The main purpose of this study was to investigate the protective actions of captopril and cicaprost on changes of membrane fluidity of cultured neonatal rat myocardial cells exposed to anoxia and sugar deprivation.Lip...The main purpose of this study was to investigate the protective actions of captopril and cicaprost on changes of membrane fluidity of cultured neonatal rat myocardial cells exposed to anoxia and sugar deprivation.Lipid peroxidation level estimated by determining the thiobarbituric acid reactive substance(TBARS)content and lactate dehydrogenase(LDH)released in culture medium was also observed in order to examine other membrane-related changes due to anoxia.Membrane fluidity was monitored by measuring changes in the steady state fluorescence anisotropy(r_s)by fluorescence spectroscopy.The r_s value,TBARS level and LDH release were significantly increased after 3 h anoxia.Captopril(180 μmol/L),cicaprost(30 nmol/L)and indomethacin(1μmol/L)did not alter r_s, TBARS level and LDH activity of normal cultured neonatal rat myocardial cells.However,both captopril and cicaprost significantly prevented the increases of r_s,TBARS content and LDH release in those cells exposed to anoxia and sugar deprivation.lndomethacin abolished the actions of captopril on TBARS production and LDH release,but maintained its membrane fluidity protection.These results indicate that captopril and cicaprost protect membrane fluidity and lipid peroxidation changes in anoxia- injured myocardial cells.The action mechanism of captopril may be due,in part,to stimulation of prostacyclin synthesis and/or release.展开更多
Objective:To investigate the neural electrophysiologieal activity underlying Chinese and Eng- lish Stroop tasks for Chinese English bilinguals.Methods:Event-related potentials(ERPs)were recorded in 14 Chinese bilingua...Objective:To investigate the neural electrophysiologieal activity underlying Chinese and Eng- lish Stroop tasks for Chinese English bilinguals.Methods:Event-related potentials(ERPs)were recorded in 14 Chinese bilinguals with a moderate command of English when they performed the Stroop task pre- sented in English words and Chinese characters,respectively.Results:In Chinese task version,it was found an increased positivity over bilateral front-polar regions on incongruent trials compared with congru- ent trials,followed by an increased negativity over fronto-central region and an increased positivity over occipital region.While in English task version,only the increased negativity was observed over fronto-cen- tral region,but with reduced amplitude and anterior distribution.Conclusion:This increased negativity was proposed as an index of the resolution processes of conflicting information in the incongruent situa- tion.The increased positivity over occipital region on Chinese incongruent trials may indicate visually rechecking effect for Chinese character.展开更多
基金Supported by a grant for young researcher from Ministry of Public Health of P.R.C.
文摘The main purpose of this study was to investigate the protective actions of captopril and cicaprost on changes of membrane fluidity of cultured neonatal rat myocardial cells exposed to anoxia and sugar deprivation.Lipid peroxidation level estimated by determining the thiobarbituric acid reactive substance(TBARS)content and lactate dehydrogenase(LDH)released in culture medium was also observed in order to examine other membrane-related changes due to anoxia.Membrane fluidity was monitored by measuring changes in the steady state fluorescence anisotropy(r_s)by fluorescence spectroscopy.The r_s value,TBARS level and LDH release were significantly increased after 3 h anoxia.Captopril(180 μmol/L),cicaprost(30 nmol/L)and indomethacin(1μmol/L)did not alter r_s, TBARS level and LDH activity of normal cultured neonatal rat myocardial cells.However,both captopril and cicaprost significantly prevented the increases of r_s,TBARS content and LDH release in those cells exposed to anoxia and sugar deprivation.lndomethacin abolished the actions of captopril on TBARS production and LDH release,but maintained its membrane fluidity protection.These results indicate that captopril and cicaprost protect membrane fluidity and lipid peroxidation changes in anoxia- injured myocardial cells.The action mechanism of captopril may be due,in part,to stimulation of prostacyclin synthesis and/or release.
文摘Objective:To investigate the neural electrophysiologieal activity underlying Chinese and Eng- lish Stroop tasks for Chinese English bilinguals.Methods:Event-related potentials(ERPs)were recorded in 14 Chinese bilinguals with a moderate command of English when they performed the Stroop task pre- sented in English words and Chinese characters,respectively.Results:In Chinese task version,it was found an increased positivity over bilateral front-polar regions on incongruent trials compared with congru- ent trials,followed by an increased negativity over fronto-central region and an increased positivity over occipital region.While in English task version,only the increased negativity was observed over fronto-cen- tral region,but with reduced amplitude and anterior distribution.Conclusion:This increased negativity was proposed as an index of the resolution processes of conflicting information in the incongruent situa- tion.The increased positivity over occipital region on Chinese incongruent trials may indicate visually rechecking effect for Chinese character.
