Early hyperplastic renal growth after uninephrectomy in adult female rats.
Early hyperplastic renal growth after uninephrectomy in adult female rats.
复制标题
成年雌性大鼠单肾切除术后早期增生性肾脏生长。
作者：
S. Mulroney;C. Pesce
在幼年和成年雄性大鼠中，单肾切除(UNX)后早期加速的残肾生长通过交替的机制发生，这可能控制了UNX后发生的肾脏生长的类型。成年雄性大鼠早期肾脏代偿性生长(CRG)是生长激素依赖性的，但与肾脏胰岛素样生长因子I(IGF-I)系统的变化无关。相比之下，CRG在幼年雄性大鼠中不依赖生长激素，但与肾脏IGF-I系统的显著增加和肾脏的增生性生长有关。少数对雌性动物早期CRG进行研究的研究表明，残留肾脏的生长速度慢于雄性动物，而且存在增生成分，表明潜在的性别差异。目前尚不清楚这些差异是否源于不同的增长机制。本研究的目的是确定UNX后成年雌性大鼠早期残肾生长的速度、类型和可能的机制。测定清醒、假手术和UNX成年雌性Wistar大鼠术后24小时的GH水平。与先前在成年雄性UNX大鼠中的发现不同，UNX雌性大鼠的搏动性生长激素水平并未升高。用生长激素释放因子拮抗剂抑制GH释放时，残余肾生长与生理盐水/UNX组无明显差异(分别为25.7±4.8%和27.7±2.1%)。这种生长激素非依赖性CRG与成年和青少年女性残肾的显著增生性生长有关，通过溴脱氧尿嘧啶核苷掺入和总DNA增加来确定。与成年女性的有丝分裂生长相关的还有残余肾脏IGF-I受体基因表达显著增加2-4倍，这发生在存在和不存在脉动性GH分泌的情况下。成年女性残肾早期生长率与男性无明显差异(24 h分别为0.21±0.02和0.20±0.02 g，48 h分别为0.26±0.02和0.30±0.03 g，P=NS)。因此，在雌性大鼠中，CRG的初始阶段不依赖于GH，但与残余肾脏IGF-I受体基因表达的显著增加和肾脏的增生性生长有关。这除了先前的发现之外，还表明UNX后早期CRG存在性别差异。此外，研究结果证实，CRG初期的机制似乎是显著的增生性残肾生长的关键决定因素。
The early, accelerated remnant kidney growth following uninephrectomy (UNX) occurs through alternate mechanisms in juvenile and adult male rats, which may govern the type of renal growth that occurs after UNX. Early compensatory renal growth (CRG) in the adult male rat is GH dependent, but independent of changes in the renal insulin-like growth factor I (IGF-I) system. In contrast, CRG is GH independent in the juvenile male rat, but is associated with significant increases in the renal IGF-I system, and hyperplastic kidney growth. The few studies that examined early CRG in female animals suggest that remnant kidney growth is less than that observed in males, and there is a hyperplastic component, indicating potential gender differences. Whether these differences result from alternate growth mechanisms is unknown. The purpose ofthe present study was to determine the rate, type, and potential mechanism of early remnant kidney growth in adult female rats after UNX. GH levels were determined in conscious, sham-operated, and UNX adult female Wistar rats 24 h postsurgery. Unlike previous findings in adult male UNX rats, pulsatile GH levels were not elevated in UNX female rats. When GH release was suppressed using an antagonist to GH-releasing factor, remnant kidney growth was not different from that in saline/UNX remnant kidneys (25.7+/-4.8% vs. 27.7+/-2.1%, respectively, at 48 h post-UNX). This GH-independent CRG was associated with significant hyperplastic growth in both adult andjuvenile female remnant kidneys, as determined by bromodeoxyuridine incorporation and increases in total DNA. Also associated with the mitogenic growth in the adult female were significant 2- to 4-fold increases in remnant kidney IGF-I receptor gene expression, which occurred in the presence and absence of pulsatile GH secretion. Lastly, the growth rate of adult female remnant kidneys was not different from that observed in male remnant kidneys at these early time points (0.21+/-0.02 vs. 0.20+/-0.02 g at 24 h, and 0.26+/-0.02 vs. 0.30+/-0.03 g at 48 h in female and male remnant kidneys, respectively; P = NS). Thus, in female rats, the initial phase of CRG is GH independent, but is associated with significant increases in remnant kidney IGF-I receptor gene expression and hyperplastic renal growth. This, in addition to previous findings, indicates that there are sex differences in early CRG after UNX. Moreover, the findings confirm that the mechanism governing the initial phase of CRG appears to be a critical determinant for significant hyperplastic remnant kidney growth.
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影响因子：
13.2
作者：
BAYLIS, C;WILSON, CB
通讯作者：
WILSON, CB
生长激素直接刺激犬肾近曲小管的糖异生。
DOI：
10.1152/ajpendo.1989.257.5.e751
发表时间：
1989
期刊：
The American journal of physiology
影响因子：
--
作者：
Rogers,SA;Karl,IE;Hammerman,MR
通讯作者：
Hammerman,MR
影响因子：
15.9
作者：
BAYLIS, C
通讯作者：
BAYLIS, C
断奶大鼠增生性肾脏生长过程中胰岛素样生长因子 I、c-fos 和 c-jun 基因表达的时间变化。
DOI：
10.1210/endo.137.3.8603593
发表时间：
1996
期刊：
Endocrinology.
影响因子：
--
作者：
Mulroney,SE;Koenig,JI;Csikos,T;Pesce,C;Striker,L;LeRoith,D;Haramati,A
通讯作者：
Haramati,A
未成熟大鼠单侧肾切除术后胰岛素样生长因子-I (IGF-I) 和 IGF 受体基因的表达发生改变。
影响因子：
4.8
作者：
Mulroney,SE;Haramati,A;Werner,H;Bondy,C;RobertsJr,CT;LeRoith,D
通讯作者：
LeRoith,D