ストレプトゾシン糖尿病ラットのＧｌｏｍｅｒｕｌａｒ　Ｈｙｐｅｒｆｉｌｔｒａｔｉｏｎおよび尿中微量アルブミン排せつ率に対するアンギオテンシン変換酵素阻害剤の作用

Urinary microalbumin excretion rate (AER), GFR and blood pressure (BP) were examined in streptozocin (SZ) induced diabetic rats. SZ induced diabetic rats were divided in 2 groups, one untreated and the other treated, and both groups were followed for 20 weeks with a control group. Captopril, an angiotensin converting enzyme inhibitor (ACEI), was given to the treated group. In the SZ control group, AER gradually increased just after the induction of diabetes mellitus and GFR increased by 1.5 times from the 1st to 4th experimental week and returned to the former value at the 8th experimental week. With the treatment of ACEI, increments in AER and GFR were both significantly improved and BP fell significantly.<BR>We also divided the ACEI treated group into 2 groups, one was treated with ACEI in the former 10 weeks and the other in the latter 10 weeks. In the group treated during the former phase, increased AER detected in the SZ control group was significantly improved by ACEI treatment and did not increase even during the latter untreated phase. Whereas, in the group treated during the latter phase, increased AER was not improved by ACEI treatment in the latter phase. BP significantly fell with the ACEI treatment in both groups but AER did not correlate with the BP change.<BR>We conclude that both AER and GFR increase in the early stage in the SZ induced diabetic kidney and that the increment in GFR might be the initiator. ACEI is effective for treatment of the early stage of SZ induced diabetic kidney because of its hypotensive action, and also because it improves glomerular hyperfuncti on.