Muscle afferent responses to isometric contractions and relaxations in humans

摘要: 1. One hundred and two single afferents from the finger extensor muscles of humans were studied with microneurography technique. 2. The provisionally classified as primary muscle spindle (62/102), secondary (22), Golgi tendon organ (18) on basis their responses to four tests: 1) ramp-and-hold stretch, 2) 20- 50-Hz small-amplitude sinusoidal stretch superimposed 3) maximal isometric twitch contraction, 4) sensitization. 3. response profiles three unit types analyzed during slowly rising contraction terminating an abrupt relaxation. About 75% (61/84) all increased discharge whereas was reduced for remaining afferents. All organs contraction. 4. level extrafusal at which a afferent its rate often varied trial trial, speaking against fixed fusimotor recruitment individual ending. 5. In 70% afferents, distinct burst impulses appeared when subject rapidly relaxed after more common usually much prominent than reaching instantaneous rates well above 100 Hz. 6. Whereas displayed phase, only one them exhibited acceleration close relaxation phase. However, this could clearly be identified being different nature bursts.(ABSTRACT TRUNCATED AT 250 WORDS)