Nutritional status modifies insulin-mediated glucose uptake in spontaneously hypertensive rats.
In this study we quantified insulin-mediated glucose uptake in weight-matched (260-330 g) fed (6-8 h fast) and fasted (24 h fast) male rats with spontaneous hypertension (SHR) and control Wistar-Kyoto (WKY) rats. To accomplish this goal, rats were infused continuously for 165 min with glucose and insulin. Blood was taken at frequent intervals from 120-165 min, and the values averaged to determine the steady-state plasma glucose (SSPG) and insulin (SSPI) concentrations. In some studies epinephrine and propranolol were added to the infusate in order to suppress endogenous insulin secretion. Steady-state plasma insulin (SSPI) concentrations were similar in SHR and WKY during the three infusion studies (382-483 pmol/L). However, SSPG was significantly higher in fed SHR as compared to fed WKY during infusions performed with (9.4 +/- 0.8 vs 7.0 +/- 0.4 mmol/L, p < 0.05) or without (8.6 +/- 0.2 vs 7.0 +/- 0.6 mmol/L, p < 0.05) epinephrine and propranolol in the infusate. In contrast, SSPG concentrations (mmol/L) were similar in SHR (6.8 +/- 0.3) and WKY rats (6.5 +/- 0.6) when they were studied after a 24 h fast. These results demonstrates that differences in insulin-mediated glucose removal from plasma between SHR and WKY rats will vary as a function of nutritional status.
Plato
P A
PA
Department of Medicine, Stanford University School of Medicine, California.
Mondon
C E
CE
Reaven
G M
GM
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D004435:Eating / Q000502:physiology*; D004837:Epinephrine / Q000494:pharmacology; D005215:Fasting / Q000097:blood*; D005947:Glucose / Q000493:pharmacokinetics*; D006973:Hypertension / Q000235:genetics / Q000503:physiopathology*; D007328:Insulin / Q000097:blood / Q000378:metabolism / Q000494:pharmacology*; D000078790:Insulin Secretion; D008297:Male; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR / Q000502:physiology*; D011921:Rats, Inbred WKY; D013997:Time Factors
D001786:Blood Glucose; D007328:Insulin; D011433:Propranolol; D005947:Glucose; D004837:Epinephrine