ISSN:
1471-4159
Quelle:
Blackwell Publishing Journal Backfiles 1879-2005
Thema:
Medizin
Notizen:
Inositol 1,4,5-trisphosphate (InsP3) receptor immunoreactivity in SH-SY5 Y human neuroblastoma cells was monitored with a monoclonal antibody raised against the mouse cerebellar InsP3 receptor. Recognition of a protein corresponding to the InsP3 receptor (molecular mass, ∼275 kDa) was inhibited markedly following exposure of cells to 0.1 mM carbachol. This effect was half-maximal and maximal at ∼2 and ∼6 h, respectively; was blocked by atropine; but was not mimicked by thapsigargin, K+, or phorbol 12-myristate 13-acetate. However, the decrease in immunoreactivity following exposure of cells to carbachol for 5 h was blocked if the extracellular Ca2+ concentration was reduced from 1.3 mM to 200 nM. This manipulation also reduced markedly carbachol-induced increases in InsP3 concentration at 5 h. These data indicate that chronic muscarinic stimulation of phosphoinositide hydrolysis reduces InsP3 receptor concentration in SH-SY5 Y cells, perhaps via a mechanism that involves prolonged elevation of InsP3 levels.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1111/j.1471-4159.1992.tb08916.x
