代償性肥大腎における腎内血管の形態学的検討

Abstract

The factors involved in compensatory renal hypertrophy, which usually occurs following uninephrectomy, have not been satisfactorily identified. The purpose of this experiment was to study the effect of uninephrectomy on renal hypertrophy and intrarenal arterial changes at different intervals for a period of 16 weeks in the rabbits. The microangiographic technique was used in this investigation. The medium used was 23 % barium sulfate (Micropaque) with adding 4 % gelatin. The removed kidney was washed-out with physiological saline solution with adding heparin. The medium was then injected into the renal arterial tree via the renal arterial trunk with 100 cm H20 pressure, after which it was fixed in 10 % neutral formalin for 3-5 days. The microangiography was done for this specimens. Considering the findings as a whole, the following conclusions were obtained. 1) The weight of the remaining kidney after uninephrectomy increased from 20 to 40 % in 2 to 16 weeks, with an average increase of 24.9 %. 2) The increasing rate in volume of the renal cortex was same as that of the medulla. 3) The intrarenal artery increased both in caliber and length, and the glomeruli increased in diameter. 4) The renal blood flow in the contralateral kidney, after an almost immediate sharp rise (20.2 %), settles down to about 7 %. It will be assumed that the first response of the renoprival kidney is an increase of glomerular filtration rate, possibly as a result of an early increase of renal blood flow. This would then increase the work of the tubules, which in turn would result first in cellular hypertrophy followed by hyperplasia. The intrarenal arterial changes on this experiment would give an agreement with this Dicker's suggestion.