title: [Daily variations of plasma enzymes, plasma albumin and liver glycogen in 8- and 28-month-old rats].
abstract: Male Sprague-Dawley rats aged 8 and 28 months (each group 36 animals) were used in our study of the variations during the day in plasma glucose, total protein and albumin, the activities of plasma ALD, LDH, GOT, GPT and the glycogen content of the liver. The variations in these enzymes shown in rats of different ages and at different times of the day were interpreted as expressions of different metabolic conditions of the liver because when changes in the membrane permeability occur or liver cells die changes in plasma enzyme activity can be expected to follow the same direction. Lowered GOT and GPT levels in the old rats and the same glycogen content of the liver as that of the young rats indicated a decreased glucose metabolism in the old animals. The LDH activity did not follow any time pattern. Daily variations in GPT and liver glycogen (the maximum of both parameters was between 4.00 and 8.00) were shown more distinctly in the old rats, whereas the daily variations in the plasma total protein and albumin showed minima between 8.00 and 12.00 in the young animals. The authors concluded that daily rhythms, essential for the function of the organism as a whole, are accentuated with ageing. On the other hand, rhythms of minor importance are desynchronized.
mesh_terms: D000375:Aging; D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D001798:Blood Proteins / Q000378:metabolism; D002940:Circadian Rhythm; D004798:Enzymes / Q000097:blood*; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008112:Liver Glycogen / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012709:Serum Albumin / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D001798:Blood Proteins; D004798:Enzymes; D008112:Liver Glycogen; D012709:Serum Albumin; D007770:L-Lactate Dehydrogenase; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase
vernacular_title: Tagesschwankungen bei Plasmaenzymen, Plasmaalbumin und Leberglykogen bei 8 und 28 Monate alten Ratten.