Bradykinin-induced ion currents in cultured rat trigeminal ganglion cells.
Effects of bradykinin (BK) on membrane currents of cultured rat trigeminal ganglion cells were studied with a G omega-sealed discontinuous voltage clamp technique. Bradykinin (0.05 nM-1 microM) produced membrane depolarization in most cells and hyperpolarization in some cells via a variety of ionic mechanisms: (1) activation of a cation current, (2) enhancement or (3) inhibition of a hyperpolarization-activated inwardly rectifying cation current known as IH, (4) reduction or (5) enhancement of an outwardly rectifying outward current (presumably a delayed K+ current), (6) inhibition of a slow-gating voltage-dependent steady-state outward current (at > -55 mV) and/or (7) increase in another slow-gating voltage-dependent outward current (at > or = -70 mV). These components of BK-induced currents appeared in different combinations and extents among cells, explaining complex excitatory and modulatory actions of BK in different regions and types of sensory neurons.
Kitakoga
O
O
Department of Physiology, Saga Medical School, Japan.
Kuba
K
K
D000818:Animals; D001920:Bradykinin / Q000494:pharmacology*; D002412:Cations / Q000378:metabolism*; D002478:Cells, Cultured; D004553:Electric Conductivity; D006706:Homeostasis; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D012668:Trigeminal Ganglion / Q000166:cytology / Q000502:physiology*
D002412:Cations; D001920:Bradykinin