• Journal of Pharmaceutical Investigation
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• 제25권3호spc1호
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• pp.7-20
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• 1995

Taurine, a ${\beta}-amino$ acid, plays an important role as a neuromodulator and is necessary for the normal development of the brain. Since de novo synthesis of taurine in the brain is minimal and in vivo studies suggest that taurine dose not cross the blood-brain barrier, we examined whether the choroid plexus, the blood-cerebrospinal fluid (CSF) barrier, plays a role in taurine transport in the central nervous system. The uptake of $[^3H]-taurine$ into ATP depleted choroid plexus from rabbit was substantially greater in the presence of an inwardly directed $Na^+$ gradient taurine accumulation was negligible. A transient in side-negative potential gradient enhanced the $Na^+-driven$ uptake of taurine into the tissue slices, suggesting that the transport process is electrogenic, $Na^+-driven$ taurine uptake was saturable with an estimated $V_{max}$ of $111\;{\pm}\;20.2\;nmole/g/15\;min$ and a $K_M\;of\;99.8{\pm}29.9\;{\mu}M$. The estimated coupling ratio of $Na^+$ and taurine was $1.80\;{\pm}\;0.122.$ $Na^+-dependent$ taurine uptake was significantly inhibited by ${\beta}-amino$ acids, but not by ${\alpha}-amino$ acids, indicating that the transporter is selective for ${\beta}-amino$ acids. Since it is known that the physiological concentration of taurine in the CSF is lower than that in the plasma, the active transport system we characterized may face the brush border (i.e., CSF facing) side of the choroid plexus and actively transport taurine out of the CSF. Therefore, we examined in vivo elimination of taurine from the CSF in the rat to determine whether elimination kinetics of taurine from the CSF is consistent with the in vitro study. Using a stereotaxic device, cannulaes were placed into the lateral ventricle and the cisterna magna of the rat. Radio-labelled taurine and inulin (a marker of CSF flow) were injected into the lateral ventricle, and the concentrations of the labelled compounds in the CSF were monitored for upto 3 hrs in the cisterna magna. The apparent clearance of taurine from CSF was greater than the estimated CSF flow (p<0.005) indicating that there is a clearance process in addition to the CSF flow. Taurine distribution into the choroid plexus was at least 10 fold higher than that found in other brain areas (e. g., cerebellum, olfactory bulb and cortex). When unlabelled taurine was co-administered with radio-labelled taurine, the apparent clearance of taurine was reduced (p<0.0l), suggesting a saturable disposition of taurine from CSF. Distribution of taurine into the choroid plexus, cerebellum, olfactory bulb and cortex was similarly diminished, indicating that the saturable uptake of taurine into these tissues is responsible for the non-linear disposition. A pharmacokinetic model involving first order elimination and saturable distribution described these data adequately. The Michaelis-Menten rate constant estimated from in vivo elimination study is similar to that obtained in the in vitro uptake experiment. Collectively, our results demonstrate that taurine is transported in the choroid plexus via a $Na^+-dependent,saturable$ and apparently ${\beta}-amino$ acid selective mechanism. This process may be functionally relevant to taurine homeostasis in the brain.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 제4회 추계심포지움
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• pp.99-113
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• 1996

Taurine, a ${\beta}$-amino acid, plays an important role as a neuromodulator and is necessary for the normal development of the brain. Since de novo synthesis of taurine in the brain is minimal and in vivo studies suggest that taurine does not cross the blood-brain barrier, the blood-cerebrospinal fluid (CSF) barrier is likely to play a role in taurine transport between the central nervous system and the systemic circulation. Therefore, we examined in vivo elimination of taurine from the CSF in the rat to characterize in vivo kinetics of elimination for taurine from the CSF is consistent with the in vitro study. Using a stereotaxic device, cannulaes were placed into the lateral ventricle and the cisterna magna of the rat. Radio-labelled taurine and inulin (a marker of CSF flow) were injected into the lateral ventricle, and the concentrations of the labelled compounds in the CSF were monitored for up to 3 hrs in the cisterna magna. The apparent clearance of taurine from CSF was greater than the estimated CSF flow (p<0.005), indicating that there is a clearance process in addition to the CSF flow. Taurine distribution into the choroid plexus was at least 10 fold higher than that found in other brain areas (e.g., cerebellum, olfactory bulb and cortex). When unlabelled taurine was co-administered with radio-labelled taurine, the apparent clearance of the labeled taurine was reduced (p<0.01), suggesting a saturable disposition of taurine from CSF. Distribution of taurine into the choroid plexus, cerebellum, olfactory bulb and cortex was similarly diminished, indicating that the saturable uptake of taurine into these tissues is responsible for the non-linear disposition. A pharmacokinetic model involving first order elimination and saturable distribution described these data adequately. The Michaelis-Menten rate constant estimated from in vivo elimination study is similar to that obtained in the in vitro uptake experiment Collectively, our results demonstrate that taurine is transported in the choroid plexus via a taurine is cleared from the CSF via a saturable process. This process may be functionally relevant to taurine homeostasis in the brain.

