title: Plasma and hepatic cholesterol and hepatic HMG CoA reductase levels in rats fed fluid or powdered skim milk.
abstract: The effects of skim milk powder (SMP) and fluid skim milk (FSM) on plasma cholesterol (CH) and hepatic liquid concentrations, and 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG CoA) reductase activity of rats of different ages were compared. Groups of young (23 days old) and older (45 days old) rats were fed a casein -based diet and provided tap water; the casein-based diet and FSM as fluid source; or tap water and the casein diet into which SMP (25% by wt.) had been isocalorically incorporated. Plasma CH concentrations were determined at 0, 1.5, 3 and 5 wk, hepatic total lipid, triglyceride and CH at 5 wk. Half of each group were killed at wk 3 and the other half at wk 5 for determinations of HMG CoA reductase activity. Both FSM and SMP decreased plasma CH levels at 1.5 and 3 wk of feeding in the young rats; plasma CH concentrations of the older rats were not altered by either FSM or SMP. Both milk derivatives increased HMG CoA reductase activity at wk 3 and wk 5 in both ages of rat, whereas hepatic lipid levels were unchanged. In these experiments the effects of feeding FSM of SMP along with a casein-based diet were comparable and included an increase in HMB CoA reductase activity, no change in hepatic lipid levels, and a decrease in plasma CH; the latter response depended on the initial age of the rat.
mesh_terms: D000375:Aging; D000818:Animals; D001835:Body Weight; D002784:Cholesterol / Q000097:blood*; D006903:Hydroxymethylglutaryl CoA Reductases; D008055:Lipids; D008099:Liver / Q000032:analysis*; D008297:Male; D008892:Milk; D011208:Powders; D051381:Rats; D014280:Triglycerides
chemical_list: D008055:Lipids; D011208:Powders; D014280:Triglycerides; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases