title: Effect of hyperglycemia and nitric oxide synthase inhibition on heat tolerance and induction of heat shock protein 72 kDa in vivo.
abstract: Diabetes and nitric oxide synthase (NOS) inhibition both exacerbate mesenteric ischemia/ reperfusion injury. Heat shock protein 72 (HSP-72) protects against KDa ischemia/reperfusion damage in vivo. The effect of diabetes on HSP-72 expression in vivo is unknown. The aim of this study was to determine the effects of diabetes and NOS inhibition on HSP-72 induction in vivo. Rats were assigned to four groups: control (C), streptozotocin-induced diabetic (D), acute hyperglycemia (A), and L-N(omega)-nitro-L-arginine treated (L). Rats were subjected to hyperthermia and allowed to recover for 4 hours. Intestine and liver samples from heated (H) and nonheated (NH) rats were analyzed for HSP-72 by Western blot. HSP-72 levels were increased significantly in CH compared to CNH rats. No deaths occurred in CH rats; however, death rates were significant in AH, DH, and LH rats. DH rats died earlier than LH and AH rats. HSP-72 in liver and intestine was reduced significantly in LH rats. When compared with CH rats the surviving AH and DH rats exhibited similar HSP-72 levels in the liver. Diabetes, acute hyperglycemia, and L-N(omega)-nitro-L-arginine treatment lower heat stress tolerance. NOS is required for HSP-72 expression, but not survival. Diabetics who survive heat stress moderately express HSP-72. Characterization of altered thermotolerance and HSP-72 may provide mechanisms for the deranged diabetic stress response.
authors.affiliation: Department of Surgery, Walter Reed Army Medical Center, Washington, DC, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Swiecki
authors.forename: Alexander
authors.initials: A
authors.lastname: Stojadinovic
authors.forename: Jimie
authors.initials: J
authors.lastname: Anderson
authors.forename: Aiping
authors.initials: A
authors.lastname: Zhao
authors.forename: Harry
authors.initials: H
authors.lastname: Dawson
authors.forename: Terez
authors.initials: T
authors.lastname: Shea-Donohue
mesh_terms: D000208:Acute Disease; D000818:Animals; D015153:Blotting, Western; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism* / Q000503:physiopathology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000096:biosynthesis*; D006358:Hot Temperature; D006943:Hyperglycemia / Q000378:metabolism* / Q000503:physiopathology; D007413:Intestinal Mucosa / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000502:physiology*; D019335:Nitroarginine / Q000494:pharmacology; D018384:Oxidative Stress; D051381:Rats; D017207:Rats, Sprague-Dawley; D013312:Stress, Physiological / Q000209:etiology / Q000378:metabolism*
chemical_list: D004791:Enzyme Inhibitors; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D019335:Nitroarginine; D019001:Nitric Oxide Synthase