Role of the mesencephalic and pontine reticular formation upon experimentally induced tonic convulsion

采用猫或大鼠一侧中脑网状结构(MRF)或桥脑网状结构(PRF)微量注射海人酸(KA)所致的全身性癫痫模型，研究癫痫的传播模式。对猫进行立体定向手术，将KA微量注射管植入MRF或PRF，术后1周在自由活动状态下进行KA注射。在EEG上，最初在MRF或PRF的注射部位诱发局灶性癫痫状态，然后发展为癫痫发作，并诱导全身性强直发作。MRF发作的临床表现为全身性强直发作，继之以短时间阵挛发作，而PRF发作则为全身性强直发作。在大鼠的MRF或PRF内立体定向植入套管，术后一周用~(14)C-脱氧葡萄糖、~(131)I-碘马西尼或~(14)C-安替比林进行放射自显影。研究局部葡萄糖利用方式(1CGU)、苯二氮卓类受体分布或局部脑血流量(1CBF)。结果表明，皮质分离通路在MRF发作的泛化中起重要作用，内侧前脑束在PRF发作的泛化中起重要作用。

The mode of seizure propagation was studied using generalized seizure models induced by a microinjection of kainic acid (KA) into unilateral mesencephalic reticular formation (MRF) or pontine reticular formation (PRF) of unrestrained cats or rats. Stereotaxic operation was performed in cats and a cannula for KA microinjection was implanted into MRF or PRF.One week after the surgery, KA injection was performed in freely moving condition. On EEG,a focal seizure status was initially induced at the injected site of the MRF or PRF.These seizure developed and generalized tonic seizures were induced. Clinical manifestation of MRF seizure was characterized by generalized tonic seizures followed by short clonic seizures, while that of PRF seizure was generalized tonic seizures.In rats, a cannula was implanted stereotaxically into MRF or PRF.One week after the surgery, autoradiography was performed using 14C-deoxyglucose, 131I-iomazenil or 14C-iodoantipyrine. The mode of local glucose utilization (1CGU), distribution of benzodiazepine receptors or local cerebral blood flow (1CBF) were studied. The results demonstrated that corticofugal pathway plays an important role in the generalization of MRF seizure and medial forebrain bundle plays an important role in the generalization of the PRF seizure.