RESUMEN
Objective To explore different doses of calcium 5-formyltetrahydrofolate(CF)for protecting enteral mucosa after chemotherapy of high-dose methotrexate(HD-MTX) in rats.Methods Sixty of 6 weeks old Wistar rats were divided into 5 groups in random,12 rats every group.Group A:control group,normal sodium(NS) intraperitoneal injection only;Group B to E:after HD-MTX intraperitoneal injection(120 mg/kg),1% CF(CF dose amounts to 1% of total MTX dose) for group B,2% CF for group C,8% CF for Group D and empty for group E.For group B、C and D,CF were intramuscular injected after 12 hours of MTX used,q6h?7 times.Rats were killed after 18 hours of the last time of CF.Morphous of jejunum dissection were observed and length of intestinal villus and depth of crypt were mea-sured.Results For group A,jejunum walls were thick and elastic and intestinal villus were close and orderly.Jejunum walls were congestive,swollen and thin,length of intestinal villus and depth of crypt reduced both in group B to E.These were most obvious in group E,and were secondary in group B.Statistical analysis showed that significant difference in effect existed between group B,C,D,E and group A(Pa0.05).Conclusion MTX can damage in intestinal mucosa of rats,CF can reduce this damage,excessive low doses of CF can't play this role.