Effect of Extracorporeal Shock Waves on Immature Rat Kidney

Jang, Seok Heun; Choi, Hak Ryong; Shim, Bong Suck; Kwon, Sung Won

Abstract

Although extracorporeal shock wave lithotripsy(ESWL) has been used to treat renal stones for several years, little is known of its effect on developing tissue. To study the long-term bio-effects of this mode of treatment on the immature animal, we used 32 Sprague-Dawley rats at 4weeks of age and divided 4 groups which consisted of 8 rats respectively. They were weighted and left nephrectomy was then performed. 10 days later, 3 groups received extracorporeal shock waves (16 kV) of 500, 1,000, 1,500 times respectively to the right kidney using Lithoring(3rd generation pendulum-ESWL), but control group didn't received shock waves. They were allowed to mature, and at 16 weeks of age they were evaluated for weight and serum creatinine. The right kidney was then harvested, weighted and stained with hematoxylin and eosin. There were no significant changes in over-all animal growth, renal growth and renal function in the post-treatment groups when compared to the control group. At comparison of histological changes, the grade of interstitial nephritis was proportional to the number of shock wave received In conclusion, shock waves delivered to immature animals do not significantly affect animal growth, renal growth and function, but it can cause significant permanent histological renal changes even at low doses and further studies are needed with an adult control group in an attempt to delineate whether the immature kidney is, indeed, more vulnerable to the shock waves.