R Takaki — Page 6 | PubMed Health

PubMedDate not supplied

Loss of sulfated carbohydrate from the glomerular podocyte as a cause of albuminuria in experimental diabetic rats: ultrastructural histochemical study.

Decrease of anionic sites and heparan sulfate proteoglycan has been demonstrated in diabetic glomerular basement membrane (GBM) and causally related to albuminuria. The HID-TCH-SP-PD technique is a sensitive histochemical method for negatively charged sulfated carbohydrates. In this study, we examined the localization of HID-TCH-SP-PD reaction in the glomeruli of diabetic and control rats. In both rats, the reaction was found in association with the surface of podocytes and with GBM. In diabetic rats, the former-associated reaction was markedly reduced. By contrast, the latter-associated reaction did not show any differences between both animal groups. Urinary albumin excretion (UAE) increased significantly in alloxanized rats. It is suggested that a decrease of podocyte-associated sulfated carbohydrates, the primary observed change, gives rise to albuminuria in alloxan diabetic rats.

Albuminuria↗

PubMedDate not supplied

Microencapsulation of pancreatic islets. A technique and its application to culture and transplantation.

Hamster pancreatic islets were encapsulated by a biocompatible membrane composed of the molecular sequence of alginate-polylysine-alginate. The encapsulated islets released insulin into the culture medium in response to secretagogues in short-term incubation. In long-term culture, the encapsulated islets maintained their insulin-releasing capacity for 28 days at a level similar to that of the unencapsulated islets. No overgrowth of fibroblastic cells was observed inside the capsule even after 70 days of culture. Further, the encapsulated hamster islets were xenotransplanted to streptozotocin-induced diabetic rats intraperitoneally. Some of the encapsulated islets, which were recovered from a recipient 27 days after transplantation, were found to be viable, although prolonged normalization of fasting plasma glucose levels of the recipients could not been achieved. On the contrary, the unencapsulated islets were replaced by massive connective tissue elements and insulin-positive B cells were hardly detected within the grafts 22 days after transplantation. The results of this study seem to confirm the potential of the application of the encapsulating technique to primary culture of parenchymal cells and to transplantation of pancreatic islets.

Alginates↗