UT-B-deficient mice develop renal dysfunction and structural damage

BMC Nephrology

Baoxue Yang³  Xuejian Zhao²  Jing Su²  Dan Zhao²  Tianluo Lei³  Yan Meng²  Lei Zhou¹ 

[1]Department of Pathology, Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, China

[2]Prostate Diseases Prevention and Treatment Research Center, Department of Pathophysiology, Norman Bethune College of Medicine, Jilin University, Changchun, China

[3]Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, China

关键词: knock-out;    UT-B;    kidney;    renal function;    urea transporter;   

Others  :  1083207
DOI  :  10.1186/1471-2369-13-6

 received in 2011-04-29, accepted in 2012-01-30,  发布年份 2012

【 摘 要 】

Background

Urea transporter UT-B is the major urea transporter in erythrocytes and the descending vasa recta in the kidney. In this study, we investigated the effects of long-term UT-B deficiency on functional and structural defect in the kidney of 16-and 52-week-old UT-B-null mice.

Methods

UT-B-knockout mice were generated by targeted gene disruption and lacked UT-B protein expression in all organs. The urinary concentrating ability of mice was studied in terms of daily urine output, urine osmolality, and urine and plasma chemistries. Changes in renal morphology were evaluated by hematoxylin and eosin staining.

Results

The UT-B-null mice showed defective urine concentrating ability. The daily urine output in UT-B-null mice (2.5 ± 0.1 ml) was 60% higher and urine osmolality (985 ± 151 mosm) was significantly lower than that in wild-type mice (1463 ± 227 mosm). The 52-week-old UT-B-null mice exhibited polyuria after water deprivation, although urine osmolality was increased. At 52 weeks of age, over 31% of UT-B-null mice exhibited renal medullary atrophy because of severe polyuria and hydronephrosis.

Conclusions

Long-term UT-B deficiency causes severe renal dysfunction and structural damage. These results demonstrate the important role of UT-B in countercurrent exchange and urine concentration.

【 授权许可】

   
2012 Zhou et al; licensee BioMed Central Ltd.

【 图 表 】

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