Heat-induced increases in endothelial NO synthase expression and activity and endothelial NO release.

Abstract

Endothelial nitric oxide (NO) synthase (eNOS) is regulated by heat shock protein 90 (HSP90), a heat-inducible protein; however, the effect of heat shock on eNOS expression and eNO release is unknown. Bovine aortic endothelial cells were incubated for 1 h at 37 degrees C, 42 degrees C, or 45 degrees C and cell lysates were evaluated with the use of Western blotting. We observed a 2.1 +/- 0.1-fold increase in eNOS protein content, but no change in HSP90 content, HSP70 content, or HSP90/eNOS association, 24 h after heat shock at 42 degrees C. We also observed a 7.7 +/- 1.5-fold increase in HSP70 protein content, but did not observe a change in eNOS or HSP90 24 h after heat shock at 45 degrees C. eNOS activity and maximal bradykinin-stimulated NO release was significantly increased 24 h after heat shock at 42 degrees C. Heat shock in rats (core temperature: 42 degrees C, 15 min) resulted in a significant increase in aortic eNOS, HSP90, and HSP70 protein content. The aorta from heat-shocked rats exhibited a decreased maximal contractile response to phenylephrine, which was abolished by preincubation with NG-nitro-l-arginine. We conclude that prior heat shock is a physical stimulus of increased eNOS expression and is associated with an increase in eNOS activity, agonist-stimulated NO release, and a decreased vasoconstrictor response.

• Authors: M Brennan Harris, Michele A Blackstone, Hong Ju, Virginia J Venema, Richard C Venema
• Journal: American journal of physiology. Heart and circulatory physiology (Am J Physiol Heart Circ Physiol) Vol. 285 Issue 1 Pg. H333-40 (Jul 2003) ISSN: 0363-6135 [Print] United States
• PMID: 12663266 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Coloring Agents
• HSP70 Heat-Shock Proteins
• HSP90 Heat-Shock Proteins
• Vasoconstrictor Agents
• Phenylephrine
• Nitric Oxide
• Nitric Oxide Synthase
• Nitric Oxide Synthase Type III
• Nos3 protein, rat
• Trypan Blue

Topics

• Animals
• Cattle
• Cell Survival (physiology)
• Cells, Cultured
• Coloring Agents
• Endothelium, Vascular (enzymology, metabolism, physiology)
• Gene Expression Regulation, Enzymologic (physiology)
• HSP70 Heat-Shock Proteins (biosynthesis)
• HSP90 Heat-Shock Proteins (biosynthesis)
• Heat-Shock Response (physiology)
• Immunoblotting
• In Vitro Techniques
• Male
• Muscle Contraction (drug effects)
• Muscle, Smooth, Vascular (physiopathology)
• Nitric Oxide (metabolism)
• Nitric Oxide Synthase (biosynthesis, metabolism)
• Nitric Oxide Synthase Type III
• Phenylephrine (pharmacology)
• Precipitin Tests
• Rats
• Rats, Sprague-Dawley
• Trypan Blue
• Vasoconstrictor Agents (pharmacology)