Developmental Neurotoxicity Of Mice After Postnatal Exposure To Of M-tolyl Methylcarbamate

Backgroundm-tolyl methylcarbamate(MTMC)is one of carbamates pesticide, humans are exposed to MTMC, from various environmental sources. MTMC is neurotoxicin that include pesticidal toxicology, neural developmental toxicity. Recently the study showed that chronic and low dosage exposured to MTMC seemed to be more at risk for recognization, psychology deficts, developing Parkinson's disease and other neurodegenerative disease. But chronic and low dosage exposured to MTMC that induced neural developmental toxicity still is unknown and unconcern.ObjectiveTo explore the sensitive neurobehavior indexs of exposured to MTMC in mice by a series methods of behavior, the results can be referenced in neural developmental toxicity in human. To study cholinesterase activity in brain and the expression of GAP-43. To investigate neural developmental toxicity mechanism of MTMC. MethodsAll mice except controls were injected with different doses of MTMC (0.05, 0.5, 5 mg·kg-1, i.p.) every other day on postnatal day (PND) 3-13, the PBS- and DMSO- treated mice served as controls. After exposured to MTMC, observe physiological growth, sensory movement and loctomotion and harmony ability of little mouse by a series methods of developmental neurobehavior, learning and memory ability in mice by Morris water maze, spontaneous motor activity by hole board test, open field, wire suspension and balance beam test detect balance capability, anxiety by black-white alley, levels of AchE were measured. The protein expression of GAP-43 was observed by Western blotting.The data were analyzed with SPSS 10.0ResultsThere was a significant delay in eye opening in MTMC-exposure groups and erupting of inferior tooth in the high dose group as compared with DMSO control. MTMC-exposure induced reversible effects on sensorimotor activity which were measured by cliff avoidance test( PND 5 ) and horizontal bar task ( PND 70). No significant changes in open-field activity were observed. Significant differences in the time in the target quadrant and number of platform-site crossovers in probe trial of MWM test were evident in the MTMC-exposure mice for the high dose group compared to the control group. The protein expression of GAP-43 increased compared to DMSO control.ConclusionsThe results suggest that early postnatal exposure to MTMC affects the physiological growth and developmental neurobehavior in the suckling mice, also affects spatial memory in adult mice.