title: [Inhibition of N/OFQ on transient outward potassium currents in acutely dissociated rat cerebral parietal cortical neurons].
abstract: OBJECTIVE
  To study the effect of Nociceptin/orphanin FQ (N/OFQ) on transient outward potassium (I(A)) in rat cerebral cortical neurons and its kinetic mechanism.
  
  
  METHODS
  The effects of N/OFQ on I(A) were investigated by using the whole cell patch clamp technique in acutely dissociated rat cerebral cortical neurons.
  
  
  RESULTS
  (1) At the voltage of + 60 mV, 0.1 micromol/L N/OFQ made I(A) decreased from (5356.1 +/- 361.6) pA to (4113.3 +/- 312.7) pA (P < 0.01, n = 10) and the percent inhibition was 23.2% +/- 2.2%. (2) (N/OFQ made I-V curve of I(A) decreased significantly (P < 0.01, n = 10).(3) 0.1 micromol/L N/OFQ shifted the activation curve of I(A) to positive potential from (-9.2 +/- 2.5)mV to (30.6 +/- 3.7) mV (P < 0.01, n = 8) and changed the slope factor(kappa) of the activation curve from (20.4 +/- 2.3) mV to (22.6 +/- 2.1) mV (P > 0.05, n = 8). (4) 0.1 micromol/L N/OFQ caused a significant hyperpolarizing shift of the inactivation curve from (-64.1 +/- 3.2) mV to (-55.9 +/- 1.9) mV (P < 0.05, n = 5), without significant effect on kappa of the inactivation curve.
  
  
  CONCLUSIONS
  0.1 micromol/L N/OFQ has a significant inhibition on I(A) and shift the activation and inactivation curve to depolarization in cerebral parietal cortical neurons of rats.
authors.affiliation: Department of Physiology, Harbin Medical University, Harbin 150081, China.
authors.forename: Li-Hui
authors.initials: LH
authors.lastname: Qu
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Xu
authors.initials: X
authors.lastname: Yang
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.forename: Xue-Yi
authors.initials: XY
authors.lastname: Liu
authors.forename: Hong-Bo
authors.initials: HB
authors.lastname: Jin
authors.forename: Yu-Rong
authors.initials: YR
authors.lastname: Li
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D005260:Female; D008297:Male; D009474:Neurons / Q000502:physiology; D018847:Opioid Peptides / Q000502:physiology*; D010296:Parietal Lobe / Q000502:physiology*; D026902:Potassium Channel Blockers; D015221:Potassium Channels / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D000097629:Nociceptin
chemical_list: D018847:Opioid Peptides; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D000097629:Nociceptin