Effects of Dietary Salt Restriction on the Development of Renal Failure in the Excision Remnant Kidney Model

Kim, Kee-Hyuk; Kim, Sang-Yun; Kang, Yong-Joo; Maeng, Won-Jae; Kim, Kyo-Sun

J Korean Soc Pediatr Nephrol > Volume 3(2); 1999 > Article

J Korean Soc Pediatr Nephrol 1999;3(2): 170-179.

식이 sodium 제한 및 식이 sodium 제한에 따른 항고혈압제의 투여가 만성신부전증의 진행에 미치는 영향에 관한 실험적 연구

김기혁, 김상윤, 강용주, 맹원재, 김교순

¹건국대학교 의과대학 소아과학 교실
²건국대학교 의과대학 해부병리학 교실
³건국대학교 축산대학 사료영양학과
⁴건국대학교 축산대학 사료영양학과
⁵건국대학교 의과대학 소아과학 교실

Effects of Dietary Salt Restriction on the Development of Renal Failure in the Excision Remnant Kidney Model

Kee-Hyuk Kim, Sang-Yun Kim, Yong-Joo Kang, Won-Jae Maeng, Kyo-Sun Kim

¹Departments of Pediatrics, College of Medicine, Konkuk University
²Departments of Pathology, College of Medicine, Konkuk University
³Department of Feed and Nutritional Science, College of Animal Husbandry, Konkuk University
⁴Department of Feed and Nutritional Science, College of Animal Husbandry, Konkuk University
⁵Departments of Pediatrics, College of Medicine, Konkuk University

ABSTRACT

Purpose: To evaluate whether or not sodium restriction had its own beneficial effect and increased the efficiency of the anti-hypertensive drugs on the progression of renal failure.
Methods: We studied using the excision remnant kidney model. Treatment groups were as follows: 5/6 nephrectomy and a 0.49% (normal-high) sodium diet (NN); 5/6 nephrectomy and a 0.25% (normal-low) sodium diet (LN); 5/6 nephrectomy, a 0.49% sodium diet and enalapril (NNE); 5/6 nephrectomy, a 0.49% sodium diet and nicardipine (NNN); 5/6 nephrectomy, a 0.25% sodium diet and enalapril (LNE); 5/6 nephrectomy, a 0.25% sodium diet and nicardipine (LNN). Both diets were isocaloric and had the same content of protein, phosphorus and calcium. Proteinuria, remnant kidney weight, mesangial expansion scores, and glomerular volume were assessed.
Results : Blood pressure tended to be lower in LN compared to NN (P<0.05). NN developed progressive hypertension. LNE, LU, NNE, and NNN reduced blood pressure. LNE, LNN, NNE, NNN, and LN had significantly less proteinuria than NN at 16 weeks (P<0.05). At 24 weeks, LN developed proteinuria (82 mg/day), which were lessened in LNE (54 mg/day) and not lessened in LNN (76 mg/day). Mesangial expansion scores were significantly less in LN rats compared to those in NN rats. Glomerular volumes at 24 weeks in LN rats were significantly less compared to those at 16 weeks in NN rats. Mesangial expansion scores and glomerular volumes at 4, weeks, 12 weeks, and 24 weeks were not different among LN, LNE, and LNN groups.
Conclusion : Dietary salt restriction lessens renal damage, at least in part, by inhibiting compensatory renal growth and reducing blood pressure. Enalapril was particularly successful in reducing proteinuria and glomerular injury when combined with dietary salt restriction.

Key words: Chronic Renal failure | Moderate sodium restriction | Antihypertensive drugs | Remnant kidney model