GABAergic regulation of REM sleep in reticularis pontis oralis (RPO) and caudalis (RPC) in rats
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چکیده
The nucleus reticularis pontis oralis (RPO) and nucleus reticularis pontis caudalis (RPC) are implicated in the generation of rapid eye movement sleep (REM). Work in cats has indicated that GABA in RPO plays a role in the regulation of REM. We assessed REM after local microinjections into RPO and RPC of the GABAA agonist, muscimol (MUS), and the GABAA antagonist, bicuculline (BIC). Rats (90 day old male Sprague-Dawley) were implanted with electrodes for recording EEG and EMG. Guide cannulae were aimed into RPO (n=9) and RPC (n=8) for microinjecting MUS (200, 1000.0 μM) and BIC (0.056, 0.333, 1.0, 1000.0 and 10000.0 μM). Animals received bilateral microinjections of saline, MUS and BIC (0.2 μl microinjected at 0.1 μl / min) into each region followed by six h sleep recordings. In RPO, MUS (1000.0 μM) suppressed REM and BIC (1000.0 μM) enhanced REM. In RPC, MUS (200, 1000.0 μM) suppressed REM, but BIC (1000.0 μM and less) did not significantly affect REM. Higher concentrations of BIC (10000.0 μM) injected into RPO (n=9) and RPC (n=4) produced wakefulness and escape behavior. The results indicate that GABA in RPO/RPC is involved in the regulation of REM, and suggest site-specific differences in this regulation.
منابع مشابه
GABAergic regulation of REM sleep in reticularis pontis oralis and caudalis in rats.
The nucleus reticularis pontis oralis (RPO) and nucleus reticularis pontis caudalis (RPC) are implicated in the generation of rapid eye movement sleep (REM). Work in cats has indicated that GABA in RPO plays a role in the regulation of REM. We assessed REM after local microinjections into RPO and RPC of the gamma-aminobutyric acid-A (GABA(A)) agonist, muscimol (MUS), and the GABA(A) antagonist,...
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