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To understand the characteristics of posterior circulation ischemic stroke (PCS) in the Korean population better, we retrospectively reviewed the data from the Hallym Stroke Registry (HSR). We analyzed the demographic features, risk factors, stroke subtypes, lesion distributions and clinical outcomes of 591 consecutive patients with PCS, enrolled in HSR between January 1996 and July 2002. PCS was 39.8% of all ischemic strokes. Mean age of PCS patients was 63.4 years and 55.7% were men. Hypertension was the most common risk factor (69.9%). However, potential cardioembolic sources were found only in 11.0%. The most frequent stroke subtype was large artery disease (50.0%), followed by small vessel disease (33.8%). Only 5.2% of patients were classified as affected with cardioembolism. The most common location of infarcts was in the middle territory (36.5%), followed by distal (28.1%), proximal (19.0%), and multiple territories (16.4%). The hospital mortality rate (4.1%) and discharge outcome of PCS were comparable with those of the anterior circulation stroke (ACS). In conclusion, the etiology and lesion topography of PCS in the Korean population appeared to be different from those of the Caucasians.

To elucidate the pharmacological properties of perampanel [2-(2-oxo-1-phenyl-5-pyridin-2-yl-1,2-dihydropyridin-3-yl)benzonitrile, a novel non-competitive antagonist of AMPA receptor], we investigated its effects on the up-stream regulatory pathways of GluA1 phosphorylation including protein kinase C (PKC), Ca 2+ -calmodulin-dependent protein kinase II (CAMKII), protein kinase A (PKA), extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), protein phosphatase (PP) 1, PP2A, and PP2B in normal and pilocarpine-induced epileptic rat model using Western blot analysis. In normal animals, perampanel affected GluA1 expression/phosphorylation, PKC, CAMKII, PKA, ERK1/2, JNK, and PPs activities. In epileptic rats, perampanel effectively inhibited spontaneous seizure activities. Perampanel enhanced phospho (p)-GluA1-S831 and -S845 ratios (phosphoprotein/total protein), while it reduced GluA1 expression. Perampanel also increased pCAMKII and pPKA ratios, which phosphorylate GluA1-S831 and -S845 site, respectively. Perampanel elevated pJNK and pPP2B ratios, which phosphorylates and dephosphorylates both GluA1-S831 and -S845 sits. Perampanel also increased pERK1/2 ratio in epileptic animals, while U0126 (an ERK1/2 inhibitor) did not affect pGluA1 ratios. Perampanel did not influence PKC, PP1, and PP2A expression levels and their phosphorylation ratios. In addition, perampanel did not have a detrimental impact on cognitive abilities of epileptic and normal rats in Morris water maze test. These findings suggest that perampanel may regulate AMPA receptor functionality via not only blockade of AMPA receptor but also the regulations of multiple molecules (CAMKII, PKA, JNK, and pPP2B)-mediated GluA1 phosphorylations without negative effects on cognition, although the effects of perampanel on PKC, PP1, and PP2A activities were different between normal and epileptic rats.

Objectives:In Korea, stroke ranks as one of the leading causes of death along with cancer and ischemic heart disease. The purpose of this study was to better understand clinical characteristics, risk factors and subtypes of acute stroke among Korean people. Method: 1,654 acute stroke patients within 7 days of onset were consecutively enrolled in the Hallym Stroke Registry (HSR). The study was a prospective hospital-based registry aided with a web-based, computerized data bank system. The project began in January 1996 and the data obtained until September 2002 were analyzed. The analysis was basically carried out regarding demographic features, risk factors, time elapsed before coming to the hospitals after the symptom onset, duration of hospitalization, and 30-day mortality rate. Results: 1,567 patients had ischemic stroke and 87 patients had hemorrhagic stroke. The mean age of the patients was 63.6 ± 11.8 years, and 815 patients (56.8%) were men. The estimated time interval between stroke onset and hospital visit was 1.3 days on average and the mean duration of hospital stay was 12.1 days. Only a small fraction (12%) of patients reached the hospital within 3 h after the symptom onset. As for the risk factors, hypertension topped for both ischemic and hemorrhagic strokes followed by smoking and prior history of stroke, diabetes, hyperlipidemia and cardioembolism. With respect to subtype classification of ischemic stroke, large-artery atherosclerosis was most frequent (42.0%), followed by small-vessel occlusion (31.0%), cardioembolism (8.7%), other determined etiology (1.9%), and undetermined etiology (16.4%). The 30-day mortality rate was 7.2%. Conclusion: In the HSR, demographic features were essentially comparable with other major registries. However, the data analysis varies from registry to registry. This may in part be due to a different study design, racial-ethnic differences and patient selection methods.