Intracellular cAMP regulates the response to NMDA in hippocampal neurons.
We have studied the effects of intracellular cyclic AMP (cAMP) on the response to N-methyl-D-aspartate (NMDA) in hippocampal cultured neurons by loading them with 2'-o-dibutyryladenosine 3', 5'-cyclic monophosphate (dcAMP) and have obtained evidence for regulation of Ca2+ release from intracellular stores by cAMP. Extracellular Ringer's solution was either Ca(2+)-containing or Ca(2+)-free. A brief initial stimulation with NMDA (10-100 microM, 12 s) was required before the neurons were loaded with dcAMP to potentiate the changes in intracellular Ca2+ concentration induced by the second stimulus of NMDA. Forskolin (10 microM) mimicked dcAMP, but to a lesser extent. A phorbol ester 12-o-tetradecanoylphorbol-13-acetate (100 nM) inhibited the effect of dcAMP.
Harada
K
K
Department of Neurosurgery and Pharmacology, School of Medicine, Yamaguchi University, Ube, Japan.
Nagatsugu
Y
Y
Ito
H
H
Shingai
R
R
D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000502:physiology*; D004789:Enzyme Activation / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects*; D016202:N-Methylaspartate / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects; D011493:Protein Kinase C / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D005576:Colforsin; D016202:N-Methylaspartate; D003994:Bucladesine; D000242:Cyclic AMP; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium