Hill J M
Department of Kinesiology, Division of Natural and Applied Sciences, Hashinger Science Center, Rm. 202, Chapman University, Orange, CA, USA.
Brain Res. 2000 Feb 21;856(1-2):240-4. doi: 10.1016/s0006-8993(99)02366-5.
The discharge of single unit group III (n=7) and group IV (n=8) phrenic afferent fibers was recorded during rhythmic diaphragmatic contractions before and after the onset of fatigue. Compared to pre-fatigue impulse activity, group IV, but not group III, phrenic afferent fibers discharged more (p<0.05) during rhythmic diaphragmatic contractions when the diaphragm was fatigued. This increase in group IV fiber discharge during diaphragmatic fatigue provides electrophysiological evidence consistent with the notion that group IV phrenic afferent fibers comprise the afferent arm of a fatigue-induced inhibitory reflex originating in the diaphragm.
在疲劳开始前后的节律性膈肌收缩过程中,记录了单单位III组(n = 7)和IV组(n = 8)膈传入纤维的放电情况。与疲劳前的冲动活动相比,当膈肌疲劳时,在节律性膈肌收缩过程中,IV组而非III组膈传入纤维放电增多(p<0.05)。膈肌疲劳期间IV组纤维放电的这种增加提供了电生理证据,支持IV组膈传入纤维构成源自膈肌的疲劳诱导抑制反射的传入支这一观点 。