Neuroprotection via maintenance or increase of antioxidants and neurotrophic factors in ischemic gerbil hippocampus treated with tanshinone I / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Danshen (Radix Salvia miltiorrhizae) has been used as a traditional medicine in Asia for treatment of various microcirculatory disturbance related diseases. Tanshinones are mainly hydrophobic active components, which have been isolated from Danshen and show various biological functions. In this study, we observed the neuroprotective effect of tanshinone I (TsI) against ischemic damage in the gerbil hippocampal CA1 region (CA1) after transient cerebral ischemia and examined its neuroprotective mechanism.</p><p><b>METHODS</b>The gerbils were divided into vehicle-treated-sham-group, vehicle-treated-ischemia-group, TsI-treated-sham-group, and TsI-treated-ischemia-group. TsI was administrated intraperitoneally three times (once a day for three days) before ischemia-reperfusion. The neuroprotective effect of TsI was examined using H&E staining, neuronal nuclei (NeuN) immunohistochemistry and Fluoro-Jade B staining. To investigate the neuroprotective mechanism of TsI after ischemia-reperfusion, immunohistochemical (IHC) and Western blotting analyses for Cu, Zn-superoxide dismutase (SOD1), Mn-superoxide dismutase (SOD2), brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-I (IGF-I) were performed.</p><p><b>RESULTS</b>Treatment with TsI protected pyramidal neurons from ischemia-induced neuronal death in the CA1 after ischemia-reperfusion. In addition, treatment with TsI maintained the levels of SOD1 and SOD2 as determined by IHC and Western blotting in the CA1 after ischemia-reperfusion compared with the vehicle-ischemia-group. In addition, treatment with TsI increased the levels of BDNF and IGF-I determined by IHC and Western blotting in the TsI-treated-sham-group compared with the vehicle-treated-sham-group, and their levels were maintained in the stratum pyramidale of the ischemic CA1 in the TsI-treated-ischemia-group.</p><p><b>CONCLUSION</b>Treatment with TsI protects pyramidal neurons of the CA1 from ischemic damage induced by transient cerebral ischemia via the maintenance of antioxidants and the increase of neurotrophic factors.</p>

Neuroprotective effects of tanshinone I from Danshen extract in a mouse model of hypoxia-ischemia / 대한해부학회지

Hypoxia-ischemia leads to serious neuronal damage in some brain regions and is a strong risk factor for stroke. The aim of this study was to investigate the neuroprotective effect of tanshinone I (TsI) derived from Danshen (Radix Salvia miltiorrhiza root extract) against neuronal damage using a mouse model of cerebral hypoxia-ischemia. Brain infarction and neuronal damage were examined using 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin and eosin histochemistry, and Fluoro-Jade B histofluorescence. Pre-treatment with TsI (10 mg/kg) was associated with a significant reduction in infarct volume 1 day after hypoxia-ischemia was induced. In addition, TsI protected against hypoxia-ischemia-induced neuronal death in the ipsilateral region. Our present findings suggest that TsI has strong potential for neuroprotection against hypoxic-ischemic damage. These results may be used in research into new anti-stroke medications.

Differential effects of treadmill exercise on cyclooxygenase-2 in the rat hippocampus at early and chronic stages of diabetes / 한국실험동물학회지

Cyclooxygenase-2 (COX-2) is believed to be a multifunctional neural modulator that affects synaptic plasticity in the hippocampus. In the present study, we investigated the differential effects of treadmill exercise on COX-2 immunoreactivity in the dentate gyrus in early and chronic diabetic stages in Zucker diabetic fatty (ZDF) rats and lean control (ZLC) rats. To this end, ZLC and ZDF rats at 6 or 23 weeks of age were put on a treadmill with or without running for 1 h/day for 5 consecutive days at 16-22 m/min for 5 weeks or 12-16 m/min for 7 weeks, respectively. Treadmill exercise in prediabetic and chronic diabetic rats significantly reduced blood glucose levels. In particular, exercise in the prediabetic rat blocked the onset of diabetes. COX-2 immunoreactivity was mainly detected in the granule cell layer of the dentate gyrus and stratum pyramidale of the CA3 region in all groups. COX-2 immunoreactivity was significantly increased in these regions of ZLC and ZDF rats after treadmill exercise in the early diabetic stage. However, COX-2 immunoreactivity was not changed in these regions in ZDF rats after treadmill exercise in the chronic stage. These results suggest that treadmill exercise in diabetic animals in the chronic stage has limited ability to cause plasticity in the dentate gyrus.

