Dissociating reward sensitivity and negative urgency effects on impulsivity in the five-choice serial reaction time task

Brain and Neuroscience Advances

article

Maria A. Samara¹  George D. Oikonomou¹  George Trompoukis¹  Georgia Madarou¹  Maria Adamopoulou¹  Costas Papatheodoropoulos² 

[1] Laboratory of Neurophysiology, Department of Medicine, University of Patras;Laboratory of Physiology, Department of Medicine, University of Patras

关键词: Hippocampus;    dorsoventral;    septotemporal;    longitudinal axis;    short-term synaptic plasticity;    adenosine receptors;    GABAb receptors;    neuromodulation;    in vitro;    rat;   

DOI  :  10.1177/23982128221106315

学科分类：医学（综合）

来源: Sage Journals

【 摘 要 】

Short-term synaptic plasticity represents a fundamental mechanism in neural information processing and is regulated by neuromodulators. Here, using field recordings from the CA1 region of adult rat hippocampal slices, we show that excitatory synaptic transmission is suppressed by strong but not moderate activation of adenosine A 1 receptors by 2-Chloro-N 6 -cyclopentyladenosine (CCPA) more in the dorsal than the ventral hippocampus; in contrast, both mild and strong activation of GABA B receptors by baclofen (1 μM, 10 μM) suppress synaptic transmission more in the ventral than the dorsal hippocampus. Using a 10-pulse stimulation train of variable frequency, we found that CCPA modulates short-term synaptic plasticity independently of the suppression of synaptic transmission in both segments of the hippocampus and at stimulation frequencies greater than 10 Hz. However, specifically regarding the paired-pulse ratio (PPR) and frequency facilitation/depression (FF/D) we found significant drug action before but not after adjusting conditioning responses to control levels. Activation of GABA B Rs by baclofen suppressed synaptic transmission more in the ventral than the dorsal hippocampus. Furthermore, relatively high (10 μM) but not low (1 μM) baclofen concentration enhanced both PPR and FF in both hippocampal segments at stimulation frequencies greater than 1 Hz, independently of the suppression of synaptic transmission by baclofen. These results show that A 1 Rs and GABA B Rs control synaptic transmission more effectively in the dorsal and the ventral hippocampus, respectively, and suggest that these receptors modulate PPR and FF/D at different frequency bands of afferent input, in both segments of the hippocampus.

【 授权许可】

CC BY|CC BY-NC