Glycoconjugates of the gastric mucosa in cold-treated chipmunks

Summary seasonal hibernation, there is reduced gastrointestinal activity, but relatively little is known of the physiology involved. In the present experimental study, male Korean chipmunks (Tamias sibiricus barberi) were maintained in cold conditions (6 °C) for 3, 5 or 9 months to mimic conditions occurring during seasonal hibernation. Changes in the composition of glycoconjugates (Gcs) of the gastric mucosa were determined after cold-treatment. Cold-treated chipmunks, in comparison with warm control animals, revealed a thinner layer of Gcs on the free surface gastric epithelium with reduced depth of their pits. Cold-treated chipmunks showed similar staining patterns and lectin affinity for Gcs as compared with warm control animals. After long-term cold treatment, reduction in the amounts of Gcs were more severe in gastric pit epithelium and glandular mucous cells than in the free surface gastric epithelium. A significant reduction in immunostaining of nitric oxide synthase (NOS) was also observed in chipmunks after long-term cold-treatment. The changes in Gcs and NOS staining patterns may be interpreted in relation with a continued but reduced functioning of the gastric mucosa throughout hibernation. However, the findings in the present experimental model for hibernation, which shows significant changes in Gcs and NOS staining patterns, need to be demonstrated during seasonal hibernation in the wild.