神经型一氧化氮合酶在生后小鼠肾脏发育中的表达

EXPRESSION OF NEURONAL NITRIC OXIDE SYNTHASE IN THE POSTNATAL DEVELOPING MOUSE KIDNEY

目的观察生后小鼠肾脏发育不同阶段神经型一氧化氮合酶(nNOS)的表达,以及新生小鼠与成年小鼠肾脏nNOS表达差异,探讨nNOS在小鼠生后肾脏发育中的意义。方法分别取新生(出生小于2h)、生后3、5、7、14、40d昆明小鼠各8只,共6组。用免疫组织化学及免疫印迹方法对小鼠肾脏内nNOS表达进行定性、定量分析。结果新生小鼠生肾区nNOS呈强阳性表达,肾小管也有表达;成年小鼠肾远端小管,特别是致密斑,nNOS呈强阳性表达,集合管及肾小管均有阳性表达;新生小鼠肾脏nNOS含量最多,随后逐渐减少,成年小鼠nNOS含量最低。结论新生小鼠与成年小鼠肾脏nNOS表达部位不同,且表达含量由新生时最高到成年时降至最低。

Objective To characterize the nNOS expression during maturation in the postnatal mouse kidney, compare nNOS expression in newborn and adult mice, and discuss the role of nNOS in developing mouse kidney. Methods Kun-Ming mice were divided into 6 groups of 8 mice each： newborn and 3, 5, 7, 14 and 40 days. Intrarenal nNOS localization was detected by immunohistochemistry, and renal protein content was measured by Western blot analysis in all age groups. Results In the newborn group, nNOS was identified in the earliest stages of nephrogenesis and marked the development of this tubular segment throughout the formation of the nephron. In the adult group, nNOS was expressed in distal renal tubules, especially in the macula densa, and other renal tubules. In the newborn group, whole kidney nNOS expression was the highest, which decreased to its lowest at the adult level in the adult group. Conclusion In newborn mice, nNOS expression localization is different from that of adult mice, which is related to the physical and functional development of postnatal developing kidney. NOS expression is highest in newborn mice and decreases to its lowest level in the adults. This pattern demonstrates that nNOS may critically participate in renal function maturation during the early period of postnatal kidney development.