Signaling by ATP receptors in astrocytes.
Treatment of primary cultures of rat cerebral cortical astrocytes with extracellular ATP caused a 3- to 4-fold stimulation of mitogen-activated protein (MAP) kinase activity. Studies with agonists and antagonists of P1 and P2 purinergic receptors indicated that this activation is mediated by ATP/P2 purinergic receptors rather than adenosine/P1 purinergic receptors. Increased cAMP levels did not significantly inhibit the activation of MAP kinase by ATP but did inhibit the stimulation of MAP kinase by basic fibroblast growth factor, a polypeptide growth factor that activates the Ras/Raf kinase signaling pathway. These data indicate that ATP/P2 purinergic receptors are coupled to MAP kinase by a signal transduction pathway that is independent of the Raf kinase pathway.
Neary
J T
JT
Laboratory of Neuropathology, VA Medical Center, Miami, FL 33125.
Zhu
Q
Q
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000502:physiology*; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000096:biosynthesis; D002478:Cells, Cultured; D004789:Enzyme Activation / Q000187:drug effects; D005911:Gliosis / Q000503:physiopathology; D011233:Precipitin Tests; D051381:Rats; D018047:Receptors, Purinergic P1 / Q000187:drug effects; D018048:Receptors, Purinergic P2 / Q000187:drug effects / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*
D018047:Receptors, Purinergic P1; D018048:Receptors, Purinergic P2; D000255:Adenosine Triphosphate; D017871:Calcium-Calmodulin-Dependent Protein Kinases