The effect of CNTF on glutamate-induced increases in intracellular free Ca2+ in hippocampal neurons.
Ciliary neurotrophic factor (CNTF) acts through the JAK/STAT signal transduction pathway. However, the rapid action of CNTF cannot readily be explained by reference to this pathway. Using the fluorophore, Fura 2-AM, and fluorescence imaging, the effect of CNTF on glutamate-induced increases in hippocampal intraneuronal free Ca2+ ([Ca2+]i) was investigated. Glutamate induces a rapid increase in [Ca2+]i. Incubation of hippocampal neurons with CNTF for 5 min inhibited the glutamate-induced increase in [Ca2+]i. In the absence of glutamate, CNTF had no effect on [Ca2+]i. Pertussis toxin (PTX), a G-protein antagonist, partially blocked the effect of CNTF. This suggests that CNTF may act via an alternative signal transduction pathway besides the generic JAK/STAT pathway.
Yan
J
J
Department of Neurobiology, Second Military Medical University, Shanghai, China.
He
C
C
Wang
X Q
XQ
Bao
X
X
Ni
W J
WJ
Lu
C L
CL
D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D020934:Ciliary Neurotrophic Factor / Q000494:pharmacology*; D018698:Glutamic Acid / Q000494:pharmacology*; D006624:Hippocampus / Q000502:physiology*; D007424:Intracellular Fluid / Q000187:drug effects / Q000502:physiology; D007700:Kinetics; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D037342:Pertussis Toxin; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D020934:Ciliary Neurotrophic Factor; D010566:Virulence Factors, Bordetella; D018698:Glutamic Acid; D037342:Pertussis Toxin; D002118:Calcium