LHRH对灌流的雄性大鼠垂体细胞分泌LH的自身激发作用

A self-priming effect of LHRH on LH secretion in perifused anterior pituitary cells of adult male rats

为了研究LHRH(促黄体激素释放激素)对雄性大鼠垂体细胞分泌LH(促黄体激素)是否有自身激发作用,我们用不同幅度(1×10^(-10)～1×10^(-8) mol/L)和不同频率(1～4脉冲/小时)的LHRH脉冲刺激灌流的SD雄性大鼠垂体前叶细胞,观察了在灌流系统中细胞LH的分泌反应。结果表明,在高幅度(1×10^(-9)mol/L或更大)和高频率(3脉冲或更高)LHRH脉冲作用下,灌流的垂体细胞可表现自身激发作用,即在LHRH刺激一定时间后,同样的LHRH刺激产生更大的LH释放。但是,低幅度(1×10^(10)mol/L)LHRH即使在高频率下也不能显著地改变LH反应性。上述实验说明:离体成年雄性大鼠垂体前叶细胞存在对LHRH的自身激发作用,这种自身激发作用的产生主要依赖于LHRH脉冲的幅度和频率。

In order to determine whether a self - priming effect of LHRH on LH secretion exists in anterior pituitary cells of adult male rats, dispersed anterior pituitary cells of Sprague -Dawley male rats were stimulated with LHRH pulses of different amplitudes (1 X 10^(-10)～1×10^(-8) mol/L) or frequencies (1～4 pulses/h) in a perifusion system. The results showed that LHRH pulses with high amplitude (1×10^(-9) mol/L or higher) at frequencies of 3(or more) pulses per hour could induce a LHRH self - priming effect. However, low amplitude of LHRH(1×10^(-10) mol/L) at high frequency failed to affect LH responsiveness significantly. Our data indicate that this priming effect exists in anterior pituitary cells of male rats, and the generation of self-priming effect is mainly dependent on the frequency and amplitude of LHRH pulse.