Naphthol-yellow-S protein content of individual rat hepatocytes as related to food intake and short-term starvation.
With regard to the protein content, as analysed cytophotometrically, of hepatocytes from rats kept under a 12L 12D photoperiod (photophase 7:00-19:00), the following facts have been established: 1) Hepatocytes of different classes of ploidy all demonstrate, more or less equally, daily variations in protein content and also its reduction after 24-h fasting. 2) With computer analysis of data obtained at eight time points during a period of 24 h, a sinusoidal curve of the protein content of individual mononuclear tetraploid hepatocytes throughout the day could be demonstrated with a maximum at 6:20 and a minimum at 18:20. 3) Animals, fed with meals via a dispensing machine from 23:00 to 24:00 only, show a similar sinusoidal curve but with higher amplitude, and a virtually identical mean value as those fed ad libitum. The maximum was found at 10:40, revealing a time lag of 12 h after food intake, the minimum at 22:40. 4) Trained animals deprived of food during the standardized feeding time revealed a moderate reduction of their hepatocyte protein content in the first 6 h, then a 6-h period with a steep fall followed by a slower reduction. After 24 h, the mean hepatocyte protein mass had decreased to 72% of that at the commencement of fasting at 23:00.
D000818:Animals; D002940:Circadian Rhythm; D003201:Computers; D003592:Cytophotometry; D005502:Food; D006003:Glycogen / Q000378:metabolism; D008099:Liver / Q000032:analysis / Q000166:cytology / Q000378:metabolism*; D008297:Male; D009282:Naphthalenesulfonates; D011003:Ploidies; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013217:Starvation / Q000378:metabolism*; D013997:Time Factors
D009282:Naphthalenesulfonates; D011506:Proteins; C018589:lysosomal proteins; C009824:naphthol yellow; D006003:Glycogen