dironyl and Glucose-Intolerance

Two series of experiments were performed. In the first one experiments were carried out in Koletsky genetically hypertensive lean female rats and in the normotensive female rats of Wistar strain. Glucose intolerance was induced by oligemic brain hypoxia (4 hours of occlusion of both common carotid arteries followed by 44 hours reperfusion). Brain water content were used as a marker of brain edema. Changes in insulinemia and specific insulin binding were used as expression of regulative mechanisms participating in modification of glucose tolerance. The effect of terguride (trans-dihydro-lisuride) was tested. Brain hypoxia induced glucose intolerance in both strains of rat but brain edema was found only in the normotensive females. Both abnormalities were alleviated by terguride treatment. Basal glycaemia was not changed either by the brain hypoxia or by terguride treatment, except normotensive female where brain hypoxia induced hyperglycaemia. The second series of experiments were carried out in the normotensive females. The arrangement of experiments was the same as in first series except omission of the final glucose tolerance test. Brain hypoxia causes increase in brain water content. The mentioned elevation of brain water content was alleviated by terguride treatment. Insulin binding to erythrocytes was not influenced by brain hypoxia. Terguride treatment shows decrease of insulin binding to erythrocytes. Brain hypoxia elevates insulinemia which was not alleviated by terguride treatment.

Topics: Animals; Blood Glucose; Body Water; Brain Chemistry; Brain Edema; Dopamine Agonists; Female; Glucose Intolerance; Hypoxia, Brain; Insulin; Lisuride; Rats; Rats, Inbred SHR; Rats, Wistar

Glucose tolerance, total plasma cholesterol and plasma triglycerides were studied in the genetically hypertensive obese Koletsky rats (SHR/N-cp) and in their lean siblings. The initial part of the glucose tolerance curve was substantially elevated in both obese and lean Koletsky animals compared to normotensive Wistar rats. The abnormal glucose tolerance in hypertensive rats was accompanied by increased total plasma cholesterol and plasma triglycerides. Long-term treatment with dopaminergic agonists terguride or bromocriptine (0.2 and 2.0 mg/kg/day, respectively) exerted similar effects on lipid metabolism but both drugs differed in their influence on glucose tolerance. Terguride lowered plasma lipids and normalized glucose tolerance in both obese and lean Koletsky rats. Bromocriptine reduced hyperlipidaemia but did not attenuate the abnormalities of glucose tolerance in either lean or obese Koletsky animals.

Topics: Animals; Blood Pressure; Body Weight; Bromocriptine; Disease Models, Animal; Female; Glucose Intolerance; Hyperlipidemias; Hypertension; Insulin; Lipids; Lisuride; Male; Obesity; Rats; Rats, Inbred SHR; Rats, Sprague-Dawley; Rats, Wistar; Sex Factors