OBJECTIVE To investigate the role of chemokine CCL2 in leaning memory in rats and the mechanism of hippocampal neuronal apoptosis.METHODS Stereotaxic technique was used in this study to infuse CCL2(0.5,5 and50 ng) int...OBJECTIVE To investigate the role of chemokine CCL2 in leaning memory in rats and the mechanism of hippocampal neuronal apoptosis.METHODS Stereotaxic technique was used in this study to infuse CCL2(0.5,5 and50 ng) into bilateral hippocampus,sham group was received the equal volume of sterile saline.Morris water maze(MWM) was employed to assess the learning and memory ability of rats.Quantitative real-time PCR(RT-PCR) was used to detect the relative expression of caspase 3,Bax and Bcl-2 in hippocampus.RESULTS The results of the place navigation task showed that compared to the sham group(18.66±0.82) s,the latency in each model groups [24.18±1.08,25.99±1.96,(28.67±1.47) s] were significantly extended(P<0.05) while the swimming speed have no difference.In probe trial,the crossing times of each model groups [2.86±0.59,2.89 ±0.39,(2.50±0.37) s] were shorter than sham group(4.50±0.76) s(P<0.05).The result of RT-PCR showed that the relative expression of caspase 3 in CCL2 5 ng group(1.275±0.078)and CCL2 50 ng groups(1.283±0.043) in higher than sham group(1.000±0.000),as the same as Bax(1.107±0.028,1.096±0.015).Yet the relative expression of Bcl-2 has no significant difference among groups.CONCLUSION CCL2 may impaired learning and memory in rats in dose-dependent manner.The effect to induce hippocampal neuronal apoptosis may mediated by caspase 3 activation and Bax regulation.展开更多
The role of the thalamus in highlevel cognitive function such as learning and memory remains poorly understood.Here we systematically examined the role of paraventricular thalamus(PVT) in associative learning.We train...The role of the thalamus in highlevel cognitive function such as learning and memory remains poorly understood.Here we systematically examined the role of paraventricular thalamus(PVT) in associative learning.We trained mice with olfactory conditioning task in which different olfactory cues were associated with different outcomes includes reward,punishment or nothing.Both fiber photometry and single-unit recordings revealed that PVT were robustly activated by a variety of behaviorally significant events including reinforcing stimuli and their predicting cues,as well as omission of the expected reward.PVT responses are proportional to the stimulus intensity and modulated by changes in homeostatic state or behavioral context.Optogenetic inhibition of the PVT responses suppresses appetitive or aversive associative learning and reward extinction.Our findings demonstrate that the PVT gates associative learning by providing a dynamic representation of stimulus salience.展开更多
基金National Natural Science Foundation of China(81360192,81660213).
文摘OBJECTIVE To investigate the role of chemokine CCL2 in leaning memory in rats and the mechanism of hippocampal neuronal apoptosis.METHODS Stereotaxic technique was used in this study to infuse CCL2(0.5,5 and50 ng) into bilateral hippocampus,sham group was received the equal volume of sterile saline.Morris water maze(MWM) was employed to assess the learning and memory ability of rats.Quantitative real-time PCR(RT-PCR) was used to detect the relative expression of caspase 3,Bax and Bcl-2 in hippocampus.RESULTS The results of the place navigation task showed that compared to the sham group(18.66±0.82) s,the latency in each model groups [24.18±1.08,25.99±1.96,(28.67±1.47) s] were significantly extended(P<0.05) while the swimming speed have no difference.In probe trial,the crossing times of each model groups [2.86±0.59,2.89 ±0.39,(2.50±0.37) s] were shorter than sham group(4.50±0.76) s(P<0.05).The result of RT-PCR showed that the relative expression of caspase 3 in CCL2 5 ng group(1.275±0.078)and CCL2 50 ng groups(1.283±0.043) in higher than sham group(1.000±0.000),as the same as Bax(1.107±0.028,1.096±0.015).Yet the relative expression of Bcl-2 has no significant difference among groups.CONCLUSION CCL2 may impaired learning and memory in rats in dose-dependent manner.The effect to induce hippocampal neuronal apoptosis may mediated by caspase 3 activation and Bax regulation.
文摘The role of the thalamus in highlevel cognitive function such as learning and memory remains poorly understood.Here we systematically examined the role of paraventricular thalamus(PVT) in associative learning.We trained mice with olfactory conditioning task in which different olfactory cues were associated with different outcomes includes reward,punishment or nothing.Both fiber photometry and single-unit recordings revealed that PVT were robustly activated by a variety of behaviorally significant events including reinforcing stimuli and their predicting cues,as well as omission of the expected reward.PVT responses are proportional to the stimulus intensity and modulated by changes in homeostatic state or behavioral context.Optogenetic inhibition of the PVT responses suppresses appetitive or aversive associative learning and reward extinction.Our findings demonstrate that the PVT gates associative learning by providing a dynamic representation of stimulus salience.
