Mesrobian H G, Sulik K K
Department of Surgery, University of North Carolina, Chapel Hill 27599-7235.
J Urol. 1992 Aug;148(2 Pt 2):752-5. doi: 10.1016/s0022-5347(17)36711-3.
Absence or maldevelopment of the ureteral bud is thought to represent the final pathophysiological pathway resulting in renal anomalies ranging from agenesis to duplication. Little is known about the events preceding anomalous or absent ureteral bud formation. We describe the renal and ureteral anomalies found in a spontaneous murine mutation associated with a short tail: the Danforth or Sd mutation. Thirteen heterozygous pairs of mice were mated. Of 57 near-term progeny 40 had short tails. Microdissection revealed both kidneys and ureters in 35%, neither kidneys nor ureters in 27.5%, absence of the left kidney and ureter in 10%, absence of the right kidney and ureter in 7.5%, and absence of 1 or both kidneys associated with a blind-ending ureter in 20% of the mice. Scanning electron microscopy of gestational day 12 fetuses revealed unilateral or bilateral absence of the metanephros in some embryos, including some with a ureteral bud. Thus, primary absence of the metanephros may have a role in renal agenesis. Additional findings suggest that compensatory renal hypertrophy occurs in utero in the fetuses with unilateral renal agenesis. The morphological abnormalities involving the kidneys in the Sd mutation may represent an excellent model to study the pathophysiology of renal agenesis and mechanisms of normal renal development.
输尿管芽的缺失或发育不良被认为是导致从肾缺如到重复肾等一系列肾脏异常的最终病理生理途径。关于输尿管芽异常或缺失形成之前的事件知之甚少。我们描述了在一种与短尾相关的自发小鼠突变（丹福思或Sd突变）中发现的肾脏和输尿管异常。将13对杂合小鼠进行交配。在57只近足月后代中，40只尾巴短。显微解剖显示，35%的小鼠有双侧肾脏和输尿管，27.5%的小鼠既无肾脏也无输尿管，10%的小鼠左肾和左输尿管缺失，7.5%的小鼠右肾和右输尿管缺失，20%的小鼠有1个或2个肾脏缺失并伴有盲端输尿管。对妊娠第12天胎儿的扫描电子显微镜检查显示，一些胚胎存在单侧或双侧后肾缺如，包括一些有输尿管芽的胚胎。因此，后肾的原发性缺如可能在肾缺如中起作用。其他研究结果表明，单侧肾缺如的胎儿在子宫内会发生代偿性肾肥大。Sd突变中涉及肾脏的形态学异常可能是研究肾缺如病理生理学和正常肾脏发育机制的一个极佳模型。