Effects of repeated restraint stress on platelet endothelial cell adhesion molecule-1 immunoreactivity and protein levels in the gerbil hippocampus after transient cerebral ischemia / 대한해부학회지

Stress has long been known to be a causative factor of various disease states. In this study, we investigated the effects of repeated restraint stress on platelet endothelial cell adhesion molecule-1 (PECAM-1), a very important mediator in inflammation, immunoreactivity and protein levels as well as neuronal damage, in the gerbil hippocampus after 5 minutes of transient cerebral ischemia. Transient ischemia-induced neuronal death was shown in CA1 pyramidal cells 4 days after ischemia/reperfusion. However, repeated restraint stress protected neuronal death induced by ischemic damage. In the ischemia-group, PECAM-1 immunoreactivity and its protein levels were significantly increased in all the hippocampal subregions 4 days after ischemia/reperfusion. However, PECAM-1 immunoreactivity and its protein levels did not change significantly in the hippocampus of the stress-ischemia-group compared to the sham-groups. These results indicate that repeated restraint stress protects neuronal damage induced by transient cerebral ischemia, and this may be associated with maintenance of PECAM-1levels.

Doublecortin-immunoreactive Neuroblasts in Each Layer of the Main Olfactory Bulb After Transient Cerebral Ischemia in Gerbils / 한국실험동물학회지

Neurogenesis in the adult brain occurs continuously throughout life. The main olfactory bulb (MOB) is the first central relay of the olfactory system. We examined proliferation of newly generated cells in each layer of the gerbil MOB after 5 min of transient cerebral ischemia using doublecortin (DCX), a marker of neuronal progenitors. Many DCX immunoreactive neuroblasts were found in the all layers of the MOBs of control and ischemia groups. Ten to 15 days after ischemia/reperfusion, no difference in numbers of DCX immunoreactive neuroblasts was found in the MOB. Thirty days after ischemia/reperfusion, significant increase of DCX immunoreactive cells was observed in all layers of ischemic MOB. This result indicates that neuroblasts increase in the MOB from 30 days after transient cerebral ischemia in gerbils.

The long-term clinical effect of cutting ballon angioplasty for coronary in-stent restenosis / 대한내과학회지

BACKGROUND: Coronary stent implantation reduced the restenosis rate after percutaneous coronary intervention (PCI) but, still coronary in-stent restenosis (ISR) remains the major problem after PCI. Cutting balloon angioplasty is one of the method for ISR treatment. The purpose of this study is prospectively comparing the effect of cutting balloon angioplasty (CBA) with plain old balloon angioplasty (POBA) for the ISR. METHODS: A total of 50 patients with ISR, who underwent PCI (randomized CBA or POBA for ISR) from January to December 2001 at Chonnam National University Hospital, were divided into two groups: Group I (n=25: 58.4+/-7.9 years, male 88%) with CBA and Group II (n=25: 58.1+/-8.7 years, male 92%) with POBA. The early luminal gain, late luminal loss, major adverse cardiac event and angiographic restenosis rate were compared. RESULTS: There were no differences in baseline clinical characteristics of sex, age, ejection fraction, cardiac enzyme, risk factors of atherosclerosis, number of coronary artery lesions, and type of ISR between the groups. The minimal luminal diameters of before and after PCI were 0.83+/-0.34 mm, 2.10+/-0.55 mm in group I and 0.93+/-0.58 mm, 2.08+/-0.79 mm in group II. There were no differences in early luminal gain. All patients underwent follow-up coronary angiogram and the restenosis rate was 32% (8/25) in group I and 28% (7/25) in group II, and late luminal loss were 0.60+/-0.40 mm in group I and 0.65+/-0.61 in group II (p=NS). The major adverse cardiac events during 6-month follow-up developed in 3 cases of group I and 4 cases of group II (p=NS). CONCLUSION: There were no differences in early and long-term clinical effects after CBA and POBA for the treatment of ISR.

