実験的先天性糖尿病ウサギ (F₁-F₄) の経過ならびに諸内分泌臓器の病理学的研究

抄録

Spontaneously diabetic rabbits were obtained in the descendants F₄ or F₅ by mating in each generation the parent animals suffering from 5- (p-Hydroxyphenylazo) -8-hydroxyquinoline or alloxan diabetes for over one month. The first spontaneously diabetic rabbits obtained in this way, were named F₁ of experimental congenital diabetic rabbit, and litters from these F₁ male and F₁ female with diabetes for over 30 days were named F₂. Repeating this procedure, F₃ and F₄ rabbits were obtained and the course of these 64 F rabbits (F₁-F₄) was observed.
Among them 36 rabbits, died or killed, were studied histologically and histometrically on the changes in their Langerhans' islets and in certain endocrine organs. The following results were obtained in contrast with 45 control rabbits.
1) The F₁, F₂, and F₃ rabbits showed better growth, and were heavier from 10 to 20% than normal rabbits. Many of them weighed over 4.5 kg in the maximum body weight. The increase in body weight is striking especially in female rabbits.
2) The blood sugar level of over 170-200 mg/dl and glucosuria for over 5 days were taken as the index for diabetic state, and the rate of occurrence of the spontaneous diabetes in F rabbits which lived 120 days, increased as generation progressed, as F₁ 44.4 %, F₂ 55.5%, F₃ 100%. The time of the first appearance of sugar in urine was shortened from generation to generation, as F₁ 135 days, F₂ 114 days, F₃ 81 days, suggesting the anticipation of diabetes.
3) The causes of death in these F₁, F₂ and F₃ rabbits were diarrhea in 10 animals, pneumonia in 5, motor paralysis of legs in 2, ileus in 1, acute cecitis in 1 and pleurisy in 1.
4) The adrenal, the pituitary and the thyroid glands of F₁, F₂ and F₃ rabbits were heavier than those of normal controls.
5) The pancreas : In non-diabetic litter rabbits, Langerhan's islets were smaller in size and the number of the β-cells was reduced. And these reduction in the number of the β-cells was remarkable especially in non-diabetic long lived litters (510-908 days). There was also the proliferation of α-cells, but there was little degenerative cellular change.
The islets in the spontaneously diabetic animals were larger than those of non-diabetic ones. And the increase in the number of the β-cells, accompanied with many hydropic degenerative cells, cells with piknotized nuclei, degranulated cells etc. was found.
In the recovered spontaneously diabetic rabbits, large, round islets due to the regenerative proliferation and hypertrophy of the β-cells were recognized. Besides them there were islets with the β-cells with hydropic degeneration or piknotic atrophic changes of nuclei and with globular dilatation of capillaries, slit formation and so no, which were found in rabbit with continued diabetes.
6) The adrenals : There was no abnormality in the width of the glomerular layer, but the fascicular layer was hypertrophied.
Histologically, no marked change was found in the glomerular layer, but in the fascicular layer there was diffuse appearance of parenchymatous cells especially in the spontarously diabetic animals.
7) The pituitary gland : All the animals showed increase in the eosinophilic cells in the pituitary gland. Especially, the pituitary of the spontaneously diabetic rabbits showed marked increase in these cells accompanied with degeneration and atrophy, but in the spontaneously recovered diabetic rabbits, these degenerative changes were slight.
8) The thyroid gland : Generally they showed the changes suggesting parenchymatous microfollicular struma.
In two non-diabetic animals,