Toxic effects of methylcellulose solution on the liver, spleen and kidney in the Sprague-Dawley(SD) rats following repeated oral or intravenous administration

Methylcellulose의 경구 및 정맥내 반복 투여가 SD랫드의 간장, 비장 및 신장에 미치는 독성학적인 영향

This experiment was carried out to study the toxic effect of solublized methylcellulose (MC). Sprague-Dawley rats were dosed with 1%(w/v) MC in 0.9% saline by gavage at a dose of 10ml/kg b.w/day or by intravenous injection at a dose of 5ml/kg b.w/day for 28 days. Clinical signs were observed once a day. Body weights, water and food consumptions were measured and urinalysis was performed several times during the experiment. Rats were sacrificed on days 3, 7, 15 and 28 for hematology, blood chemistry, organ weights and histopathology. The relative weight of the spleen and foamy cells of the spleen were increased in the gavage group. Body weight gain, food consumptions, the values of RBC, Hb, MCH, Hct, serum proteins, glucose, bilirubin, AST, and ALP were decreased in I.V. treatment group. On the other hand, water consumptions, the values of serum cholesterol, creatinine, and BUN were increased. Microscopic findings were granulomas, distended sinusoids, and hypertrophy of Kupffer cells with vacuoles in the liver. Spleen exhibited granuloma, increased extramedullary hematopoiesis, and congestion. Kidney exhibited foamy cells in the glomeruli, distension of the tubules. The findings appeared more severe when the treatment was extended. In conclusion, MC solution is not a safe vehicle for intravenous administration because of the toxic effects on the liver, kidney and spleen. In addition, a long-term and large dosage of oral administration of MC appears to be unsafe also and needs to be investigated further.