Initial and late results of Freedom coronary stent

OBJECTIVES: Initial and late results after implantation of Freedom stents, a balloon expandable stainless steel coil stents were evaluated. METHODS: From Jun. 1996 to Nov. 1997, we implanted 123 Freedom stents in 122 lesions in 117 patients and performed follow-up coronary angiograms at 7.0 3.6 months after stents placement. Clinical courses after stenting and follow-up coronary angiographic findings were evaluated. Comparison of clinical, angiographic, and procedural factors according to the presence or absence of restenosis was performed. RESULTS: In 117 patients who underwent stents implantation, major complications were not observed. Follow-up coronary angiograms were performed in 47 stents in 41 patients (35+ACU-). Among 47 stents, angiographic significant restenosis (percent diameter stenosis +AD4- 50+ACU-) was observed in 13 (28+ACU-). Mean age in 41 patients was 59 9 years, with 27 male patients (66+ACU-). Indications for stents implantation were de novo lesions in 18 (38+ACU-), suboptimal results after PTCA in 18 (38+ACU-), bail-out lesions in 4 (9+ACU-) and restenotic lesions in 7 (15+ACU-). Lesion types by AHA/ACC classification were A in 1 (1+ACU-), B1 in 10 (21+ACU-), B2 in 17 (36+ACU-), and C in 19 (40+ACU-). Average lesion length was 13.7 9.0 mm, stent diameter 3.0 0.3 mm, and stent length 24.6 9.0 mm. There were no significant differences of the clinical, angiographic, and procedural characteristics according to the presence or absence of restenosis. CONCLUSION: Freedom coronary stents implantation is safely performed in various morphology of coronary lesions and no significant predictive factors on restenosis in follow-up coronary angiogram were observed.

Protective Action of Purinergic and Cholinergic Agonists on the Ischemic Myocardium in the Rat

BACKGROUND: Purinergic and cholinergic agonists elicit negative-inotropic and chronotropic effects, anticip-ating their protective action from the damage of overloaded myocardium. However, the actions of the agents during the ischemic insults are not yet clearly informed. The aim of this study was to investigate the role of the purinergic and cholinergic agonists on the simulated ischemic myocardium of the rat atrial fiber preparations. METHOD: Various action potential parameters (maximum diastolic potential MDP;action potential amplitude APA;velocity of phase 0 depolarization dV/dtmax;action potential duration APD90) were measured and compared in electrically paced, normal (NPSS) and modified physiological salt solution (MPSS) superfused rat atrial fibers in vitro, using conventional 3M-KCl microelectrode technique. Ischemia-simulated modified physiologic solutions were prepared by changing the solution's composition. RESULTS: Hypoxic-and/or hyperkalemic-MPSS decreased all the action potential (AP) variables. However, no significant changes of the AP variables were developed by the acidic-or glucose-free MPSS. Adenosine (Ado) and cyclopentyladenosine (CPA) only decreased the APD90 in a dose-dependent manner. Acetylcholine (Ach) and carbachol (Cch) hyperpolarized the MDP, increased the dV/dtmax with certain doses, and decreased the APD90 dose-depen-dently. The potency for APD90-decrease was greater in order, CPA>Cch>Ach>Ado. Ado and CPA did not affect the hypoxic, hypokalemic MPSS-induced dV/dtmax-decrease. On the other hand, Ach and Cch sig-nificantly inhibited the dV/dtmax-decrease by the hypoxic hypokalemic-MPSS. Ado, CPA, Ach and Cch sig-nificantly augmented the hypoxic, hypokalemic MPSS-induced APD90-decrease. The inhibition by the Ach and Cch on the MPSS-induced dV/dtmax-decrease was not affected by DPCPX, but atropine significantly attenuated the inhibition by the cholinergic agonists. DPCPX inhibited the augmentation by the Ado and CPA on the MPSS induced APD90-decrease, and atropine inhibited the effect of the cholinergic agonists. CONCLUSION: Both purinergic and cholinergic agonists not only shorten the AP duration by themselves but also enhance the AP-shortening effect elicited by the ischemia, and therefore, it is inferred that both agonists prevent further tissue damage from the ischemic insults.

Earlyclicical result of coronary artery bypass surgery for ischemic heart disease / 대한흉부외과학회지

No abstract available.

Left ventricular hypertrophy in end-stage renal disease / 대한신장학회잡지

No abstract available.

Internal mammary artery grafting without intraluminal dilatation / 대한흉부외과학회지

No abstract available.

The Effect of Diphenylhydantoin on the Action of Ouabain

The effect of diphenylhydantoin on LD 50 of ouabain was investigated in frogs, using "one hour frog method". LD50 of ouabain in control group was 1.90 microg/10g. A dose of 100 microg/10g diphenylhydantion did not affect the systemic manifestations of the frogs, but increase the LD50 of ouabain to 2.60 microg/10g. The difference of LD50 of ouabain and potency ratio between control group and diphenylhydantoin-treated group was statistically significant.