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Currents evoked by GABA and glycine in acutely dissociated neurons from the rat medial preoptic nucleus.

Astra Pain Control AB, Novum Unit, Huddinge, Sweden.
Brain Research (Impact Factor: 2.83). 11/1997; 770(1-2):256-60. DOI: 10.1016/S0006-8993(97)00857-3
Source: PubMed

ABSTRACT The responses of acutely dissociated medial preoptic neurons to application of GABA, and glycine were studied using the perforated-patch whole-cell recording technique under voltage-clamp conditions. GABA, at a concentration of 1 mM, evoked outward currents in all cells (n = 33) when studied at potentials positive to -80 mV. The I-V relation was roughly linear. The currents evoked by GABA were partially blocked by 25-75 microM picrotoxin and were also partially or completely blocked by 100-200 microM bicuculline. Glycine, at a concentration of 1 mM, did also evoke outward currents in all cells (n = 12) when studied at potentials positive to -75 mV. The I-V relation was roughly linear. The currents evoked by glycine were largely blocked by 1 microM strychnine. In conclusion, the present work demonstrates that neurons from the medial preoptic nucleus of rat directly respond to the inhibitory transmitters GABA and glycine with currents that can be attributed to GABAA receptors and glycine receptors respectively.

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    • "A first series of experiments was performed with amphotericin B as the perforating substance. In agreement with our previous report (Karlsson et al., 1997a), all MPN neurons tested (n = 114) responded to application of GABA as well as to glycine (Fig. 2 A). The concentration–response curves show apparent EC 50 values of 16 and 104 µM, respectively (Fig. 2 A, bottom). "
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