Abstract: ObjectiveTo study the effect of the hyperthmia and cigarette smoking on the neonate rat's neurobehavioral.MethodsRats pregnant for 10 days were exposed to high temperature(41℃ or 42℃).Water-soluble substances containing cigarette smoking(1.10 cigarette/20 g rat)were given through subcutaneous inject at 2,4,6,8,10,12,14 days of gestation.The neonate rat's neurobehavioral(the appearance of four physiological markers,the acquisition of four reflexes,learning and memory)was observed.ResultsIn contrast to the control group and 37℃ group,when pregnant rats were exposed to high temperature(41℃ and 42℃)the neonate rats were delayed for the appearance of four physiologic markers(eye opening、pinna detachment、hair growth and tooth growth),the age of acquisition of four reflexes(surface righting,air righting,virual placing and auditory orienting)and the time of learning and memory(P<0.01).There was significant combined effect between the sustained hyperthermia of longer time and cigarette smoking,and there was a significant difference compared with the neurobehavioral of those only in single hyperthermia(P<0.01).ConclusionThe sustained hyperthermia combined with cigarette smoking can increasely delayed the neurobehavior growth of neonate rats.