An in vitro study of trophic activity on facial motoneuron by soluble substances derived from Schwann cells of rats / 北京大学学报(医学版)

ABSTRACT

Objective: To compare trophic effects of soluble substances derived from Schwann cells (SC) of neonatal and Wallerian degenerating segments of rats on facial motoneuron (FMN) cultures. Methods: Serum-free conditioned media of Schwann cell cultures (SC-CM) from facial and sciatic nerves of neonatal and Wallerian degenerating segments in adult rats were individually collected and concentrated by ultra-filtration with molecular weight cut-off at 30 000 and 10 000. The growth activities of FMNs in vitro were determined by means of MTT assay under the condition of serum-free medium added with different components of concentrated SC-CMs (SC-CMCs). The absorbance values were then statistically analyzed. Results: Survival and growth rate of FMN cultures in four kinds of SC-CMCs were significantly higher than that in media both with serum and non-serum and the difference between SC-CMCs was not statistically significant (P>0.05). Neurotrophic molecules were predominantly protein or peptide components with relative molecular weight larger than 30 000 and their trophic activity was positively related to total protein concentration in SC-CMCs. Conclusion: There were soluble trophic molecules with relative molecular weight larger than 30 000 for survival and neurite growth of FMN cultures in media with SC-CMCs derived from facial and sciatic nerves of neonatal rats and with SC-CMCs derived from Wallerian degenerating facial and sciatic nerves of adult rats. It might be reasonable to choose SC from sciatic nerves of rats on account of the findings from SC cultures on facial motoneurons.