Biochemical Studies on Oral Toxicity of Ricin. I. Ricin Administered Orally Can Impair Sugar Absorption by Rat Small Intestine

• Published in: Chemical & pharmaceutical bulletin Vol. 31; no. 9; pp. 3222 - 3227
• Main Authors: ISHIGURO, MASATSUNE, MITARAI, MASAKO, HARADA, HIROMICHI, SEKINE, ICHIRO, NISHIMORI, ISSEI, KIKUTANI, MOTOSUKE
• Format: Journal Article
• Language: English
• Published: Tokyo The Pharmaceutical Society of Japan 1983; Maruzen; Japan Science and Technology Agency
• Subjects: Animals; Biological and medical sciences; Carbohydrate Metabolism; D-glucose; Glucose - metabolism; In Vitro Techniques; Intestinal Absorption - drug effects; Male; Medical sciences; Mice; mucosa; Plant poisons toxicology; Rats; Rats, Inbred Strains; ricin; Ricin - toxicity; Ricinus communis; small intestine; sugar; Toxicology; Rat; Digestive system; Rodentia; Oral administration; Glucose; Small intestine; Toxin; Vertebrata; Mammalia; Absorption; Dicotyledones; Animal; Angiospermae; Plant origin; Euphorbiaceae; Spermatophyta; Intoxication
• ISSN: 0009-2363; 1347-5223
• DOI: 10.1248/cpb.31.3222

Rats intoxicated orally with ricin (30mg/kg) showed clear signs of sickness and all died within 36 h. Dying animals shivered and lost body weight. The animals suffered from severe diarrhea within 5-10 h and profuse watery purging. In all intoxicated animals, large amounts of watery fluid were seen in the small intestine, but no significant changes in other organs were observed on gross examination. The effect of oral administration of ricin (30 mg/kg) on D-glucose absorption by rat small intestine was examined by the in vitro everted sac method. The amount of D-glucose absorbed by the small intestine derived from ricin-treated rats was 61.8 μg per 100 mg of tissue per hour or 30% of that of normal rats (206 μg/100 mg of tissue/h) at 5 h after intoxication. Absorptions of D-galactose, D-mannose, and 3-O-methylglucose by the small intestine of ricin-treated rats were 66, 46, and 80% of those of the normal intestine, respectively. Light microscopic examination revealed significant changes such as loss of villi and delay of the regeneration of absorptive epithelials of the small intestine at 5 h after administration. From these results, it was inferred that ricin acts primarily on the intestinal mucosa and impairs sugar absorption.