Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Inhibition of calcium currents in rat colon sensory neurons by K- but not mu- or delta-opioids
Autore:
Su, X; Wachtel, RE; Gebhart, GF;
Indirizzi:
Univ Iowa, Dept Pharmacol, Coll Med, Iowa City, IA 52242 USA Univ Iowa Iowa City IA USA 52242 macol, Coll Med, Iowa City, IA 52242 USA Univ Iowa, Coll Med, Dept Anesthesia, Iowa City, IA 52242 USA Univ Iowa Iowa City IA USA 52242 Dept Anesthesia, Iowa City, IA 52242 USA Vet Affairs Med Ctr, Iowa City, IA 52246 USA Vet Affairs Med Ctr Iowa City IA USA 52246 d Ctr, Iowa City, IA 52246 USA
Titolo Testata:
JOURNAL OF NEUROPHYSIOLOGY
fascicolo: 6, volume: 80, anno: 1998,
pagine: 3112 - 3119
SICI:
0022-3077(199812)80:6<3112:IOCCIR>2.0.ZU;2-R
Fonte:
ISI
Lingua:
ENG
Soggetto:
ROOT GANGLION NEURONS; DYNORPHIN-A; HIGH-THRESHOLD; NALOXONE BENZOYLHYDRAZONE; POLYMODAL NOCICEPTORS; NOR-BINALTORPHIMINE; MEDIATED REDUCTION; RECEPTOR-BINDING; CA2+ CHANNELS; KAPPA;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
35
Recensione:
Indirizzi per estratti:
Indirizzo: Su, X UnivAIowa, Dept Pharmacol, Coll Med, Bowen Sci Bldg, Iowa City, IA 52242 US Univ Iowa Bowen Sci Bldg Iowa City IA USA 52242 wa City, IA 52242 US
Citazione:
X. Su et al., "Inhibition of calcium currents in rat colon sensory neurons by K- but not mu- or delta-opioids", J NEUROPHYS, 80(6), 1998, pp. 3112-3119

Abstract

We previously reported that kappa-, but not mu- or delta-opioid receptor agonists (ORAs) have selective, potentially useful peripheral analgesic effects in visceral pain. To evaluate one potential site and mechanism by whichthese effects are produced, we studied opioid effects on high-voltage activated (HVA) Ca2+ currents in identified (Di-I) pelvic nerve sensory neuronsfrom the S1 dorsal root ganglion (DRG). Results were compared with opioid effects on cutaneous neurons from L5 or L6 DRG. Di-I-labeled DRG cells werevoltage clamped (perforated whole cell patch clamp), and HVA Ca2+ currentswere evoked by depolarizing 240-ms test pulses to +10 mV from a holding potential of -60 mV. Neither mu-ORAs (morphine, 10(-6) M, n = 16; [D-Ala(2), N-Me-Phe(4), Gly-ol(5)] enkephalin, 10(-6) M, n = 12) nor delta-ORAs ([D-Pen(2), D-Pen(5)] enkephalin, 10(-7) M, n = 16; SNC-80, 10(-7) M, n = 7) affected HVA Ca2+ currents in colon sensory neurons. In contrast, the kappa-ORAs U50,488 (10(-6) M), bremazocine (10(-6)M), and nalBzoH (10(-6) M) significantly attenuated HVA Ca2+ currents in colon sensory neurons; effects on cutaneous sensory neurons were variable. A nonnceptor selective concentrationof naloxone (10(-5) M) and nor-BNI (10(-6) M), a selective kappa-opioid receptor antagonist, reversed the inhibitory effect of kappa-ORAs. In the presence of N-, P-, or Q-, but not L-type Ca2+ channel antagonists, the effectof U50,488 on HVA Ca2+ currents was significantly reduced. Pretreatment with pertussis toxin (PTX) prevented the inhibition by U50,488. These resultssuggest that kappa-opioid receptors are coupled to multiple HVA Ca2+ channels in colon sensory neurons by a PTX-sensitive G protein pathway. We conclude that inhibition of Ca2+ channel function likely contributes in part to the peripheral analgesic action of kappa-ORAs in visceral nociception.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 05/07/20 alle ore 10:29:22