Objective Numerous studies have described both motor defects and cognitive impairments in several strains of rodents following 3-nitropropionic acid （3-NP） intoxication. In the present study, we investigated spatial...Objective Numerous studies have described both motor defects and cognitive impairments in several strains of rodents following 3-nitropropionic acid （3-NP） intoxication. In the present study, we investigated spatial recognition memory in Kunming mice that just recovered from motor defects induced by 3-NP. Methods Mouse model was made by systemic subacute 3-NP treatment, and spatial recognition memory was measured through the Y-maze Test, a simple two-trial recognition test. Results （1） On day 15 following 3-NP treatment, affected Kunming mice did not show motor defects in the Rotarod test and presented normal gait again. （2） In the following Y-maze test after lh interval, the percentage （90.0%） of mice showing novel ann preference in 3-NP treatment group was significantly higher than the random chance level （50%）, although it was only slightly higher than that （83.3%） in control group. On day 45 after 3-NP treatment, mice failed to choose unfamiliar novel arm as first choice, and the same occured in the control group. （3） For both post-intoxicated （on day 15 and day 45 following 3-NP treatment） and control groups, the duration in the novel ann and the frequency of entering it, were longer and higher compared with familiar start and other arms. For these mice that recently recovered from motor defects following 3-NP intoxication, no spatial memory deficits were observed through Y-maze Test. Conclusion Kunming mice used in our assays might possess resistance to cognitive impairment induced by 3-NP, which is consistent with previous findings in Swiss EPM-M1 mice.展开更多
Objective To investigate the alterations of cardiac electrophysiological properties and substantial mechanism and find the stable arrhythmia mouse model in Kunming （KM） and C57BL6/J （C57） mice. Methods Electrocar...Objective To investigate the alterations of cardiac electrophysiological properties and substantial mechanism and find the stable arrhythmia mouse model in Kunming （KM） and C57BL6/J （C57） mice. Methods Electrocardiogram recordings were used to analyze the QT interval in vivo, and mono- phasic action potential of right and left ventricular epicardium was recorded to elicit changes of action potential duration （APD） in conventional and programmed electrical stimulation （PES）. Transient outward potassium current （Its,） was recorded via whole-cell patch-clamp technique in single right and left epicardial myocytes. Results QT interval was prolonged in KM mice relative to C57 mice （62.51±4.47 ms vs. 52.59±4.85 ms, P〈0.05）. The APD at 50% repolarization of the left ventricular epicardium （18.60±0.91 ms vs. 12.90±0.35 ms）, and APDs at 50% （17.31±6.05 ms vs. 12.00±3.24 ms） and 70% repolarization （36.13±5.32 ms vs. 2 1.95±8.06 ms） of the right ventricular epicardium in KM mice were significantly pro- longed compared with C57 mice, respectively （all P〈0.05）. KM mice were more sensitive to PES-induced ventricular tachycardia （25%, 3 of 12 hearts）, and especially to Burst-induced ventricular tachycardia （50%, 6 of 12 hearts） compared with C57 mice, which were 20% （2 of 10 hearts） and 30% （3 of 10 hearts） respec- tively. It,, densities both in the left and right ventricular epicardial myocytes from KM mice were significantly decreased compared with C57 mice, respectively （all P〈0.01）. Conclusion Our data showed that KM mice with tile prolonged QT interval and APD are ruiner- abilities to ventricular arrhythmia, which are attributed to lower Ito densities in ventricular myocytes ob- tained from KM mice than that from C57 mice.展开更多
Objective:To establish a new way to collect superovulated oocytes or zygotes repeatedlyfrom an individual mouse.Methods:Superovulations were induced by injection PMSG and hCG in Kunming strainmice.The ampullaes of ovi...Objective:To establish a new way to collect superovulated oocytes or zygotes repeatedlyfrom an individual mouse.Methods:Superovulations were induced by injection PMSG and hCG in Kunming strainmice.The ampullaes of oviduct of all anaesthetised mouse were put in a specially designed'U'sink and released.The second and third times of PMSG injection were made on the sixth day andeleventh day after the first superovulation injection.The capacity of development was examinedby in vitro culture of parthenogenesis activation oocytes.Results:Development to blastocyst stage was not significantly different between the first andsecond time collection.The percentage of blastocyst stage in CD and Sr^(++) treatment was signifi-cantly higher(P<0.05)than the oocytes treated in CB and Sr^(++).Conclusion:This method enables us to collect oocytes or zygotes repeatedly from one individ-ual mouse in an interval as short as 5 days and without influence on the quality of oocytes.展开更多
基金the Medical Research Foundation of Tongji University, China (No.1509219020).
文摘Objective Numerous studies have described both motor defects and cognitive impairments in several strains of rodents following 3-nitropropionic acid （3-NP） intoxication. In the present study, we investigated spatial recognition memory in Kunming mice that just recovered from motor defects induced by 3-NP. Methods Mouse model was made by systemic subacute 3-NP treatment, and spatial recognition memory was measured through the Y-maze Test, a simple two-trial recognition test. Results （1） On day 15 following 3-NP treatment, affected Kunming mice did not show motor defects in the Rotarod test and presented normal gait again. （2） In the following Y-maze test after lh interval, the percentage （90.0%） of mice showing novel ann preference in 3-NP treatment group was significantly higher than the random chance level （50%）, although it was only slightly higher than that （83.3%） in control group. On day 45 after 3-NP treatment, mice failed to choose unfamiliar novel arm as first choice, and the same occured in the control group. （3） For both post-intoxicated （on day 15 and day 45 following 3-NP treatment） and control groups, the duration in the novel ann and the frequency of entering it, were longer and higher compared with familiar start and other arms. For these mice that recently recovered from motor defects following 3-NP intoxication, no spatial memory deficits were observed through Y-maze Test. Conclusion Kunming mice used in our assays might possess resistance to cognitive impairment induced by 3-NP, which is consistent with previous findings in Swiss EPM-M1 mice.
基金Supported by the National Natural Science Foundation of China(81070142)Natural Science Foundation of Hubei Province (2011CDB504)
文摘Objective To investigate the alterations of cardiac electrophysiological properties and substantial mechanism and find the stable arrhythmia mouse model in Kunming （KM） and C57BL6/J （C57） mice. Methods Electrocardiogram recordings were used to analyze the QT interval in vivo, and mono- phasic action potential of right and left ventricular epicardium was recorded to elicit changes of action potential duration （APD） in conventional and programmed electrical stimulation （PES）. Transient outward potassium current （Its,） was recorded via whole-cell patch-clamp technique in single right and left epicardial myocytes. Results QT interval was prolonged in KM mice relative to C57 mice （62.51±4.47 ms vs. 52.59±4.85 ms, P〈0.05）. The APD at 50% repolarization of the left ventricular epicardium （18.60±0.91 ms vs. 12.90±0.35 ms）, and APDs at 50% （17.31±6.05 ms vs. 12.00±3.24 ms） and 70% repolarization （36.13±5.32 ms vs. 2 1.95±8.06 ms） of the right ventricular epicardium in KM mice were significantly pro- longed compared with C57 mice, respectively （all P〈0.05）. KM mice were more sensitive to PES-induced ventricular tachycardia （25%, 3 of 12 hearts）, and especially to Burst-induced ventricular tachycardia （50%, 6 of 12 hearts） compared with C57 mice, which were 20% （2 of 10 hearts） and 30% （3 of 10 hearts） respec- tively. It,, densities both in the left and right ventricular epicardial myocytes from KM mice were significantly decreased compared with C57 mice, respectively （all P〈0.01）. Conclusion Our data showed that KM mice with tile prolonged QT interval and APD are ruiner- abilities to ventricular arrhythmia, which are attributed to lower Ito densities in ventricular myocytes ob- tained from KM mice than that from C57 mice.
文摘Objective:To establish a new way to collect superovulated oocytes or zygotes repeatedlyfrom an individual mouse.Methods:Superovulations were induced by injection PMSG and hCG in Kunming strainmice.The ampullaes of oviduct of all anaesthetised mouse were put in a specially designed'U'sink and released.The second and third times of PMSG injection were made on the sixth day andeleventh day after the first superovulation injection.The capacity of development was examinedby in vitro culture of parthenogenesis activation oocytes.Results:Development to blastocyst stage was not significantly different between the first andsecond time collection.The percentage of blastocyst stage in CD and Sr^(++) treatment was signifi-cantly higher(P<0.05)than the oocytes treated in CB and Sr^(++).Conclusion:This method enables us to collect oocytes or zygotes repeatedly from one individ-ual mouse in an interval as short as 5 days and without influence on the quality of oocytes.
