The effect of protein-energy malnutrition on development of hypertension, glucose metabolism and insulin sensitivity in genetically hypertensive rats
Somova, L.I.; Moodley, K.
Nutrition Metabolism and Cardiovascular Diseases Nmcd 10(4): 188-194
2000
ISSN/ISBN: 0939-4753 PMID: 11079256 Document Number: 514908
The objective of the study was to elucidate the beneficial effect of protein energy malnutrition (PEM) on the development of hypertension in a genetic model of salt-sensitive hypertensive rats by evaluation of glucose metabolism and insulin sensitivity. Dahl Salt-Resistant (DSR) and Salt-Sensitive (DSS) rats were subjected to a low-protein (LP) diet (protein 5.8%, sucrose 51% and fat 7%) for 2 months. Two DSR and DSS groups on a normal protein (NP) diet and pair-fed animals served as controls. Glucose metabolism and insulin sensitivity were assessed by the euglycaemic clamp technique. The results showed that DSR rats on the LP diet displayed significantly decreased systolic blood pressure (SBP) and decreased plasma insulin and blood glucose levels with significantly increased overall peripheral glucose utilization and glucose clearance. The pair-fed DSR followed the pattern of DSR on the LP diet with decreased SBP. The most interesting SBP results were shown in the pair-fed DSS rats, which despite low food intake and body weight gain, had developed hypertension similar to DSS on the NP diet. DSS rats on the LP diet also failed to develop hypertension in contrast with the DSS rats on the NP diet and pair-fed DSS rats. DSS rats on the LP diet significantly improved their insulin sensitivity to the level of DSR rats with significantly increased glucose utilization and glucose clearance. In both DSR and DSS groups on LP and pair-fed, a significant increase of heart rate was found. This was more pronounced in the DSS groups. It is concluded that the beneficial effect of PEM on the development of hypertension is attributed to increased glucose utilization and improved insulin sensitivity.