Original WBN/Kob male rats commonly develop
chronic pancreatitis by the age of 3 months, while
diabetes mellitus occurs at 9 months. In contrast, female rats of this strain do not show
pancreatitis or diabetes. The WBN/Kob-fatty rat is a homozygous (fa/fa) congenic strain for the fa allele of the
leptin receptor gene (Lepr). In WBN/Kob-fatty rats, both females and males provide a model of non-
insulin-dependent diabetes with
obesity. The
leptin receptor fatty gene (Lepr(fa)) induces
obesity and
hyperphagia. In the present study, we examined the effect of
dietary restriction on
pancreatitis and diabetes in female WBN/Kob-fatty rats. Five female fatty rats comprised a restricted feeding group with paired-feeding from 3 to 13 weeks of age, and five female lean rats comprised a control group with paired-feeding. At 13 weeks of age, two of the five female fatty rats of the control group developed
diabetes mellitus, while no female fatty rats of the restricted feeding group developed
diabetes mellitus. At this stage, pathological changes of the pancreas were observed in female fatty rats. All female fatty rats showed severe interlobular, intra-lobular and intra-islet
fibrosis. In female fatty rats of the restricted feeding group, pathological changes of the pancreas were milder those of the free-feeding fatty group. Although
dietary restriction could not completely prevent
pancreatitis in female fatty rats, the development of diabetes was inhibited by its reduction of the severity of
pancreatitis.