LACK OF PROMOTING EFFECT OF PROLINE ON BILE-DUCT CANCER DEVELOPMENT IN DIMETHYLNITROSAMINE-INITIATED HAMSTER LIVERS

Bile duct hyperplasia caused by proline is believed to represent a che mical effect of the liver fluke, Fasciola hepatica, and the resultant cell division might be expected to play a role as a tumor promoter. To investigate the potential promoting effect of proline on bile duct ca ncer development, Syrian hamsters were therefore divided into 8 treatm ent groups: dimethylnitrosamine (DMN) + proline intraperitoneally (i.p .); DMN + proline s.c.; DMN + saline i.p.; DMN + saline s.c.; proline i.p.; proline s.c.; saline i.p.; and saline s.c. DMN was injected i.p. at 20 mg/kg to the animals 2 weeks prior to commencement of proline t reatment, whereby 1 ml of a 2 M solution was given by i.p. or s.c. inj ection 3 times a week for 20 weeks. At the end of week 42, assessment of preneoplastic lesion development did not reveal any significant mod ulating influence of proline on DMN-initiated lesion development nor d id it itself cause persistent bile duct hyperplasia. (C) 1994 Wiley-Li ss, Inc.