Okada T, Morikawa Y
Department of Veterinary Anatomy, College of Agriculture, University of Osaka Prerfecture, Japan.
Ann Anat. 1993 Feb;175(1):89-94. doi: 10.1016/s0940-9602(11)80248-7.
The development of the kidney in fetal rats was investigated morphometrically and ultrastructurally. Both the length and volume of the proximal tubule increased with age. The total volume of functional glomeruli increased markedly from fetal day 20 onward. The ratio of total glomerular volume to total proximal tubular volume decreased with age and was less than 1 from fetal day 20 onward. The cells of the proximal tubule had numerous microvilli on their free surfaces and vacuoles in the apical region of the cytoplasm after fetal day 20. These findings indicate that the relative growth of the proximal tubule has exceeded that of the glomeruli by fetal day 20, and that increased filtration induces both the growth and the differentiation of the proximal tubule during development of the fetal rat kidney.
采用形态计量学和超微结构方法研究了胎鼠肾脏的发育情况。近端小管的长度和体积均随年龄增长而增加。从胎龄20天起，功能性肾小球的总体积显著增加。肾小球总体积与近端小管总体积的比值随年龄增长而降低，从胎龄20天起小于1。胎龄20天后，近端小管细胞的游离表面有许多微绒毛，细胞质顶端区域有液泡。这些发现表明，到胎龄20天时，近端小管的相对生长已超过肾小球，并且在胎鼠肾脏发育过程中，滤过增加诱导了近端小管的生长和分化。
