Signaling of lysophosphatidic acid-evoked chloride current: calcium release from inositol trisphosphate-sensitive store.
In Xenopus oocytes, lysophosphatidic acid (LPA) evoked inward currents at the holding potential of -60 mV, which were quickly desensitized upon repeated challenges of the compound at 10 nM or 1 microM. This desensitization was prevented by pretreatment with protein kinase A inhibitor or recovered by its post-treatment, but not by the pretreatment with an inhibitor of protein kinase C or calmodulin kinase II. From pharmacological studies, the LPA-evoked currents were found to be mediated by phospholipase C, calcium-mobilization from thapsigargin-sensitive Ca2+ stores, araguspongine E-sensitive inositol trisphosphate receptor, and calcium-dependent chloride channels.
Kakizawa
K
K
Department of Molecular Pharmacology and Neuroscience, Nagasaki University, School of Pharmaceutical Sciences, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
Nomura
H
H
Yoshida
A
A
Ueda
H
H
D000818:Animals; D020013:Calcium Signaling / Q000187:drug effects*; D002712:Chlorides / Q000378:metabolism*; D007295:Inositol Phosphates / Q000494:pharmacology*; D008246:Lysophospholipids / Q000494:pharmacology*; D009865:Oocytes; D018408:Patch-Clamp Techniques; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology; D014982:Xenopus laevis
D002712:Chlorides; D007295:Inositol Phosphates; D008246:Lysophospholipids