The purpose of this communication is to outline the results of light microscopic and immunohistological studies of the islets of male CHBB rats actively immunized repeatedly at 2-week intervals for a total of 12 times with homologous islet tissue. Of 8 animals in the group sensitized with islet antigen and complete Freund's adjuvant, 4 gave a diabetic K-value. In the group sensitized with islet antigen alone, one of 7 animals had a diabetic K-value. The pancreas of rats actively immunized with homologous islets yielded a wide variety of morphological findings in the islets and islet cells: insulitis, disorderly arrangement and pyknosis of islet cells, total replacement of some islets by a granulomatous lesion composed of infiltrating histiocytic cells, phagocytosis of particles of the nuclei of islet cells, a decrease in B cells (A/B shift) and fibrosis of the islets. On the other hand there was also proliferation and hypertrophy of islets with enlargement of the nuclei and nucleoli of islet cells, and an increase in chromatin and nuclear fission.
To evaluate the volume of the pancreas in juvenile onset diabetes (JOD), T values were measured by ultrasonography. The T value was obtained by measurement of the ventro-dorsal diameter at the body portion of the pancreas, and a good relationship was noted between the T value and volume of the pancreas in autopsy cases. Following this fundamental study, T values were measured in 52 JOD patients and 101 healthy controls. A significant correlation (p<0.01) was observed between the T value and the height in the control group. Although a good correlation was also obtained between the T value and the height in JOD, the coefficient for JOD was clearly less than that in the controls. Furthermore, a significant relationship existed between the duration of diabetes, daily injected dose of insulin and the T deviation value (= average T value of the control in the same height group-T value in the individual case of JOD). These results suggest that the growth of the pancreas in JOD did not run parallel with increase of height as compared to the control group, and the T value measured by ultrasonography appeared to represent a useful index for estimating the degree of damage of the pancreas.