• Journal of Korean Neurosurgical Society
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• 제58권1호
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• pp.1-8
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• 2015

Treatment of Leptomeningeal carcinomatosis (LMC) from solid cancers has not advanced noticeably since the introduction of intra-cerebrospinal fluid (CSF) chemotherapy in the 1970's. The marginal survival benefit and difficulty of intrathecal chemotherapy injection has hindered its wide spread use. Even after the introduction of intraventricular chemotherapy with Ommaya reservoir, frequent development of CSF flow disturbance, manifested as increased intracranial pressure (ICP), made injected drug to be distributed unevenly and thus, the therapy became ineffective. Systemic chemotherapy for LMC has been limited as effective CSF concentration can hardly be achieved except high dose methotrexate (MTX) intravenous administration. However, the introduction of small molecular weight target inhibitors for primary cancer treatment has changed the old concept of 'blood-brain barrier' as the ultimate barrier to systemically administered drugs. Conventional oral administration achieves an effective concentration at the nanomolar level. Furthermore, many studies report that a combined treatment of target inhibitor and intra-CSF chemotherapy significantly prolongs patient survival. Ventriculolumbar perfusion (VLP) chemotherapy has sought to increase drug delivery to the subarachnoid CSF space even in patients with disturbed CSF flow. Recently authors performed phase 1 and 2 clinical trial of VLP chemotherapy with MTX, and 3/4th of patients with increased ICP got controlled ICP and the survival was prolonged. Further trials are required with newly available drugs for CSF chemotherapy. Additionally, new LMC biologic/pharmacodynamic markers for early diagnosis and monitoring of the treatment response are to be identified with the help of advanced molecular biology techniques.

• 대한의용생체공학회:의공학회지
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• 제43권4호
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• pp.193-198
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• 2022

Contrast enhanced magnetic resonance imaging using gadolinium-based contrast agent (GBCA) is a very useful in vivo technique to visualize the inner ear pathology including endolymphatic hydrops. Although systemic intravenous (IV) administration can visualize the perilymph space, the visualization was possible by indirect passage of contrast agent through blood-perilymph barrier. All animal experimental procedures were performed under anesthesia with 5% isoflurane. Lipopolysaccharide (LPS) was instilled into the left tympanic cavity through the tympanic membrane using a sterile 27gauge needle to induce hydrops model. Tucker-Davis Technologies system was used to measure Auditory Brainstem Responses (ABRs). For intracerebroven-tricular (ICV) administration, 25 µmol of GADOVIST (Bayer, Berlin, Germany) was used and diluted GADOVIST injection was 10 µl. MR imaging was acquired with a 9.4 Tesla MRI scanner. Transmit-receive volume coil with 40 mm inner diameter and 75 mm out diameter was used. ICV administration well demonstrated the strong enhancement along the cerebrospinal fluid (CSF) microcirculation pathway including CSF fluid in the subarachnoid space and CSF space of the inner ear structures. On the other hand, IV administration showed no contrast enhancement along the CSF microcirculation pathway and showed weak enhancement in the inner ear structures. In case of rat hydrops model, ICV administration showed that the reduced contrast enhancement in the perilymph space of the hydrops induced inner ear compared to the contrast enhancement in the perilymph space of the normal inner ear. New systemic ICV administration method provide contrast enhancement of GBCA in the inner ear through CSF microcirculation pathway.

