环境温度对中华蟾蜍间脑神经元电活动的影响

Impact of Ambient Temperature on Electrical Activities of Bufo Gargarizans Diencephalon Neurons

应用微电极电生理技术记录不同环境温度下中华蟾蜍间脑神经元电活动,观察环境温度对中华蟾蜍间脑神经元电活动的影响,探讨生理性体温调节在中华蟾蜍体温调节中的作用.结果,中华蟾蜍间脑松果体和下丘脑视前区前部神经元的放电频率和放电幅度随环境温度的升高而升高,呈兴奋性变化,相关显著,表明松果体和下丘脑视前区前部神经元对高温环境较敏感,参与了降温过程的体温调节,但下丘脑视前区前部较松果体变化明显;下丘脑视前区后部神经元的放电频率和放电幅度随温度的升高而降低,呈抑制性变化,相关显著,表明下丘脑视前区后部神经元对低温敏感,参与了升温过程的体温调节.

The objective of this study is to probe the impact of ambient temperature on physiological thermar- egulation in Bufo gargarizans. The microelectrode technique was employed to record extracellularly spontaneous electrical activities of neurons in diencephalon of Bufo gargarizans at different ambient temperatures. Our results show that, as ambient temperature increases, the firing frequency, amplitude of neurons of anterior hypothalamus and pineal gland were also found increased. Significant correlations among them were observed, indicating that neurons in anterior hypothalamus and pineal gland are sensitive to the high temperature environment, and they are all involved in body temperature adjustment. We also found that changes in the anterior hypothalamus were more pronounced than those in pineal gland. The firing frequency and amplitude of neurons in posterior preoptic areas were seen decreased as the ambient temperature increased, suggesting that there was an inhibition process going on n posterior preoptic areas. This mechanism indicates that neurons in the posterior preoptic area are more sensitive o low temperatures and they play important roles in the process of fervescence.