Increased insulin sensitivity in the high sodium one-kidney, one figure-8 hypertensive rat.
This study examines the relation between sympathetic activity and in vivo insulin-mediated glucose metabolism in a rat model of acquired hypertension. Two groups of conscious, unrestrained rats were studied in the postabsorptive state: sham-operated normotensive rats (n = 10) and renal-wrapped hypertensive rats (n = 10). Mean arterial pressure was increased in the hypertensive compared with the normotensive group in the fed (184 +/- 9 versus 144 +/- 6 mm Hg; p less than 0.01) and in the fasting (147 +/- 8 versus 112 +/- 7 mm Hg; p less than 0.01) state. After a 24-hour fast, hepatic glucose production, plasma glucose, insulin, and norepinephrine concentrations were similar in the two groups. Blood pressure did not change in either group during the 3-milliunits/kg.min euglycemic insulin clamp study; however, plasma norepinephrine concentration rose significantly in hypertensive (207 +/- 24 versus 329 +/- 11 pg/ml; p less than 0.05) but not in normotensive rats (229 +/- 23 versus 267 +/- 27 pg/ml; p = NS). During the insulin clamp study, the hepatic glucose production was similar in the hypertensive (3.8 +/- 0.8 mg/kg.min) compared with the normotensive (4.0 +/- 0.3 mg/kg.min) rats. Insulin-mediated glucose uptake was significantly higher in hypertensive than in normotensive rats (33.0 +/- 0.7 versus 25.8 +/- 0.8; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Frontoni
S
S
Department of Medicine, University of Texas Health Science Center, San Antonio.
Ohman
L
L
Haywood
J R
JR
Rossetti
L
L
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D015309:Glucose Clamp Technique; D006973:Hypertension / Q000097:blood / Q000139:chemically induced / Q000503:physiopathology*; D007328:Insulin / Q000097:blood / Q000494:pharmacology; D007333:Insulin Resistance; D008297:Male; D009638:Norepinephrine / Q000097:blood; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium
D001786:Blood Glucose; D007328:Insulin; D012964:Sodium; D009638:Norepinephrine