Biomaterial Database

Glucose metabolism and insulin sensitivity in Dahl hypertensive rats. 1999

L Somova, and M L Channa

Department of Human Physiology and Physiological Chemistry, University of Durban-Westville, South Africa.

There is increasing recognition that hypertension is only one facet of a metabolic syndrome that represents a cluster of risk factors including insulin resistance evident during long-term development of cardiovascular disease. The objectives of the present study were to evaluate glucose metabolism and insulin sensitivity in the Dahl genetic salt-sensitive rat model of hypertension and to find out whether there is a correlation between high blood pressure, salt sensitivity and insulin sensitivity. The experiments were performed in Wistar and Dahl salt-resistant (DSR) and salt-sensitive (DSS) rats given a normal or salt-loaded (2% NaCl in the drinking water) diet for 2 months. Glucose turnover, metabolic clearance of glucose and insulin sensitivity were determined using the euglycemic clamp technique in anesthetized animals. Four different concentrations of insulin were used (2.1, 4.2, 8.4 and 16.8 mg/kg/min) with results showing that there were no significant differences in serum glucose and insulin levels, glucose utilization and clearance and insulin sensitivity between Wistar and DSR; these groups remained normotensive throughout the 2-month experiment. However, DSS rats, even on a normal diet, developed hypertension by the end of the experiment and consistent with their hypertensive condition, significantly decreased glucose utilization and clearance and decreased insulin sensitivity were observed. The changes were more marked at higher insulin infusion rates (8.4 and 16.8 mg/kg/min). These results demonstrate that DSS rats with fully developed hypertension were insulin resistant. In contrast, DSR rats remained normotensive despite sodium loading. Sodium loading significantly exaggerated the hypertensive state of DSS rats but did not further increase insulin resistance. The results from respective weanling rats showed that even at this early stage before development of hypertension, DSS rats already had significantly increased serum insulin suggesting insulin resistance. In conclusion, the present results suggest that DSR genetically hypertensive rats were insulin resistant although insulin resistance was unrelated to high blood pressure or NaCl intake.

UI	MeSH Term	Description	Entries
D006973	Hypertension	Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.	Blood Pressure, High,Blood Pressures, High,High Blood Pressure,High Blood Pressures
D007328	Insulin	A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).	Iletin,Insulin A Chain,Insulin B Chain,Insulin, Regular,Novolin,Sodium Insulin,Soluble Insulin,Chain, Insulin B,Insulin, Sodium,Insulin, Soluble,Regular Insulin
D007333	Insulin Resistance	Diminished effectiveness of INSULIN in lowering blood sugar levels: requiring the use of 200 units or more of insulin per day to prevent HYPERGLYCEMIA or KETOSIS.	Insulin Sensitivity,Resistance, Insulin,Sensitivity, Insulin
D008297	Male		Males
D001786	Blood Glucose	Glucose in blood.	Blood Sugar,Glucose, Blood,Sugar, Blood
D004195	Disease Models, Animal	Naturally-occurring or experimentally-induced animal diseases with pathological processes analogous to human diseases.	Animal Disease Model,Animal Disease Models,Disease Model, Animal
D005260	Female		Females
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23
D015309	Glucose Clamp Technique	Maintenance of a constant blood glucose level by perfusion or infusion with glucose or insulin. It is used for the study of metabolic rates (e.g., in glucose, lipid, amino acid metabolism) at constant glucose concentration.	Euglycemic Clamping,Glucose Clamping,Euglycaemic Clamp,Euglycaemic Clamping,Euglycemic Clamp,Glucose Clamp,Glucose Clamp Technic,Clamp, Euglycaemic,Clamp, Euglycemic,Clamp, Glucose,Clamping, Euglycaemic,Clamping, Euglycemic,Clamping, Glucose,Clamps, Euglycaemic,Clamps, Euglycemic,Clamps, Glucose,Euglycaemic Clamps,Euglycemic Clamps,Glucose Clamp Technics,Glucose Clamp Techniques,Glucose Clamps,Technic, Glucose Clamp,Technics, Glucose Clamp,Technique, Glucose Clamp,Techniques, Glucose Clamp