摘要
１只实验犬探讨了咖啡因对正常及疲劳后隔肌收缩功能的作用。以ＰｄｉＦ曲线作为评价膈肌收缩力的指标。膈肌疲劳模型用连续电刺激两侧膈神经的方法制备。结果表明，无论在正常或疲劳后膈肌，咖啡因（２０ｍｇ／ｋｇ）均可显著增强其收缩力。而且，咖啡因对膈肌的正性肌力作用与心输出量、肺总阻力及动态肺顺应性变化无关。还讨论了咖啡因对膈肌肌力影响的可能机制，指出咖啡因在治疗慢阻肺呼吸肌疲劳方面可能有一定临床价值。
The effect of caffeine on diaphragmatic contractility and fatigue has been investiga- ed in 2 1 dogs. Diaphragmatic contractility was assessed by measuring transdiaphragmatic pressure(Pdi)during supermaximal stimulation of the phrenic nerves at different frequencies, In protocol1 , the effect of caffeine on contractility of non- fatigued diaphragm was studied in 7 dogs. Caffeineinfusion increased Pdi significantly at all frequencies of stimulation. In protocol 2 , diaphragmatic fa-tigue was induced by electrophrenic stimulation(30Hz, duty cycle 1.0 ,for 30min ). The recoveryprofile after fatigue was observed in 5 dogs. In another group of 9 dogs, caffeine was infused duringstable fatigue period and Pdi increased significantly at. all frequencies of stimulation aftercaffeine infusion. The increase in Pdi was not due to changes in cardiac output norlung mechanics(Cdyn and Rtot), as neither of which changed significantly after caf-feine infusion. We conclude that caffeine improves muscle contractility both in non- fatigued and fatigued diaphragm in dogs
出处
《解放军医学杂志》
CAS
CSCD
北大核心
1994年第1期3-5,共3页
Medical Journal of Chinese People's Liberation Army
关键词
咖啡因
膈肌疲劳
跨膈压
心输出量
犬
Caffeine
Diaphragmatic fatigue
Pdi
Cardiac output
Dogs
