Decreased membrane fluidity of erythrocytes and cultured vascular smooth muscle cells in spontaneously hypertensive rats: an electron spin resonance study.
1. Membrane fluidity of erythrocytes and cultured vascular smooth muscle cells was studied in spontaneously hypertensive rats (SHR; Okamoto and Aoki strains) by means of an electron spin resonance (e.s.r.) and a spin-label technique. 2. The values of outer hyperfine splitting (2T') and of the order parameter (S) determined from e.s.r. spectra for a fatty acid spin-label agent (5-nitroxy stearate) were significantly higher in erythrocytes of SHR (4 and 10-13 weeks of age) than in those of age-matched Wistar-Kyoto rats (WKY). This finding suggests that the membrane fluidity of erythrocytes might be decreased in SHR. 3. The fluidity of cultured vascular smooth muscle cells obtained from 10-13-week-old SHR was also reduced compared with that from WKY. 4. These results suggest that the decreased membrane fluidity might be a genetically determined abnormality of the cell membranes in SHR.
Tsuda
K
K
Department of Medicine, Wakayama Medical College, Japan.
Tsuda
S
S
Minatogawa
Y
Y
Iwahashi
H
H
Kido
R
R
Masuyama
Y
Y
D000818:Animals; D001794:Blood Pressure; D002478:Cells, Cultured; D004578:Electron Spin Resonance Spectroscopy; D004910:Erythrocyte Membrane / Q000502:physiology*; D006973:Hypertension / Q000473:pathology*; D008297:Male; D008560:Membrane Fluidity; D009131:Muscle, Smooth, Vascular / Q000473:pathology*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY