刺激大鼠蓝斑核区对胃电和胃运动的影响

用乌拉坦麻醉的大鼠,同步描记血压、胃电和胃运动,观察了刺激蓝斑核区对胃电和胃运动的影响,分析了其作用途径。实验结果表明,刺激蓝斑核区后血压平均升高60.5mmHg(P<0.001);胃电慢波的振幅由对照的0.52mV 减弱到0.18mV(P<0.001)。快波的振幅和频率也减少。胃内压平均下降到对照值的29.9％(P<0.001)。在横断颈髓的动物刺激蓝斑核区后血压的升高幅度明显减弱,平均升高9mmHg,升压效应的潜伏期明显延长;胃电慢波的振幅由对照的0.53mV 减弱到 0.24mV(P<0.001)。胃内压平均下降到对照值的45.1％。对胃电和胃运动的这种抑制效应可被切断迷走神经所完全消除。在事先切断迷走神经但脊髓仍保留完整的动物,刺激蓝斑核区使胃内压平均下降36.6％(P<0.01)。根据以上结果认为,蓝斑核区可能参与对胃电和胃运动的中枢性调节。此调节机制可能经由脊髓和迷走两条通路实现。

EFFECTS OF STIMUTION OF LOCUS COERULEUS ON THE ELECTRICAL AND MECHANICAL ACTIVITIES OF THE STOMACH OF RATS

Effects of stimulation of locus coeruleus (LC) on gastroelectrical activity andgastric motility were studied in rats under urethane anaesthesia. Following stimu-lation, the blood pressure was elevated 60.5 3.4mmHg (P<0.001), while theamplitude of the slow waves of electrogastrogram was diminished from controlvalue of 0. 52mV to 0. 18mV with little change of frequency. The fast waves weredecreased both in frequency and amplitude. Intragastric pressure was decreasedto 29.9% of the control value (P<0.001). After transection of cervical cord,stimulation of LC caused only an increase of 9 mmHg in blood pressure and a pro-longation of the latency of the pressor response, while the amplitude of slow wavesof electrogastrogram decreased from control value of 0.53mV to 0.24mV andintragastric pressure decreased to 45. 1% of the control value. These residualinhibitory effects were completely abolished by subsequent bilateral vagotomy. Inthe animals subjected to vagotomy only, while keeping spinal cord intact, stimulationof LC also reduced the intragastric pressure by 36.6%. It is suggested that theLC may be involved in the central regulation of electrical and mechanical activitiesof stomach, the effect heing mediated through both spinal and vagal pathway.