Edin Benoni B
Physiology Section, Dept. of Integrative Medical Biology, University of Umeå, S-901 87 Umeå, Sweden.
J Neurophysiol. 2004 Dec;92(6):3233-43. doi: 10.1152/jn.00628.2004.
Microneurographical recordings from 24 slowly adapting (SA) and 16 fast adapting (FA) cutaneous mechanoreceptor afferents were obtained in the human radial nerve. Most of the afferents innervated the hairy skin on the back of the hand. The afferents' receptive fields were subjected to controlled strains in a ramp-and-hold fashion with strain velocities from 1 to 64%.s(-1), i.e., strain velocities within most of the physiological range. For all unit types, the mean variation in response onset approached 1 ms for strain velocities >8%.s(-1). Except at the highest strain velocities, the first spike in a typical SAIII unit was evoked at strains <0.5% and a typical SAII unit began to discharge at <1% skin strain. Skin strain velocity had a profound effect on the discharge rates of all classes of afferents. The "typical" peak discharge rate at the highest strain velocity studied was 50-95 imp/s(-1) depending on unit type. Excellent fits were obtained for both SA and FA units when their responses to ramp stretches were modeled by simple power functions (r2 > 0.9 for 95% of the units). SAIII units grouped with SAII with respect to onset latency and onset variation but with SAI units with respect to dynamic strain sensitivity. Because both SA and FA skin afferents respond strongly, quickly, and accurately to skin strain changes, they all seem to be able to provide useful information about movement-related skin strain changes and therefore contribute to proprioception and kinesthesia.
在人的桡神经中获取了来自24条慢适应（SA）和16条快适应（FA）皮肤机械感受器传入纤维的微神经图记录。大多数传入纤维支配手背的有毛皮肤。以1%至64%·s⁻¹的应变速度（即大多数生理范围内的应变速度），以斜坡-保持方式对传入纤维的感受野施加可控应变。对于所有单位类型，当应变速度>8%·s⁻¹时，反应起始的平均变化接近1毫秒。除了在最高应变速度下，典型的SAIII单位在应变<0.5%时诱发第一个峰电位，典型的SAII单位在皮肤应变<1%时开始放电。皮肤应变速度对所有类别的传入纤维的放电率有深远影响。根据单位类型，在所研究的最高应变速度下，“典型”的峰值放电率为50 - 95次冲动/s⁻¹。当用简单幂函数对SA和FA单位对斜坡拉伸的反应进行建模时，拟合效果极佳（95%的单位r²>0.9）。SAIII单位在起始潜伏期和起始变化方面与SAII单位归为一组，但在动态应变敏感性方面与SAI单位归为一组。由于SA和FA皮肤传入纤维对皮肤应变变化都有强烈、快速且准确的反应，它们似乎都能够提供有关与运动相关的皮肤应变变化的有用信息，因此有助于本体感觉和运动觉。
