RECOVERY CURVES OF THRESHOLDS OF MUSCLE SPINDLE, LEAF-LIKE AND TENDON RECEPTORS IN THE FROG SARTORIUS MUSCLE AFTER AN ANTIDROMIC DISCHARGE

  • 伊藤 文雄
    Department of Physiology, School of Dentistry, Aichi-Gakuin University

この論文をさがす

抄録

1. The thresholds of the sensory endings of single spindle, leaf-like and tendon receptors in the frog sartorius muscle were measured with pressure test stimulations applied at different periods after a conditioning antidromic stimulation.<BR>2. The threshold for the first discharge from the spindle receptor excited by a threshold pressure stimulation decreased transiently at approximately 30 msecafter the absolute refractory period of 1.1-1.6 msec after an antidromic discharge, and increased at 60 msec, then returned to the normal level for 650 msec.<BR>3. In fresh preparations, a recurrent discharge appeared at 30 msec after an antidromic discharge, without test stimulation.When the muscle was extended, the periods of the appearance of the recurrent discharge and of the transient decrease of the threshold shortened, and the recovery curves of the threshold closed to the normal level over all of its course.<BR>4. The threshold for the second discharge from the spindle produced by a larger mechanical stimulation returned to normal for 40-60 msec after an antidromic discharge, during which no transient decrease was observed.<BR>5. The leaf-like receptors responded with only one discharge to different strengths of the pressure stimulation.The thresholds, which were higher than those of the spindle, decreased linearly after the absolute refractory period of up to 20 msec, and returned to normal 150 msec after an antidromic discharge.<BR>6. The recovery curve of the threshold of tendon receptors could be drawn only for 5 out of 18 receptors tested, and it was suggested that in the remaining receptors the antidromic discharge may not have propagated along all of the branches beyond a node in the vicinity of the sensory endings, at which the parent axon may have divided into four or more branches. The threshold returned to normal approximately 300 msec after the absolute refractoryperiod of from 2.2 to 4.5 msec, without any transient decreases during it course.

収録刊行物

被引用文献 (1)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