title: Effects of acute and chronic counterregulatory hormone infusions on glucose tolerance and insulin sensitivity in diabetic dogs.
abstract: The effects of elevated EPI and CORT levels on KG, SI, and SG were studied in dogs with alloxan-induced diabetes. Conscious dogs received SAL, EPI 20 ng.kg-1.min-1 for 30 min (short EPI) or 72 h (long EPI), or CORT 200 micrograms.kg-1.min-1 for 60 min (short CORT) or 72 h (long CORT) before assessment of glucose metabolism by rapid sampling for glucose and insulin levels after 300 mg/kg i.v. glucose and exogenous insulin infusion designed to simulate the normal secretory pattern. With EPI infusion, KG fell acutely from 2.9 +/- 0.4 to 2.0 +/- 0.2%/min (SAL vs. short EPI, P < 0.05), but rose to 3.4 +/- 0.4%/min during long EPI. Minimal-model analysis of the glucose response with the insulin data as input showed that SI decreased acutely from 4.7 +/- 1.8 to 2.5 +/- 0.6 x 10(-5) min-1/pM (SAL vs. short EPI, P < 0.05), but rose to 4.5 +/- 2.5 x 10(-5) min-1/pM during long EPI. The effects of EPI on SG paralleled the results for KG and SI, with acute decline from 3.9 +/- 0.4 to 2.1 +/- 0.4 x 10(-2) min-1 (SAL vs. short EPI, P < 0.05) and recovery to 3.3 +/- 0.3 x 10(-2) min-1 during long EPI. During CORT infusion, KG tended to fall (SAL 2.9 +/- 0.4 vs. short CORT 2.5 +/- 0.5 vs. long CORT 2.2 +/- 0.5%/min).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: University of Melbourne, Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia.
authors.forename: M W
authors.initials: MW
authors.lastname: Sleeman
authors.forename: M J
authors.initials: MJ
authors.lastname: Christopher
authors.forename: I K
authors.initials: IK
authors.lastname: Martin
authors.forename: G M
authors.initials: GM
authors.lastname: Ward
authors.forename: F P
authors.initials: FP
authors.lastname: Alford
authors.forename: J D
authors.initials: JD
authors.lastname: Best
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000097:blood*; D004285:Dogs; D004837:Epinephrine / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005934:Glucagon / Q000097:blood; D005951:Glucose Tolerance Test; D006854:Hydrocortisone / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D007262:Infusions, Intravenous; D007328:Insulin / Q000097:blood*; D007332:Insulin Infusion Systems; D007700:Kinetics
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D005934:Glucagon; D006854:Hydrocortisone; D004837:Epinephrine