J Korean Med Sci.  1995 Oct;10(5):352-359. 10.3346/jkms.1995.10.5.352.

Light microscopic and electron microscopic features of cyclosporine nephrotoxicity in rats

• Kim JY
• Suh KS

• KMID: 644901
• DOI: http://doi.org/10.3346/jkms.1995.10.5.352

Abstract

In order to clarify morphologic changes associated with cyclosporine (CS) nephrotoxicity, CS in ethyl alcohol at 25 mg/kg/day i.p. was administered to male Sprague-Dawley rats for periods of 1 to 8 weeks. Mean systolic BP was slightly increased in the CS group at 4 weeks (p < 0.05), but there was no difference compared to a control group at 8 weeks. Blood urea nitrogen was significantly elevated at 4 weeks and continued to rise (p < 0.005), whereas serum creatinine was elevated at 8 weeks. Microscopic examination of the kidneys from CS-treated rats at one week revealed cytoplasmic vacuolization in all segments of the proximal tubules, tubular inclusion bodies, and peritubular capillary congestion. Ultrastructurally, some vacuoles were neutral fat droplets, while others appeared as single membrane-bound structures due to dilatation of the endoplasmic reticulum. The tubular inclusion bodies were enlarged autolysosomes filled with distorted mitochondrial fragments. At two weeks, tubular regeneration was prominent, in addition to the above mentioned toxic tubulopathy. At four weeks, focal areas of interstitial fibrosis and tubular atrophy associated with cystic dilatation were seen. At 8 weeks, interstitial and intratubular microcalcification were present, in addition to patchy foci of interstitial fibrosis, but vascular lesions were not demonstrated. Although renal tubular changes characterized by vacuolization, inclusion bodies, and microcalcification and interstitial fibrosis are not specific for CS toxicity, these changes are commonly found in both humans and rats at high doses of CS.

Keyword

Cyclosporine nephrotoxicity; Sprague-Dawley rats; Endoplasmic reticulum; Toxic tubulopathy

MeSH Terms

Acute Disease
Animal
Body Weight/drug effects
Chronic Disease
Cyclosporine/*toxicity
Immunosuppressive Agents/*toxicity
Kidney Diseases/*chemically induced/*pathology
Kidney Tubules/drug effects/pathology/ultrastructure
Male
Microscopy, Electron
Rats
Rats, Sprague-Dawley