• Clinical and Experimental Pediatrics
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• 제46권6호
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• pp.548-553
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• 2003

목 적 : 뇌수막염에서 MMP-9은 뇌혈관 내피하 기질막을 분해하여 혈관-뇌장벽을 파괴하는데 주된 역할을 담당하며 TIMP-1은 MMP-9의 전효소와 복합체를 형성하여 MMP-9의 작용을 선택적으로 억제하는 인자로 알려져 있으나 이들의 상호작용은 아직 밝혀진 바가 별로 없다. 최근 세균성 뇌수막염 환자의 뇌척수액에서 MMP-9과 TIMP-1 측정에 대한 연구가 있었고, 특히 세균성 뇌수막염에서 신경학적 합병증의 예후인자와 관련하여 MMP-9의 역할에 대한 보고들이 있었으나 아직 무균성 뇌수막염 환자를 대상으로 한 보고는 별로 없었고 특히 국내에서 보고된 바는 없었다. 이에 저자들은 무균성 뇌수막염 환아의 혈액과 뇌척수액에서 MMP-9과 TIMP-1의 농도를 측정하여 대조군과 비교하고, MMP-9과 TIMP-1 및 다른 뇌수막염 관련인자들 사이의 상관관계를 비교 분석하고자 하였다. 방 법: 2002년 6월부터 7월까지 강북삼성병원 소아과 내원환자 중 발열과 뇌막자극증상을 보인 40명의 환아들을 대상으로 뇌척수액 검사를 시행하여, 무균성 뇌수막염 소견을 보인 25명을 뇌수막염군, 정상소견을 보인 14명을 대조군으로 하였다. 입원당일 혈액과 뇌척수액을 채취하여 혈액에서 백혈구수를 측정하고, 뇌척수액에서 백혈구수와, 당, 단백농도 및 뇌압을 측정하였다. 나머지 혈액 및 뇌척수액 검체는 실온에서 10분간 2,000g으로 원심분리하여 영하 70도에서 보관후 sandwich ELISA 방법을 이용하여 각각의 검체에서 일시에 MMP-9과 TIMP-1의 농도를 정량하였다. 결 과 : 뇌척수액 MMP-9과 TIMP-1 농도는 뇌수막염군에서 의미있게 증가되었고(P<0.05), 혈청 MMP-9과 TIMP-1 농도는 두 군간에 차이가 없었다. 뇌척수액 MMP-9과 TIMP-1은 서로 의미있는 양의 상관관계를 보였으며($r_s=0.42$, P<0.05), 뇌척수액 MMP-9/TIMP-1 비율은 대조군에 비해 무균성 뇌수막염군에서 의미있게 증가되었다(P<0.05). 뇌척수액 MMP-9과 TIMP-1은 뇌척수액 총백혈구수와 양의 상관관계를 보였다($r_s=0.43$, P<0.05, $r_s=0.48$, P<0.05). 뇌척수액 TIMP-1은 뇌척수액 단백 농도와 양의 상관관계를 보였다($r_s=0.43$, P<0.05). 결 론 : 무균성 뇌수막염 환아의 급성기 뇌척수액에서 MMP-9과 TIMP-1이 의미있는 증가를 보였고, 뇌척수액 TIMP-1은 정상군에서 상대적으로 높은 농도를 보이고 있어 MMP-9과 TIMP-1은 각각 뇌혈관장벽의 파괴와 유지에 관여한다고 생각된다.

• Clinical and Experimental Pediatrics
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• 제48권1호
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• pp.48-54
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• 2005

