Avelino A, Cruz F, Coimbra A
Institute of Histology and Embryology, Faculty of Medicine of Porto, IBMC of University of Porto, Portugal.
J Urol. 1998 Feb;159(2):567-70. doi: 10.1016/s0022-5347(01)63985-5.
The effects of the local anesthetic lidocaine on the noxious excitation and subsequent desensitization of bladder sensory fibers, produced by intravesical capsaicin, were evaluated through c-fos activation in the spinal cord.
Noxious excitation was demonstrated by counting Fos-immunoreactive (IR) cells occurring in the rat spinal cord 2 hours after intravesical administration of 1 mM. capsaicin, preceded or not by 2% lidocaine. Desensitization was studied by comparing the number of Fos-IR cells induced by 1% acetic acid in rats treated 24 hours before with 1 mM. intravesical capsaicin preceded or not by 2% lidocaine.
Lidocaine instilled previously markedly reduced the number of Fos-IR spinal cells responding to capsaicin-induced bladder afferent excitation. Numbers of Fos-IR cells induced by acetic acid instillation in bladders desensitized by capsaicin administrated 24 hours before were not changed by lidocaine application prior to capsaicin.
These findings suggest that local anesthetic pretreatment of the bladder with lidocaine reduces the capsaicin-induced noxious excitation of the sensory fibers without decreasing their subsequent desensitization.
通过脊髓中c-fos激活来评估局部麻醉药利多卡因对膀胱感觉纤维由膀胱内注入辣椒素所产生的伤害性兴奋及随后脱敏的影响。
在膀胱内注入1 mM辣椒素（有无2%利多卡因预处理）2小时后，通过计数大鼠脊髓中出现的Fos免疫反应性（IR）细胞来证明伤害性兴奋。通过比较在预先用1 mM膀胱内辣椒素（有无2%利多卡因预处理）处理24小时的大鼠中，由1%乙酸诱导的Fos-IR细胞数量来研究脱敏情况。
预先注入利多卡因显著减少了对辣椒素诱导的膀胱传入兴奋产生反应的Fos-IR脊髓细胞数量。在24小时前用辣椒素脱敏的膀胱中，由乙酸注入诱导的Fos-IR细胞数量，在辣椒素之前应用利多卡因并未改变。
这些发现表明，用利多卡因对膀胱进行局部麻醉预处理可降低辣椒素诱导的感觉纤维伤害性兴奋，而不会降低其随后的脱敏作用。
