[Inhibition of GABA-activated currents in isolated rat DRG neurons by bradykinin].
In the present paper, the modulation of GABA-activated currents by bradykinin (BK) was studied in DRG neurons freshly isolated from rat using whole-cell patch-clamp techniques. Among the neurons (n = 34) responding to GABA, 27 were sensitive to BK. Pre-application of BK, eliciting an inward current alone, inhibited GABA-activated current markedly. For example, 10(-6) mol/L BK suppressed GABA-activated current by about 30%. BK shifted the GABA dose-response curve downward obviously and depressed the maximal response to GABA by 1/3 or more while the Kd value was unchanged. The results suggest that BK inhibits GABA-activated current noncompetitively in rat DRG neurons.
Lu
C Y
CY
Research Center of Experimental Medicine, Tongji Medical University, Wuhan 430030.
Si
J Q
JQ
Li
Z W
ZW
D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D001920:Bradykinin / Q000494:pharmacology*; D002469:Cell Separation; D004594:Electrophysiology; D058787:GABA-A Receptor Antagonists; D005727:Ganglia, Spinal / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000502:physiology*
D058787:GABA-A Receptor Antagonists; D011963:Receptors, GABA-A; D001920:Bradykinin; D001640:Bicuculline