The homozygous jaundiced (jj) Gunn rat exhibits hepatic microsomal enzyme activities which vary from markedly decreased to normal when compared with the non-jaundiced (JJ) Gunn rat. In order to determine if an alteration in microsomal lipid might be related to these observations, cholesterol, phospholipid, fatty acid and fluorescence polarization determinations were carried out in Gunn rats of both genotypes. Significant differences in microsomal palmitic, stearic and arachidonic acid composition were present, but these were not striking. Fluorescence polarization data best fit a two-phase linear model for both genotypes with no significant differences in breakpoint temperatures. In jj rats, the anisotrophy parameter (( r0 r) -1 -1) was significantly greater than that seen in JJ rats at both 25 and 37°C, indicating a decreased membrane fluidity in the juandiced animals. Alterations in enzyme microenvironment due to subtle changes in lipid composition may be related to the different enzyme activities observed in Gunn rats.
|Original language||English (US)|
|Number of pages||5|
|Journal||Biochimica et Biophysica Acta (BBA)/Lipids and Lipid Metabolism|
|State||Published - Feb 7 1983|
Bibliographical noteFunding Information:
We thank Dr. Milton B. Yatvin, University of Wisconsin, Department of Human Oncology, for use of his microviscosimeter and John Vorpahl and James Freimuth for technical assistance.T his research was supported by NIH grants 5 F32HD05873 and AM 21668.
- (Gunn rat liver)
- Membrane lipid