목 적 : 중추신경계감염의 병리학적인 정보는 아직 미약하고 정확하게 규명된 바가 없지만 최근의 여러 연구들에 의하면 병원균의 직접적인 침습보다는 숙주의 염증반응이 뇌 손상의 중요한 인자가 됨을 밝힘으로써 여러 사이토카인이나 독소, 인터루킨 등이 뇌수막 염증반응을 유도한다고 밝혀져 있다. 최근 세균성 뇌수막염에서 NO, MIP-$1{\alpha}$, lactoferrin의 역할에 대한 보고들이 있었으나 아직 무균성 뇌수막염 환자를 대상으로 한 보고는 별로 없었고 특히 국내에서 보고된 바는 없었다. 이에 저자들은 무균성 뇌수막염 환아의 혈액과 뇌척수액에서 NO, MIP-$1{\alpha}$, lactoferrin의 농도를 측정하여 대조군과 비교하고, 다른 뇌수막염 관련인자들 사이의 상관관계를 비교 분석하고자 하였다. 방 법 : 2002년 6월부터 7월까지 강북삼성병원 소아과 입원환자 중 발열과 뇌막자극증상을 보인 40명의 환아들을 대상으로 뇌척수액 검사를 시행하여, 무균성 뇌수막염 소견을 보인 25명을 뇌수막염군, 정상소견을 보인 15명을 대조군으로 하였다. 입원당일 혈액과 뇌척수액을 채취하여 혈액에서 백혈구수와 CRP를 측정하고, 뇌척수액에서 백혈구수와 당, 단백농도, 뇌압을 측정하였다. 나머지 혈액 및 뇌척수액 검체는 실온에서 10분간 2,000 rpm으로 원심 분리하여 영하 70도에서 보관 후 ELISA 방법을 이용하여 각각의 검체에서 일시에 NO, MIP-$1{\alpha}$, lactoferrin의 농도를 측정하였다. 무균성 뇌수막염군에서 신경학적 후유증을 보인 경우는 없었다. 결 과 : 1) 혈액과 뇌척수액의 NO의 농도는 대조군과 무균성 뇌수막염 사이에 차이를 보이지 않았다. 2) 혈액과 뇌척수액의 MIP-$1{\alpha}$의 농도는 대조군과 무균성 뇌수막염 사이에 차이를 보이지 않았다. 3) 무균성 뇌수막염군의 뇌척수액 lactoferrin 농도는 대조군에 비해 의미 있게 증가되었으며 혈액 lactoferrin 농도는 대조군에 비해 의미 있게 감소되었다. 4) 뇌척수액 lactoferrin 농도는 뇌척수액 백혈구수($r_s=0.449$, P=0.007), 특히 중성구 수와 양의 상관관계를 보였으며($r_s=0.574$, P<0.001), 뇌척수액 단백 농도와 양의 상관관계를 보였다($r_s=0.508$, P=0.002). 결 론 : 무균성 뇌수막염 환아의 뇌척수액에서 lactoferrin은 의미 있게 증가하여 무균성 뇌수막염의 면역 반응에 중요한 역할을 할 것으로 생각되며, 이는 뇌-혈관 장막 붕괴로 인해 혈액에서 뇌척수액으로 유입된 중성구에서 분비되었을 가능성과, 뇌-혈관 장막 붕괴로 인해 혈액에서 뇌척수액으로 직접 유입되었을 가능성이 있는 것으로 생각된다.

• 생명과학회지
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• 제30권12호
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• pp.1118-1127
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• 2020

알츠하이머병은 점진적인 신경세포의 손상과 이로 인해 인지기능 장애를 유발하는 질병이다. 이 질환은 현재로서는 치료할 수 있는 질환이 아니고 진행을 멈추게 할 수 있는 방법이 없다. 그러나 초기에 알츠하이머병을 치료하는 것이 가장 효과적이므로 초기 진단은 증상을 관리할 수 있는 가장 좋은 기회를 제공할 수 있다. 알츠하이머병을 진단하기 위한 바이오마커로는 아밀로이드 베타(Aβ), 병적인 타우, 그리고 신경퇴화가 있고, Aβ의 축적, 인산화 타우는 뇌척수액이나 양전자 방출 단층촬영술을 통해 분석할 수 있다. 그러나 뇌척수액의 채취는 매우 침습적이고 양전자 방출 단층촬영술은 전문적인 고가의 장비가 필요하다. 지난 수십년 동안 빠르고 최소한의 침습성을 가진 바이오마커 분석법을 개발하기 위하여 혈액에 기반한 바이오마커 분석 기술이 연구되어 왔다. 그 중 주목할 만 한 발견이 혈장에서 Aβ의 주요 원천으로 혈소판과의 관련성이다. 아밀로이드 베타는 혈액-뇌 장벽을 통과 할 수 있고 정상 상태에서는 뇌와 혈액 간 평형을 이루게 된다. 흥미롭게도, 여러 임상시험 결과 혈장에서 Aβ42/Aβ40 비율이 가벼운 인지장애 질환과 알츠하이머병에서 감소되어 있는 것을 증명하였다. 종합하면, 이러한 최근의 발견들은 침습성을 최소화한 알츠하이머병의 초기 진단 기술을 개발하는 데 이용될 수 있다. 본 총설에서, 저자들은 알츠하이머병의 바이오마커에 대한 최근 연구결과들, 특히 말초에서 Aβ를 생산하는 혈소판의 역할과 혈액 기반 바이오마커로서의 개발 가능성에 대해 고찰하였다.

• BMB Reports
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• 제57권6호
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• pp.263-272
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• 2024

