Abstract
The effects of various concentrations of the nerve growth factor (NGF) and of dimethylsulfoniopropionate (DMSP) on the outgrowth of neurites from pheochromocytoma (PC12) cells were examined singly or in combination on an RPMI 1640 medium containing 10% horse serum, 5% fetal bovine serum, penicillin and streptomycin in collagen-coated Petri dishes by increasing the incubation times up to 4 d. The results indicated that NGF significantly accelerated the number of neurite-bearing cells, which reached a maximum at concentrations of more than 0.5 ng/mL among the various concentrations of NGF on the 4th day. The combined effects of the various concentrations (10−6 -10−3 M) of DMSP with NGF (5 ng/mL) on the growth and the number of neurite-bearing cells were then examined, which demonstrated that all the concentrations of DMSP restricted the growth of the cells to various extents but that the concentration of DMSP at 10−4 M with the NGF more highly accelerated the number of neurite-bearing cells than did the NGF alone during the experimental period.
