RHIM, H GLAUM, SR MILLER, RJ 2024-01-21T22:37:11Z 2024-01-21T22:37:11Z 2021-08-31 1993-02 0022-3565 https://pubs.kist.re.kr/handle/201004/146121 We examined the effects of agonists at mu, delta and kappa opioid receptors on neurons located in the nucleus tractus solitarius of the rat using whole-cell patch-clamp recordings in brainstem slices. The mu selective opioid agonist DAMGO hyperpolarized most neurons tested. This effect was associated with the activation of a K+-conductance. The effect of DAMGO tended to desensitize and was blocked by naloxone. Dynorphin A also produced this effect. However, the kappa-1-selective opioid agonist U-69593 and two de/ta-selective opioid agonists did not. DAMGO also depressed glutamate-mediated excitatory postsynaptic potentials and GABA-mediated evoked by stimulation of the tractus solitarius. Dynorphin A, U-69593 and delta-opioid agonists also reduced the excitatory postsynaptic potential, although they were less effective than DAMGO. The presynaptic inhibitory effects of DAMGO were also blocked by naloxone, but did not desensitize. These actions may help to explain the ability of opiates to modulate a variety of autonomic reflexes. English WILLIAMS & WILKINS LOCUS COERULEUS NEURONS POTASSIUM CONDUCTANCE MEDULLA-OBLONGATA OPIATE RECEPTORS MU-RECEPTORS NORADRENALINE CURRENTS SOMATOSTATIN NERVE CATECHOLAMINES SELECTIVE OPIOID AGONISTS MODULATE AFFERENT TRANSMISSION IN THE RAT NUCLEUS TRACTUS-SOLITARIUS Article 1 JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS, v.264, no.2, pp.795 - 800 JOURNAL OF PHARMACOLOGY AND EXPERIMENTAL THERAPEUTICS 264 2 795 800 scie scopus A1993KM43200039 Pharmacology & Pharmacy Pharmacology & Pharmacy Article LOCUS COERULEUS NEURONS POTASSIUM CONDUCTANCE MEDULLA-OBLONGATA OPIATE RECEPTORS MU-RECEPTORS NORADRENALINE CURRENTS SOMATOSTATIN NERVE CATECHOLAMINES opioids NTS potassium channels