• The Korean Journal of Physiology and Pharmacology
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• v.5 no.3
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• pp.205-212
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• 2001

It has been proposed that nitirc oxide is involved in the pathogenesis of cerebral ischemia-reperfusion. Because superoxide production is also enhanced during reperfusion, the cytotoxic oxidant peroxynitrite could be formed, but it is not known if this occurs following global forebrain ischemia-reperfusion. We examined whether peroxynitrite generation is increased in the vulnerable regions after forebrain ischemia-reperfusion. Transient forebrain ischemia was produced in the conscious rat by four-vessel occlusion. Rats were subjected to 10 or 15 min of forebrain ischemia. Immunohistochemical method was used to detect 3-nitrotyrosine, a marker of peroxynitrite production. 3-Nitrotyrosine immunoreactivity was enhanced in the hippocampal CA1 area 3 days after reperfusion. Furthermore, in rats subjected to ischemia for 15 min, this change was also observed in the lateral striatal region and the lateral septal nucleus $2{\sim}3$ days after reperfusion. The cresyl violet staining of adjacent sections showed that neuronal cell death was induced in parallel with the nitrotyrosine immunoreactivity in the hippocampal CA1 area and the lateral striatal region. Our findings suggest that oxygen free radical accumulation and consequent peroxynitrite production play a role in neuronal death caused by cerebral ischemia-reperfusion.

• Applied Microscopy
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• v.35 no.3
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• pp.135-152
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• 2005

Prefrontal cortex is a psychological and metaphysical cortex, which deals with feeling, memory, planning, attention, personality, etc. And it also integrates above-mentioned events with motor control and locomotor activities. Prefrontal cortex works as a highest CNS center, since the above mentioned functions are very important for one's successful life, and further more they are upgraded every moments through memory and learning. Many of these highest functions are supposed to be generated via forebrain basal nuclei (caudate nucleus, fundus striati nucleus, accumbens septi nucleus, septal nucleus, etc.). In this experiment, prefrontal efferent terminals within basal forebrain nuclei were ultrastructurally studied. Spraque Dawley rats, weighing $250{\sim}300g$ each, were anesthetized and their heads were fixed on the stereotaxic apparatus (experimental model, David Kopf Co.). Rats were incised their scalp, perforated a 3mm-wide hole on the right side of skull at the 11mm anterior point from the frontal O point (Ref. 13, Fig. 1), suctioned out the prefrontal cortex including cortex of the frontal pole, with suction instrument. Two days following the operations, small tissue blocks of basal forebrain nuclei were punched out, fixed in 1% glutaraldehyde-1% paraformaldehyde solution followed by 2% osmium tetroxide solutions. Ultrathin sections were stained with 1% borax-toluidin blue solution, and the stained sections were obserbed with an electron microscope. Degenerating axon terminals were found within all the basal forbrain nuclei. Numbers of degenerated terminals were largest in the caudate nucleus, next in order, in the fundus striati nucleus, in the accumbens septi nucleus, and the least in the septal nucleus. Only axospinous terminals were degenerated within the caudate nucleus and the fundus striati nucleus, and they showed the characters of striatal motor control system. Axodendritic and axospinous terminals were degenerated within the accumbens septi nucleus and the lateral septal nucleus, and they showed the characters of visceral limbic system. Prefrontal role in integrating the limbic system with the striatal system, en route basal forebrain nuclei, was discussed.

• Korean Journal of Veterinary Research
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• v.42 no.3
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• pp.429-436
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• 2002

Hydrocepbalus may be an acquired or a congenital condition. We have studied the macroscopic and microscopic changes in the hydrocephalus of an inbred Sprague-Dawley rat at postnatal week 8. The animal suspected with the hydrocephalus showed clinical syndromes such as depression, severe ataxia, eye abnormalities, dome-shaped head, and persistent fontanelle. With the postmortem examination, the suspected animal was clearly revealed as a severe internal hydrocephalus. In this animal, severe ventriculomegaly was limited to the third and lateral ventricles, and cortical thining was most apparent in the parieto-occipital region. With the routine histological examination, brain tissue showed aqueductal obstruction, thinning of the cerebral cortex, severe ependymal damage, subependymal edema, damage of choroid plexus of fourth ventricle, enlarged cortical vessels, and expanded ventricles. Aqueductal obstruction was observed with the appearance of simple stenosis at the level of rostral colliculus. Subsequently, the other structures of brain such as septal nucleus, caudate nucleus, and hippocampus etc. were abnormally reconstructed by hydrocephalus. This study suggests that the hydrocephalus can be taken place by primary aqueductal obstruction and this type of hydrocephalus is classified as uncommunicating type. Though the mechanism of aqueductal obstruction is not clear, the morphological studies of this case may be helpful for the further study of hydrocephalus.

• The Journal of Korean Medicine
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• v.24 no.3
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• pp.51-64
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• 2003

Objective : This study investigated the alteration of neural activity and effect of Yanggyuksanhwa-tang (Lianggesanhuo-tang) on cerebral ischemia of rats. Methods : Considering age-related impact on cerebral ischemia, aged rats (18 months old) were used for this study. Ischemic damage was induced by the transient occlusion of bilateral common carotid arteries (BCAO) with hypotension. Yanggyuksanhwa-tang (Lianggesanhuo-tang) was administered twice a day orally. Then alterations of neural activities in the brain of aged BCAO rats were measured by the [$^{14}C$]2-deoxyglucose autoradiography method. Results : The BCAO in aged rats led to significant decrease of neural activity in the whole brain. Treatment with Yanggyuksanhwa-tang (Lianggesanhuo-tang) significantly attenuated the decrease of neural activity in the whole brain following BCAO ischemia. Treatment significantly attenuated the decrease of neural activity in the CA1, CA2, CA3, dentate gyrus of the hippocampus, activated barrel, barrel cortex, somatosensory cortex, cingulate cortex, caudate putamen, and medial septal nucleus following BCAO in aged rats. Treatment with Yanggyuksanhwa-tang (Lianggesanhuo-tang) also significantly attenuated the decrease of neural activity in the anteroventral thalamic nucleus, ventral anterior thalamic nucleus, arcuate nucleus, posterior hypothalamic area, medial mammillary nucleus, lateral periaqueductal gray, dorsal raphe nucleus, interpeduncular nucleus, median raphe nucleus, and medial pontine nucleus. Conclusion : It can be suggested that Yanggyuksanhwa-tang (Lianggesanhuo-tang) has a neuroprotecuve effect on cerebral ischemia through the control of glucose metabolic rate and cerebral blood flow.