Adipocyte size distribution in fa/fa rats during development.
Epididymal fat pad adipocyte frequency distributions of obese (fa/fa) and nonobese (non-fa/fa) Zucker rats were determined from 2 to 20 wk of age. The fa/fa rats consistently displayed a higher proportion of larger adipocytes than the non-fa/fa rats of all ages studied. Increased adipocyte size preceded an increase in the number of adipocytes during the early phases of obese development. Among the fa/fa rats, the frequency of small cells continued to increase, which resulted in a bimodal distribution by 20 wk of age. Discriminant analysis suggests that the differences in adipocyte size frequency distributions at 2 wk of age may be another useful means to identify fa/fa and non-fa/fa pups prior to expression of overt obesity. Increased fat storage may reflect the lower energy expended by the very young fa/fa rats.
D000273:Adipose Tissue / Q000166:cytology*; D000375:Aging; D000818:Animals; D004195:Disease Models, Animal; D004822:Epididymis / Q000166:cytology; D005260:Female; D006720:Homozygote; D008297:Male; D009765:Obesity / Q000175:diagnosis / Q000235:genetics / Q000473:pathology*; D010641:Phenotype; D011247:Pregnancy; D051381:Rats