Amyloid-β (Aβ) is one of the amyloidogenic intrinsically disordered proteins (IDPs) that self-assemble to protein aggregates, incurring cell malfunction and cytotoxicity. While Aβ has been known to regulate multiple physiological functions, such as enhancing synaptic functions, aiding in the recovery of the blood-brain barrier/brain injury, and exhibiting tumor suppression/antimicrobial activities, the hydrophobicity of the primary structure promotes pathological aggregations that are closely associated with the onset of Alzheimer's disease (AD). Aβ proteins consist of multiple isoforms with 37-43 amino acid residues that are produced by the cleavage of amyloid-β precursor protein (APP). The hydrolytic products of APP are secreted to the extracellular regions of neuronal cells. Aβ 1-42 (Aβ42) and Aβ 1-40 (Aβ40) are dominant isoforms whose significance in AD pathogenesis has been highlighted in numerous studies to understand the molecular mechanism and develop AD diagnosis and therapeutic strategies. In this review, we focus on the differences between Aβ42 and Aβ40 in the molecular mechanism of amyloid aggregations mediated by the two additional residues (Ile41 and Ala42) of Aβ42. The current comprehension of Aβ42 and Aβ40 in AD progression is outlined, together with the structural features of Aβ42/Aβ40 amyloid fibrils, and the aggregation mechanisms of Aβ42/Aβ40. Furthermore, the impact of the heterogeneous distribution of Aβ isoforms during amyloid aggregations is discussed in the system mimicking the coexistence of Aβ42 and Aβ40 in human cerebrospinal fluid (CSF) and plasma.

• Journal of Ginseng Research
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• 제45권2호
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• pp.264-272
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• 2021

Background: Gintonin is a ginseng-derived exogenous G-protein-coupled lysophosphatidic acid (LPA) receptor ligand, which exhibits in vitro and in vivo functions against Alzheimer disease (AD) through lysophosphatidic acid 1/3 receptors. A recent study demonstrated that systemic treatment with gintonin enhances paracellular permeability of the blood-brain barrier (BBB) through the LPA1/3 receptor. However, little is known about whether gintonin can enhance brain delivery of donepezil (DPZ) (Aricept), which is a representative cognition-improving drug used in AD clinics. In the present study, we examined whether systemic administration of gintonin can stimulate brain delivery of DPZ. Methods: We administered gintonin and DPZ alone or coadministered gintonin with DPZ intravenously or orally to rats. Then we collected the cerebral spinal fluid (CSF) and serum and determined the DPZ concentration through liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Results: Intravenous, but not oral, coadministration of gintonin with DPZ increased the CSF concentration of DPZ in a concentration- and time-dependent manner. Gintonin-mediated enhancement of brain delivery of DPZ was blocked by Ki16425, a LPA1/3 receptor antagonist. Coadministration of vascular endothelial growth factor (VEGF) + gintonin with DPZ similarly increased CSF DPZ concentration. However, gintonin-mediated enhancement of brain delivery of DPZ was blocked by axitinip, a VEGF receptor antagonist. Mannitol, a BBB disrupting agent that increases the BBB permeability, enhanced gintonin-mediated enhancement of brain delivery of DPZ. Conclusions: We found that intravenous, but not oral, coadministration of gintonin facilitates brain delivery of DPZ from plasma via LPA1/3 and VEGF receptors. Gintonin is a potential candidate as a ginseng-derived novel agent for the brain delivery of DPZ for treatment of patients with AD.

• 동의생리병리학회지
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• 제33권6호
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• pp.356-362
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• 2019

Scutellaria baicalensis (SB) has widely used in the treatment for various brain diseases in the field of Oriental medicine. Biofermantation of SB can make major chemical constituents of SB to pass blood-brain barrier easily and to have more potent anti-oxidant ability. There is a little information about the contribution of fermented SB (FSB) to the formation or maintenance of the neural plasticity in the hippocampus. The purpose of this study was to evaluate effects of FSB extract on hydrogen peroxide (H₂O₂) - induced impairments of the induction and maintenance of long-term potentiation (LTP), an electrophysiological marker for the neural plasticity in the hippocampus. From hippocampal slices of rats, the field excitatory postsynaptic potentials (fEPSPs) were evoked by the electrical stimulation to the Schaffer collaterals - commissural fibers in the CA1 areas and LTP by theta-burst stimulation by using 64 - channels in vitro multi-extracellular recording system. In order to induce oxidative stress to hippocampal slices two different concentrations (200, 400 μM) of H₂O₂ were given to the perfused aCSF before and after the LTP induction, respectively. The ethanol extract of FBS with concentration of 25 ㎍/ml, 50 ㎍/ml was diluted in perfused aCSF that had 200 μM H₂O₂, respectively. Oxidative stress by the treatment of H₂O₂ resulted in decrease of the induction rate of LTP in the CA1 area with a dose - dependent manner. However, the ethanol extract of FSB prevented the reduction of the induction rate of LTP caused by H₂O₂ - induced oxidative stress with a dose - dependent manner. These results may support a potential application of FSB to ameliorate impairments of hippocampal dependent neural plasticity or memory caused by oxidative stress.