Effect of Temperature on Isoproterenol-Induced Increases in Left Ventricular Developed Pressure

Details

• Personal Author:
  Klabunde RE ; LePorte AD ; Wilson TE
• Description:
  The goal of this project was to determine the effects of elevated cardiac temperature on preload-dependent and preload-independent regulation of left ventricular developed pressure (LVDP) in Langendorff-perfused, electrically paced (420 bpm), Sprague-Dawley rat hearts. LVDP responses to steady-state isoproterenol infusions (10-8 M) were determined at 37, 38, 39, and 40 degrees C. Preload-dependent LVDP was determined at 37 and 40 degrees C. Isoproterenol-induced LVDP and preload-dependent LVDP time controls were conducted in a separate group maintained at 37 degrees C. The percent increase in LVDP during isoproterenol infusion significantly decreased at 40 degrees C to 42+/-6 (SE), compared to 55+/-9, 55+/-6, and 53+/-7% at 37, 38, and 39 degrees C, respectively. No significant differences were observed in the percent increase in LVDP to isoproterenol among the corresponding time controls (50+/-6, 47+/-3, 56+/-4, and 56+/-5%). Preload-dependent LVDP decreased across the experimental protocol, but there were no cardiac temperature effects. These data indicate that beta-adrenergic mediated contractility is not altered by moderate heating from normothermia but is compromised at very high temperatures (40 degrees C). Cardiac temperatures from 37 to 40 degrees C do not alter the inherent preload-dependent LVDP, indicating that the Frank-Starling relation is not directly affected within this temperature range. [Description provided by NIOSH]
• Subjects:
  Animals Cardiovascular System Hot Temperature Laboratories Occupational Health Safety Temperature
• Keywords:
  Author Keywords: Heat Stress Cardiac Function Frank-Starling Relationship Heart Heat Heat Exposure Isolated Heart Laboratory Animals Langendorff Preparation Temperature Effects
• ISSN:
  0306-4565
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Ohio ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  369-373
• Volume:
  38
• Issue:
  7
• NIOSHTIC Number:
  nn:20050150
• Citation:
  J Therm Biol 2013 Oct; 38(7):369-373
• Contact Point Address:
  Thad E. Wilson, Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, Athens, OH, USA
• Email:
  thad.wilson@oucom.ohiou.edu
• Federal Fiscal Year:
  2014
• Performing Organization:
  University of Cincinnati
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Journal of Thermal Biology
• End Date:
  20260630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:b4724f96c36921fb9626295be4608a11a434aa09680d59e736f78a85724bfa1e2cb1f06063e1b6743b94751a82f0be0fdb59bc66945514a141ef5977579acd64
• Download URL:
  https://stacks.cdc.gov/view/cdc/210624/cdc_210624_DS1.pdf
• File Type:
  [PDF - 578.36 KB ]