Protective effect of nicardipine treatment on renal microanatomical changes in spontaneously hypertensive rats

The effects of nicardipine administration on kidney morphology were studied in spontaneously hypertensive rats (SHR). Male 12-week-old SHR received an oral dose of 1 mg/Kg/day of nicardipine or vehicle for 8 weeks Age-matched Wistar-Kyoto rats were used as normotensive reference animals. At 20 weeks, the non treated SHR exhibited hypertension, albuminuria, decreased urinary sodium excretion and renal microanatomical changes. These changes were characterized by vascular alterations consisting in hypertrophy of the tunica media accompanied by a decrease of luminal surface. Glomerular changes consisting primarily in signs of glomerulosclerosis of varying degrees were noticeable in the kidneys of SHR. Treatment with nicardipine significantly reduced blood pressure and albuminuria and increased urinary sodium excretion. Moreover, hypertrophy of the tunica media and the luminal surface were decreased and increased respectively in nicardipine-treated SHR. The above results suggest that treatment with nicardipine reduces blood pressure in SHR and counteracts hypertension-dependent changes in the morphology of the kidney. The protective effect of the drug on hypertensive changes of renal microanatomy probably have functional relevance given of the influence of nicardipine treatment on albuminuria and urinary sodium excretion in SHR.