title: Heat stress protects against lung injury in the neutropenic, endotoxemic rat.
abstract: The objective of this study is to determine if heat stress prior to endotoxemia diminishes cardiopulmonary dysfunction by attenuating the cytokine inflammatory response. Rats were assigned to either: 1) neutropenia; 2) heat; 3) neutropenia, LPS; or 4) heat, neutropenia, LPS. Heart rate, blood gases, and blood, lung lavage, and lung mRNA for tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and macrophage inflammatory protein (MIP)-2 were measured. Heat given before LPS resulted in a similar A-a O(2) gradient as the heat-alone and neutropenic groups (8 +/- 8 versus 8 +/- 7 versus 4 +/- 3 mm Hg) and a lower A-a O(2) gradient when compared to the neutropenic, LPS rats (8 +/- 8 versus 22 +/- 8 mm Hg, p < 0.003). Blood, lung lavage, and lung mRNA for TNF-alpha, IL-1beta, and MIP-2 were similar in the LPS rats regardless of heat. Heart rate was similar in both LPS groups but higher than non-LPS groups. Heat pretreatment attenuates lung injury in the neutropenic, endotoxemic rat but not by decreasing TNF-alpha, IL-1beta, or MIP-2 in the lung. Heat prior to LPS did not prevent cardiac dysfunction in neutropenic rats.
authors.affiliation: Departments of Pediatric Critical Care Medicine and Clinical Pharmacology, Children's Hospital of Michigan, Wayne State University, 3901 Beaubien Blvd., Detroit, Michigan, 48201-2196, USA. sheidema@med.wayne.edu
authors.forename: Sabrina M
authors.initials: SM
authors.lastname: Heidemann
authors.forename: Maria
authors.initials: M
authors.lastname: Glibetic
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D002245:Carbon Dioxide / Q000097:blood; D054426:Chemokine CXCL2; D019743:Chemokines, CXC / Q000097:blood; D003520:Cyclophosphamide / Q000494:pharmacology; D019446:Endotoxemia / Q000276:immunology*; D005334:Fever / Q000276:immunology; D006339:Heart Rate / Q000276:immunology; D018882:Heat Stress Disorders; D007375:Interleukin-1 / Q000097:blood; D008070:Lipopolysaccharides / Q000494:pharmacology; D008171:Lung Diseases / Q000517:prevention & control*; D008297:Male; D009503:Neutropenia / Q000139:chemically induced / Q000276:immunology*; D010100:Oxygen / Q000097:blood; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
chemical_list: D054426:Chemokine CXCL2; D019743:Chemokines, CXC; C513296:Cxcl2 protein, rat; D007375:Interleukin-1; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D002245:Carbon Dioxide; D003520:Cyclophosphamide; D010100:Oxygen