兔胎儿后肾发育的组织学观察

Histological observation of metanephric kidney development in rabbit fetus

为阐明兔胎儿肾脏发育的组织学特征,采集四组比利时兔胎儿（平均体长1.9、2.75、4.7 cm和10.35 cm）肾脏,经石蜡切片,显微镜观察肾脏发育变化。结果显示：胎儿体长1.9 cm组肾脏呈果蝇卵型,在肾脏中央可见积聚的5个初级肾小体,远端小管位于其背后方,近端小管位于肾周边;胎儿体长2.75 cm组皮髓质已分化,皮质深层含第1代肾小体,皮质浅层含有分支的输尿管芽及不同发育阶段的肾小体;胎儿体长4.7 cm组皮质增厚,含第1-3代肾小体,浅层皮质类似2.75 cm组;胎儿体长10.35 cm组皮质进一步增厚,含1-7代肾小体,皮质浅层已无输尿管芽及不同发育阶段的肾小体,肾椎体和髓放线明显,肾乳头细长。这些结果表明,兔胎儿肾单位的发育是经输尿管芽的分支,从后肾中央起始向外推移,在皮质浅层大量形成肾单位,到临近出生时肾单位生成停止。

In order to clarify the histologic features of metanephric kidney development in rabbit fetus, we collected the kid-neys from four groups of Belgian hare fetus（average body length were 1.9,2.75,4.7,and 10.35 cm）and observed the histologicalchanges of kidney development with microscope. The results showed that：A Drosophila melanogaster egg form of kidney was ob-served in 1.9 cm group,the five primary renal corpuscles were collected in the centre of kidney,the distal tubules were distributedin the backside and hindside of renal corpuscles,and the proximal tubule were distributed in the outside;In 2.75 cm group,it wasalready differentiated to cortex and medulla.The first generation of renal corpuscle was observed in the deep cortex,and the branch-es of the ureteric bud and the different developmental stages of renal corpuscles were observed in superficial cortex. In 4.7 cmgroup,the 1-3 generations of renal corpuscle were observed in thick deep cortical and the superficial cortex,which is similar to2.75 cm group. In the 10.35 cm group,the 1-7 generations of renal corpuscle were observed in thickened deep cortex,but nobranches of the ureteric bud and the different developmental stages of renal corpuscle in the superficial cortical,and the renal pyra-mid and medullary ray was obvious and the renal papilla was slender.These results indicate that the nephron development of rabbitfetus is via branches of the ureteric bud, and it starts in the centre expand to outward and fordizes the nephrone at superficial cor-tex and stops generation of the nephrone when the fetus is close to the birth.