Schäfer S S
Abteilung Neurophysiologie Medizinische Hochschule Hannover.
EEG EMG Z Elektroenzephalogr Elektromyogr Verwandte Geb. 1992 Mar;23(1):12-9.
The discharge frequency of primary muscle spindle afferents was recorded out of the tibial anterior muscle of the cat under a ramp-and-hold stretch. The rate of the ramp stretch was increased stepwise from 1 to 100 mm/s. Its amplitude was kept constant and was 7 mm. Whereas the initial length of the host muscle was enhanced in steps of 3 mm to reach a maximal augmentation of the muscle length of 12 mm. The decrease of the discharge frequency from the dynamic peak (the discharge frequency at the end of the dynamic phase of stretch) onto the static value (the discharge frequency 3 s after the end of the dynamic phase of stretch) comprises the receptor adaptation which had been analysed. Two components could be defined in the course of the adaptation, the fast and the slow decay (fig. 2). The border between the two components is the discharge frequency of static maximum. The static maximum is the first discharge frequency at the beginning of static phase of stretch. The static maximum increases with the initial length (fig. 3) and is independent of the stretch rate. The fast decay, the decrease of the discharge frequency from the dynamic peak onto the static maximum, lasts for only some 10 ms. The degree of the fast decay turns out to the dependent on the rate of ramp stretch by a power function whose exponent has in the mean a value of 0.5 (fig. 4).(ABSTRACT TRUNCATED AT 250 WORDS)
在斜坡-保持拉伸条件下，记录猫胫骨前肌中初级肌梭传入纤维的放电频率。斜坡拉伸的速率从1毫米/秒逐步增加到100毫米/秒。其幅度保持恒定，为7毫米。而宿主肌肉的初始长度以3毫米的步长增加，以达到肌肉长度最大增加12毫米。从动态峰值（拉伸动态阶段结束时的放电频率）到静态值（拉伸动态阶段结束后3秒的放电频率）的放电频率降低包括已分析的感受器适应。在适应过程中可定义两个成分，快速衰减和缓慢衰减（图2）。两个成分之间的界限是静态最大值的放电频率。静态最大值是拉伸静态阶段开始时的第一个放电频率。静态最大值随初始长度增加（图3），且与拉伸速率无关。快速衰减，即放电频率从动态峰值降低到静态最大值，仅持续约10毫秒。快速衰减的程度通过幂函数取决于斜坡拉伸的速率，其指数平均为0.5（图4）。（摘要截选至250字）
