencing insulin sensitivity the authors were also interested in serum amino acid levels. They examined a group of 15 healthy offspring of hypertonic subjects (PHT) and compared them with a group of 18 healthy volunteers without a family-history of hypertension. PHT had as compared with controls a higher systolic pressure (117 +/- 7.2 mm Hg vs. 106.1 +/- 11.7 mm Hg p < 0.01). In the clamp examination in PHT significantly lower indexes of tissue insulin sensitivity were recorded, SI (46.51 +/- 11.8% vs. 54.3 +/- 7.79%, p = 0.02) and ISI (6.6 +/- 3.99 vs. 9.88 +/- 5.05, p < 0.01). In the PHT group were, in addition to the different ratio of some branched chain amino acids and tyrosine, also relations between indicators of insulin sensitivity and arginine. It is thus obvious that signs of reduced insulin sensitivity are present in PHT already in the preclinical stage. Relations between the altered insulin sensitivity and arginine, the precursor of nitrogen oxide, apparent only in PHT could be a stimulus for seeking associations with endothelial damage described in insulin resistant conditions.

Keywords: Adult; Amino Acids /blood/; Glucose Clamp Technique; Humans; Hypertension /genetics/; Insulin Resistance; Male