Nonprotein coding dendritic BC1 RNA regulates translation of mRNAs in neurons. We examined two lines of BC1 knockout mice and report that loss of BC1 RNA exaggerates group I mGluR-stimulated LTD of the Schaffer collateral synapse, with one of the lines showing a much more enhanced DHPG-induced LTD than the other. When the animals were given the hippocampus-synaptic plasticity-dependent active place avoidance task, learning and memory were impaired in the BC1-KO line with the more severely altered DHPG-induced LTD. These findings indicate a role for BC1 RNA control of mGluR-dependent synaptic function in hippocampus and associated cognitive ability.

Muscle weakness and enhanced fatigue are common complaints of cancer patients undergoing chemotherapy. In order to evaluate the underlying mechanisms, the present study assessed the acute effects of the chemotherapeutic drug, doxorubicin, on spontaneous motor activity and swimming performance of mice. Before and after i.p. injection of doxorubicin at 25 mg/kg into each mouse, the number of spontaneous movements was monitored for 24 hr using Columbus Instruments Opto‐varimax‐mini activity meter, and the integrated swimming activity (V.sec) was recorded for 40 min using a digital swimming monitor (Pagala, 1999).Doxorubicin, within the clinical dose range, significantly reduced the stereotypic, ambulatory, and thus the total number of spontaneous movements of the mice in a 24 hr period (Table 1). Doxorubicin also caused a significant reduction in the integrated swimming activity of the mice over a 40 min period (Table 1). These results indicate that chemotherapeutic agents may significantly decrease the motivation and endurance for physical activity.Supported by a special grant from Maimonides Med. Ctr.

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