Intra-nucleus accumbens shell injection of baclofen blocks the reconsolidation of conditioned place preference in morphine-addicted mice / 生理学报

Preclinical studies suggest that the GABA receptor is a potential target for treatment of substance use disorders. Baclofen (BLF), a prototypical GABA receptor agonist, is the only specific GABA receptor agonist available for application in clinical addiction treatment. The nucleus accumbens shell (AcbSh) is a key node in the circuit that controls reward-directed behavior. However, the relationship between GABA receptors in the AcbSh and memory reconsolidation was unclear. The aim of this study was to investigate the effect of intra-AcbSh injection of BLF on the reconsolidation of morphine reward memory. Male C57BL/6J mice were used to establish morphine conditioned place preference (CPP) model and carry out morphine reward memory retrieval and activation experiment. The effects of intra-AcbSh injection of BLF on morphine-induced CPP, reinstatement of CPP and locomotor activity were observed after environmental cues activating morphine reward memory. The results showed that intra-AcbSh injection of BLF (0.06 nmol/0.2 μL/side or 0.12 nmol/0.2 μL/side), rather than vehicle or BLF (0.01 nmol/0.2 μL/side), following morphine reward memory retrieval abolished morphine-induced CPP by disrupting its reconsolidation in mice. Moreover, this effect persisted for more than 14 days, which was not reversed by a morphine priming injection. Furthermore, intra-AcbSh injection of BLF without morphine reward memory retrieval had no effect on morphine-associated reward memory. Interestingly, administration of BLF into the AcbSh had no effect on the locomotor activity of mice during testing phase. Based on these results, we concluded that intra-AcbSh injection of BLF following morphine reward memory could erase morphine-induced CPP by disrupting its reconsolidation. Activating GABA receptor in AcbSh during drug memory reconsolidation may be a potential approach to prevent drug relapse.

Advances in the prediction and treatment of recurrent pancreatic cancer / 医学研究生学报

Patients with pancreatic adenocarcinoma who underwent surgical resection have poor prognosis, with the recurrence rate of over 80% within two years. Currently, the treatment of recurrent pancreatic cancer is still in the exploratory phase, and the efficacy is only limited to chemotherapy. In addition, there are differences in the efficacy of different chemotherapy schemes, and there is no unified chemotherapy scheme. Meanwhile, new radiotherapy and surgical treatment have been proposed for the treatment of recurrent pancreatic cancer, but its efficacy is yet to be confirmed. This paper summarizes the factors to predict postoperative recurrence, various chemotherapy schemes and new radiotherapy methods, reviews and analyzes the effectiveness of surgical treatment on recurrent pancreatic cancer.