Quantitative Changes of Cerebral Neocortical Structure in Insulin-Treated Long-Term Streptozocin-lnduced Diabetes in Rats

Johannes Jakobsen; Per Sidenius; H J G Gundersen; Ruth Østerby

doi:10.2337/diab.36.5.597

Original Contributions

Quantitative Changes of Cerebral Neocortical Structure in Insulin-Treated Long-Term Streptozocin-lnduced Diabetes in Rats

Johannes Jakobsen,
Per Sidenius,
H J G Gundersen and
Ruth Østerby

Diabetes Research Laboratory, University Institute of Pathology and Second University Clinic of Internal Medicine, Department of Neurology, Aarhus Kommunehospital Aarhus, Denmark

Address correspondence and reprint requests to Dr. J. Jakobsen, Diabetes Research Laboratory, Bartholin Bygningen, Universitetsparken, DK-8000 Aarhus C, Denmark.

Diabetes 1987 May; 36(5): 597-601. https://doi.org/10.2337/diab.36.5.597

Abstract

The brains of rats with streptozocin-induced diabetes treated with a low-dose insulin regimen (1 IU/day) were studied with morphometric techniques. After 1 yr of diabetes, brain weight decreased slightly (1350 ± 71 vs. 1521 ± 55 mg, 2P < .01) as did the volume of the neocortex (498 ± 36 vs. 567 ± 40 mm³, 2P < .05). A significant loss of neocortical neurons occurred (38 ± 2 × 106 vs. 46 ± 3 × 10⁶, 2P < .01), and the length of the capillary network in the neocortical tissue shortened disproportionately (405 ± 102 vs. 631 ± 47 m, 2P < .01), leading to increased diffusion distance. The mechanisms underlying cerebral loss in this model are unknown, but abnormalities of the vascular supply with prolongation of the route of diffusion might play a role.