Spinal hyperexcitability and bladder hyperreflexia during reversible frontal cortical inactivation induced by low-frequency electrical stimulation in the cat.
Spinal hyperexcitability and bladder hyperreflexia during reversible frontal cortical inactivation induced by low-frequency electrical stimulation in the cat.
复制标题
低频电刺激引起猫可逆性额叶皮层失活期间的脊髓过度兴奋和膀胱反射亢进。
DOI：
10.1089/neu.2008.0584
复制
发表时间：
2009
影响因子：
4.2
通讯作者：
McCreery,DouglasB
中科院分区：
文献类型：
--
作者：
Pikov,Victor;McCreery,DouglasB
大多数中风患者逐渐出现脊髓过度兴奋和反射亢进。这些病变的发生是由于脊髓反射的皮层调节减少的结果，脊髓反射主要通过脑干和其他皮层下结构的中继间接介导。脊髓反射的皮质控制在小型动物（例如啮齿类动物）中明显不同，而在一些较大的物种（例如猫）中，其与人类更具相似性。在这项研究中，我们开发了一种新的猫中风模型，在额叶大脑皮层开始低频电刺激后约 1 小时，出现皮质神经元活动的可控和可逆抑制，额叶皮层电信号的 α 频段（7-14Hz）大幅增加证明了这一点。使用优化的刺激参数（频率为 1-2Hz，幅度为 10mA，施加 30 分钟）诱导可逆性皮质失活后 3 小时或更长时间，出现膀胱反射亢进。膀胱反射亢进持续至少8小时，并在24小时内消失。在脊髓的 S2 水平，介导排尿和其他骨盆反射的神经回路所在，我们记录到与反射亢进相关的神经元活动的增加。低频刺激引起的可逆性皮质失活模型具有高度可重复性，并且可以通过实验条件下的动物内比较来评估脊髓过度兴奋和反射亢进，这对于检查中风或脑外伤后脊髓反射亢进的机制以及开发针对这些情况的更有效的治疗方法具有重要价值。
Spinal hyperexcitability and hyperreflexia gradually develop in the majority of stroke patients. These pathologies develop as a result of reduced cortical modulation of spinal reflexes, mediated largely indirectly via relays in the brainstem and other subcortical structures. Cortical control of spinal reflexes is markedly different in small animals, such as rodents, while in some larger species, such as cats, it is more comparable to that in humans. In this study, we developed a novel model of stroke in the cat, with controllable and reversible inhibition of cortical neuronal activity appearing approximately 1 h after initiation of low-frequency electrical stimulation in the frontal cerebral cortex, evidenced by a large increase in the alpha frequency band (7–14 Hz) of the frontal electrocorticographic signal. Hyperreflexia of the urinary bladder developed 3 h or more after induction of reversible cortical inactivation with optimized stimulation parameters (frequency of 1–2 Hz, amplitude of 10 mA, applied for 30 min). The bladder hyperreflexia persisted for at least 8 h, and disappeared within 24 h. At the S2level of the spinal cord, where neural circuits mediating micturition and other pelvic reflexes reside, we have recorded an increase in neuronal activity correlated with the development of hyperreflexia. The low-frequency stimulation-induced reversible cortical inactivation model of stroke is highly reproducible and allows evaluation of spinal hyperexcitability and hyperreflexia using within-animal comparisons across experimental conditions, which can be of great value in examination of mechanisms of spinal hyperreflexia following stroke or brain trauma, and for developing more effective treatments for these conditions.