Long-term potentiation is mediated by multiple kinase cascades involving CaMKII or either PKA or p42/44 MAPK in the adult rat dentate gyrus in vitro.
The induction of NMDA-receptor-dependent long-term potentiation (LTP) in adult CA1 is contingent on activation of Ca/calmodulin-dependent protein kinase II (CaMKII). However, little is known about kinase mediation of LTP in the dentate gyrus. In the present study, the involvement of the kinases CaMKII, PKA, and MAPK in the induction of LTP was studied in the dentate gyrus of adult rats. Individual application of selective inhibitors of CaMKII, MEK, or PKA did not inhibit induction of LTP. In contrast, coapplication of a CaMKII inhibitor with either a PKA or MEK inhibitor resulted in a strong block of LTP. Induction of LTP was blocked by the coapplication of the inhibitors CaMKII and PKA or MEK, both when they were applied 1 h before the induction stimulus and also when they were applied after the induction stimulus. Thus LTP is mediated by either of two parallel cascades, one involving CaMKII and the other PKA or MAPK. Moreover, these cascades are active for a certain period after the induction stimulus.
Wu
Jianqun
J
Department of Physiology, Trinity College, Dublin 2, Ireland.
Rowan
Michael J
MJ
Anwyl
Roger
R
D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D018891:Dentate Gyrus / Q000502:physiology*; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000502:physiology*; D020935:MAP Kinase Signaling System / Q000502:physiology*; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D009097:Multienzyme Complexes / Q000378:metabolism; D051381:Rats
D009097:Multienzyme Complexes; D017868:Cyclic AMP-Dependent Protein Kinases; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3