Experimental Studies on the Relation between the Duration of Diabetes in the Male Wistar Rat and the Disturbance of Development in Langerhans' Islet in their Offsprings

Abstract

Wistar male rats were subjected to induction of diabetes by application of alloxan and were mated with normal Wistar females to obtain their offsprings. The following three groups of the males with diabetes were used as male parents in the present report. 1) males having glycosuria for 14, 21, 22, 23, 24, 26, 27 or over 40 days. 2) males without glycosuria by insulin treatment of various length of time after over a month diabetization. 3) males with glycosuria for 23 days, during which time a period of aglycosuria for 3 days was inserted by insulin treatment at various stages. The off-springs thus obtained, weighing more than 150 gramms at the 90th day after birth, were killed and histometrical examination was done on the Langerhans' islets. The following results (1) - (5) were obtained, comparing with the similar examination of normal rats.(1) In 14 cases of normal rats (7 males, 7 females) number of cr-cells were 14.8-20.1 (17.6±1.4 in average), number of β-cells were 65.4-67.2 (66.4±0.7 in average), area of a-cells were 58.3-69.4μ2 (63.0±3.2μ2 in average), area of β-cells were 103.4-119.4μ2 (112.2±4.1μ2 in average) and area of islets were 130.6-144.3 × 100μ2 (138.0±3.6 × 100μ2 in average).(2) In 14 offsprings from the males with diabetic state of more than 40 days' duration, number of α-cells were 14.6-19.2 (17.2 ±1.6 in average), number of 8-cells were 57.8-59.4 (58.6±0.6 in average), area of a-cells were 54.2-61.3μ2 (58.2±1.8μ2 in average), area of β-cells were 105.3-111.3μ2 (108.1 ± 1.6μ2 in average) and area of islets were 114.8-132.0 x 100μ2 (125.4±5.5 x 100μ2 in average). Therefore, an evident disturbance was obserbed on the development of the β-cells.(3) Four, 7, 6, offsprings, making a total of 17, from the males whose diabetes continued for 14, 21, 22 days, respectively, did not show any disturbance in the β-cell development and they were quite identical with normal rats. On the contrary, in all cases from the males whose diabetes was continued for 27 days, the disturbance in the 8-cell development was observed in an equal degree as in the cases from the males whose diabetes continued for more than 40 days. However, the duration of illness for 23, 24 or 26 days resulted in the disturbance in 6, 5, 3 cases (total of 14) among 10, 7, 6 cases, respectively, but no disturbance was observed in the remaining 4, 2, 3 cases (total of 9), having the same histometrical pictures as normal rats.(4) The disturbance in the β-cell development was noted also in all of five offsprings from the males in which a period of aglycosuria for 3 days was inserted by insulin treatment after diabetization of a long period of time. Periods of aglycosuria for 7, 10, 14, 17, 21 or 27 days prevented the disturbance in the 8-cell development in 5, 5, 4, 5, 5 or 4 offsprings, respectively. Three groups of the offsprings 6, 3, 6 (a total of 15 rats) whose male parents had periods of aglycosuria for 4, 5, 6 days respectively were studied. It was of interest to note that some showed the disturbance in the 8-cell development and some didn't, the number of the former offsprings was 4, 1, 3 (a total of 8) and the number of the latter 2, 2, 3 (a total of 7).(5) All 12 offsprings from the males whose diabetes was maintained for 23 days, during which time having a period of aglycosuria for 3 days from the 1st or the 12th day after occurrence of diabetes, did not show any disturbance in the β-cell development. A period of aglycosuria for 3 days at the other stages of the illness was responsible for the incidence of the disturbance in the offsprings in some instances.