Mediation of hippocampal mossy fiber long-term potentiation by cyclic AMP.
Repetitive activation of hippocampal mossy fibers evokes a long-term potentiation (LTP) of synaptic responses in pyramidal cells in the CA3 region that is independent of N-methyl-D-aspartate receptor activation. Previous results suggest that the site for both the induction and expression of this form of LTP is presynaptic. Experimental elevation of cyclic adenosine 3',5'-monophosphate (cAMP) both mimics and interferes with tetanus-induced mossy fiber LTP, and blockers of the cAMP cascade block mossy fiber LTP. It is proposed that calcium entry into the presynaptic terminal may activate Ca(2+)-calmodulin-sensitive adenylyl cyclase I which, through protein kinase A, causes a persistent enhancement of evoked glutamate release.
Weisskopf
M G
MG
Neuroscience Graduate Program, University of California, San Francisco 94143-0450.
Castillo
P E
PE
Zalutsky
R A
RA
Nicoll
R A
RA
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002227:Carbazoles; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D005971:Glutamates / Q000378:metabolism / Q000494:pharmacology; D018698:Glutamic Acid; D006168:Guinea Pigs; D006624:Hippocampus / Q000502:physiology*; D066298:In Vitro Techniques; D007211:Indoles / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D017774:Long-Term Potentiation / Q000187:drug effects; D008954:Models, Biological; D009412:Nerve Fibers / Q000502:physiology*; D017729:Presynaptic Terminals / Q000378:metabolism; D017966:Pyramidal Cells / Q000502:physiology; D011758:Pyrroles / Q000494:pharmacology; D013449:Sulfonamides; D009435:Synaptic Transmission / Q000187:drug effects
D002227:Carbazoles; D005971:Glutamates; D007211:Indoles; D007546:Isoquinolines; D011758:Pyrroles; D013449:Sulfonamides; D005576:Colforsin; D018698:Glutamic Acid; C057416:KT 5720; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide; D002118:Calcium