Foreman R D, Blair R W, Holmes H R, Armour J A
Department of Physiology, Health Sciences Center, University of Oklahoma, Oklahoma City, Oklahoma 73190, USA.
Am J Physiol. 1999 Apr;276(4):R979-89. doi: 10.1152/ajpregu.1999.276.4.R979.
The mechanosensory activity generated by ventricular epicardial sensory neurites associated with afferent axons in thoracic sympathetic nerves was correlated with sensory field deformation (long axis, short axis, and transmural dimension changes), regional intramyocardial pressure, and ventricular chamber pressure in anesthetized dogs. Ventricular mechanosensory neurites generated activity that correlated best with strain developed along either the long or short axis of their epicardial sensory fields in most instances. Activity did not correlate normally to local wall thickness or to regional wall or chamber pressure development in most cases. During premature ventricular contractions, the activity generated by these sensory neurites correlated best with maximum strain developed along at least one sensory field epicardial vector. Identified sensory neurites were also activated by local application of the chemical bradykinin (10 microM) or by local ischemia. These data indicate that the activity generated by most ischemia-sensitive ventricular epicardial sensory neurites associated with afferent axons in sympathetic nerves is dependent on not only their local chemical milieu but on local mechanical deformation along at least one epicardial vector of their sensory fields.
在麻醉犬中，与胸段交感神经传入轴突相关的心室心外膜感觉神经突产生的机械感觉活动，与感觉野变形（长轴、短轴和透壁维度变化）、局部心肌内压力和心室腔压力相关。在大多数情况下，心室机械感觉神经突产生的活动与沿其心外膜感觉野长轴或短轴产生的应变最相关。在大多数情况下，活动与局部壁厚或局部壁或腔压力变化通常不相关。在室性早搏期间，这些感觉神经突产生的活动与沿至少一个感觉野心外膜向量产生的最大应变最相关。通过局部应用化学物质缓激肽（10微摩尔）或局部缺血也可激活已识别的感觉神经突。这些数据表明，与交感神经传入轴突相关的大多数对缺血敏感的心室心外膜感觉神经突产生的活动不仅取决于其局部化学环境，还取决于沿其感觉野至少一个心外膜向量的局部机械变形。
