Pintér E, Szolcsányi J
Department of Pharmacology, University Medical School of Pécs, Hungary.
Neuroscience. 1995 Sep;68(2):603-14. doi: 10.1016/0306-4522(95)00104-q.
Electrical stimulation of the distal stump of cut peripheral nerves is a commonly accepted way to evoke neurogenic inflammation. Nevertheless, the modulatory effect of biogenic amines and vasoactive peptides released from efferent fibres can be excluded only if the dorsal roots are stimulated. The present study was focussed to investigate plasma extravasation in the appropriate skin and mucosal areas as well as in the genito-urinary organs in response to antidromic stimulation of the lumbar and sacral dorsal roots of the rat. Plasma extravasation was detected by quantitative measurement of the accumulated Evans Blue tracer in tissue pieces. Two unilateral posterior roots were stimulated simultaneously (20 V, 0.5 ms, 5 Hz, 5 min) in each anaesthetized rat. Intensive blueing response occurred in the following tissues: plantar glabrous skin, L4-L5 (L6); dorsum of the hindpaw and ankle joint, L2-L4; ventral surface of the thigh, L2-L4 (L1); abdominal skin, L1-L4; caudal nipples, L1-L2; root of the tail, S1 orifice of the vagina, S1 (L6); vagina, L2-L3, L5-S1; cervix and corpus uteri, L2-L3, L5-S1; lower two-thirds of the uterine horns, L1-L3; urinary bladder, L1-L3, L6-S1; rectum, L5-S1; scrotum (dorsal surface and lower pole), L6-S1; scrotum (ventral surface), L3-L5. No significant dye accumulation was observed in the muscles, testicles, vas deferens and prostate. Plasma extravasation caused by antidromic activation of the dorsal roots was absent or highly reduced after systemic capsaicin pretreatment of the rats. Neurogenic inflammation evoked by antidromic stimulation of the dorsal roots makes this method suitable for mapping the organs where capsaicin-sensitive sensory nerve endings exert their "efferent functions". This first functional description of segmental innervation of capsaicin-sensitive afferent fibres is in agreement with retrograde tracing studies and immunohistochemical localization of substance P in the dorsal root ganglia and peripheral tissues.
电刺激切断的外周神经远端残端是诱发神经源性炎症的一种普遍认可的方法。然而，只有在刺激背根时，才能排除传出纤维释放的生物胺和血管活性肽的调节作用。本研究旨在调查大鼠腰段和骶段背根逆向刺激后，相应皮肤、黏膜区域以及泌尿生殖器官中的血浆外渗情况。通过定量测量组织块中累积的伊文思蓝示踪剂来检测血浆外渗。在每只麻醉大鼠中同时刺激两条单侧后根（20V，0.5ms，5Hz，5分钟）。在以下组织中出现强烈的蓝染反应：足底无毛皮肤，L4-L5（L6）；后爪背侧和踝关节，L2-L4；大腿腹侧，L2-L4（L1）；腹部皮肤，L1-L4；尾乳头，L1-L2；尾根部，S1；阴道开口，S1（L6）；阴道，L2-L3，L5-S1；子宫颈和子宫体，L2-L3，L5-S1；子宫角下三分之二，L1-L3；膀胱，L1-L3，L6-S1；直肠，L5-S1；阴囊（背侧表面和下极），L6-S1；阴囊（腹侧表面），L3-L5。在肌肉、睾丸、输精管和前列腺中未观察到明显的染料积累。大鼠全身辣椒素预处理后，背根逆向激活引起的血浆外渗消失或显著减少。背根逆向刺激诱发的神经源性炎症使该方法适用于绘制辣椒素敏感感觉神经末梢发挥其“传出功能”的器官。辣椒素敏感传入纤维节段性支配的这一首次功能描述与逆行追踪研究以及背根神经节和外周组织中P物质的免疫组织化学定位一致。
