Induction of micronucleus in NSC19 motoneuron cell line by genotoxic chemicals.

Abstract

Micronucleus is formed when chromosomal fragments behave independently of remaining chromosomes during the division of cells damaged by genotoxic agents, and the frequency of micronucleus is considered to reflect genotoxic damage to cells. In order to obtain a simple, fas and low-cost assay system to evaluate genotoxicity in the nervous system, we utilize the micronucleus test in a NSC19 mouse neuroblastoma x spinal motoneuron hybrid cell line which was exposed to 4-nitroquinoline-N-oxide (4NQO). There was a significant increase in number of micronuclei in NSC19 cells following 24 hr exposure to 4NQO. Two other genotoxic chemicals, cytosine beta-D-arabinofuranoside (AraC) and ethylmethanesulfate (EMS), similarly increased the frequency of micronucleated cells in a dose-dependent manner. The micronucleus test described in the present study is useful as a short-term genotoxicity evaluation system for cells of nervous system origin.