Faculty Collaboration Database

Cytochrome P-450 omega-hydroxylase senses O2 in hamster muscle, but not cheek pouch epithelium, microcirculation. Am J Physiol 1999 Feb;276(2):H503-8

Date

02/10/1999

Pubmed ID

9950851

DOI

10.1152/ajpheart.1999.276.2.H503

Scopus ID

2-s2.0-0033036730 (requires institutional sign-in at Scopus site)   39 Citations

Abstract

The goal of this study was to investigate the role of cytochrome P-450 omega-hydroxylase in mediating O2-induced constriction of arterioles in the microcirculation of the hamster. Male Golden hamsters were anesthetized with pentobarbital sodium, and the cremaster muscle or cheek pouch was prepared for observation by intravital microscopy. Arteriolar diameters were measured during elevations of superfusate PO2 from approximately 5 to 150 mmHg. Arteriolar responses to elevated PO2 were determined in the cremaster muscle, in the retractor muscle where it inserts on the cheek pouch, and in the epithelial portion of the cheek pouch. Elevation of superfusion solution PO2 caused a vigorous constriction of arterioles in the cremaster and retractor muscles and in the epithelial portion of the cheek pouch. Superfusion with 10 microM 17-octadecynoic acid, a suicide substrate inhibitor of cytochrome P-450 omega-hydroxylase, and intravenous infusion of N-methylsulfonyl-12,12-dibromododec-11-enamide, a mechanistically different and highly selective inhibitor of cytochrome P-450 omega-hydroxylase, caused a significant reduction in the magnitude of O2-induced constriction of arterioles in the cremaster and retractor muscles. However, arteriolar constriction in response to elevated PO2 was unaffected by 17-octadecynoic acid or N-methylsulfonyl-12,12-dibromododec-11-enamide in the epithelial portion of the cheek pouch. These data confirm that there are regional differences in the mechanism of action of O2 on the microcirculation and indicate that cytochrome P-450 omega-hydroxylase senses O2 in the microcirculation of hamster skeletal muscle, but not in the cheek pouch epithelium.

Author List

Lombard JH, Kunert MP, Roman RJ, Falck JR, Harder DR, Jackson WF

MESH terms used to index this publication - Major topics in bold

Amides
Animals
Arterioles
Blood Vessels
Cheek
Cricetinae
Cytochrome P-450 CYP4A
Cytochrome P-450 Enzyme System
Enzyme Inhibitors
Fatty Acids, Unsaturated
Male
Mesocricetus
Microcirculation
Mixed Function Oxygenases
Mouth Mucosa
Muscle, Skeletal
Oxygen
Partial Pressure
Perfusion
Sulfones
Vasoconstriction