METABOLITE EFFECTS OF GROUP III AND IV MUSCLE AFFERENTS

描述（改编自申请人的摘要）： 在本申请中提出的实验是确定是否动态 运动对第三组和第四组肌肉放电的影响不同 传入神经在去大脑未麻醉的猫中， 中脑运动区的电和化学刺激。的 不同程度的运动和缺血对脑组织放电的影响 将确定第III和第IV组肌肉传入。将特别注意 运动后循环阻断时传入神经的反应， “纯”代谢反射刺激。还将注意以下方面所发挥的作用： 环氧合酶代谢物和缓激肽在刺激这些传入过程中 动态练习最后，所提出的实验将检查 肌肉疲劳对第III组和第IV组传入运动反应的影响。 这些细纤维传入已被假设为负责 疲劳性肌肉收缩时α运动神经元的反射抑制 在人类身上。对动力性运动的自主神经反应和代偿性反应良好 建立并包括交感神经放电的增加， 血管、心率、收缩性、呼吸频率和潮气量。 引起这些增加的神经机制是有争议的。的 在本申请中提出的实验将确定机械和 这些传入神经的代谢刺激。

DESCRIPTION (Adapted from the applicant's abstract):The overall aim of the experiments proposed in this application is to determine whether dynamic exercise differentially affects the discharge of group III and IV muscle afferents. Exercise will be induced in decerebrate unanesthetized cats by electrical and chemical stimulation of the mesencephalic locomotor region. The effects of various levels of exercise and ischemia on the discharge of the group III and IV muscle afferents will be determined. Particular attention will be paid to afferent's responses to post-exercise circulatory occlusion, a "pure" metaboreflex stimulus. Attention will also be paid to the role played by cyclooxygenase metabolites and bradykinin in stimulating these afferents during dynamic exercise. Finally, the proposed experiments will examine the effect of muscular fatigue on the responses of group III and IV afferents to exercise. These thin fiber afferents have been hypothesized to be responsible for the reflex inhibition of alpha motoneurons during fatiguing muscular contractions in humans. The autonomic and ventilatory response to dynamic exercise are well established and include increases in sympathetic discharge influencing the vasculature, heart rate, contractility, breathing frequency and tidal volume. The neural mechanisms causing these increases are controversial. The experiments proposed in this application will determine the mechanical and metabolic stimuli to these afferents during exercise.