title: Changes in insulin sensitivity from stress during repetitive sampling in anesthetized rats.
abstract: The effect of repetitive sampling on insulin sensitivity was studied in anesthetized rats. During glucose clamp studies, glucose disposal decreased from 9.3 +/- 0.9 (SE) to 6.5 +/- 1.1 mg.kg-1.min-1 (P less than 0.05), and hepatic glucose output (HGO) increased from 1.2 +/- 0.8 to 2.4 +/- 1.1 mg.kg-1.min-1 (P less than 0.05) after a cumulative blood loss of 9 ml/kg. After a loss of 15 ml/kg, HGO rose further to 4.7 +/- 1.6 mg.kg-1.min-1 (P less than 0.05). During repetitive sampling under identical conditions, plasma adrenocorticotropic hormone (ACTH) increased, despite simultaneous saline infusion, from 68 +/- 11 to 102 +/- 15 pg/ml (P less than 0.05) with a loss of 8 ml/kg, while plasma insulin increased from 39 +/- 7 to 124 +/- 20 mU/l (P less than 0.01) with a loss of 10 ml/kg. Thereafter, ACTH and insulin rose progressively. Plasma corticosterone closely followed the pattern of the ACTH response, indicating that the stress of cumulative blood loss had a significant effect on adrenal steroid production. Increases in ACTH were retarded by reduced volume loss and accelerated by increased loss. It is concluded that stress from blood loss greater than 7 ml/kg may be a source of error in the evaluation of glucose turnover and insulin sensitivity during clamp experiments in rats.
authors.affiliation: Department of Medicine, Montefiore University Hospital, University of Pittsburgh School of Medicine, Pennsylvania 15213.
authors.forename: R H
authors.initials: RH
authors.lastname: Rao
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001800:Blood Specimen Collection / Q000379:methods*; D001810:Blood Volume; D003345:Corticosterone / Q000378:metabolism; D015309:Glucose Clamp Technique; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013312:Stress, Physiological / Q000503:physiopathology*
chemical_list: D001786:Blood Glucose; D007328:Insulin; D000324:Adrenocorticotropic Hormone; D003345:Corticosterone