Single Exposure to Cocaine Impairs Reinforcement Learning by Potentiating the Activity of Neurons in the Direct Striatal Pathway in Mice / 神经科学通报·英文版

Plasticity in the glutamatergic synapses on striatal medium spiny neurons (MSNs) is not only essential for behavioral adaptation but also extremely vulnerable to drugs of abuse. Modulation on these synapses by even a single exposure to an addictive drug may interfere with the plasticity required by behavioral learning and thus produce impairment. In the present work, we found that the negative reinforcement learning, escaping mild foot-shocks by correct nose-poking, was impaired by a single in vivo exposure to 20 mg/kg cocaine 24 h before the learning in mice. Either a single exposure to cocaine or reinforcement learning potentiates the glutamatergic synapses on MSNs expressing the striatal dopamine 1 (D1) receptor (D1-MSNs). However, 24 h after the cocaine exposure, the potentiation required for reinforcement learning was disrupted. Specific manipulation of the activity of striatal D1-MSNs in D1-cre mice demonstrated that activation of these MSNs impaired reinforcement learning in normal D1-cre mice, but inhibition of these neurons reversed the reinforcement learning impairment induced by cocaine. The results suggest that cocaine potentiates the activity of direct pathway neurons in the dorsomedial striatum and this potentiation might disrupt the potentiation produced during and required for reinforcement learning.

Review on clinical update of essential tremor.

Essential tremor (ET) is considered a benign disease without any pathological changes. Nevertheless, this point of view has recently been challenged. In recent years, studies have shown that ET occurs with other non-motor symptoms, such as cognitive deficits, depression, anxiety, balance disorder, hearing impairment, olfactory dysfunction and sleep problems. Advancements in neuroimaging have revealed widespread alterations in the brain, and cerebellar involvement was the most consistent finding. In addition, studies have also shown that ET patients might experience poor quality of life, reflecting motor or non-motor symptoms. Both pharmacotherapy and non-pharmacotherapy have recently been suggested for the treatment of ET. This review briefly describes the current information on ET, including the non-movement symptoms, neuroimaging findings, the impact on daily life and ET therapy.

Relationship of the Waist Circumference with the Blood Pressure,Lipid and Glucose Metabolism in 7660 Adults / 中国慢性病预防与控制

Objective To evaluate the effect of twaist circumference(WC)on the blood pressure,lipid and glucose metabolism. Methods A baseline investigative data from community intervention target population for cardiovascular disease in Liuzhou was used. There were 7 660 residents (male was 3 894,female was 3 766),average aged 40.5?12.2 years. Their height,weight,WC,blood pressure,fasting plasma lipid and fasting plasma glucose(FPG) were detected. By WC length,they were divided as M