Long-term potentiation and spatial learning are associated with increased phosphorylation of TrkB and extracellular signal-regulated kinase (ERK) in the dentate gyrus: evidence for a role for brain-derived neurotrophic factor.
In this study, the authors investigate changes in the presynaptic terminal of the dentate gyrus that accompany 2 types of hippocampal-dependent plasticity: spatial learning and long-term potentiation (LTP). Parallel changes occurred in the dentate gyrus of rats that had undergone training in the Morris water maze and had sustained LTP. In both cases, KCl-induced brain-derived neurotrophic factor release was increased, and this was accompanied by increased phosphorylation of TrkB and the mitogen-activated protein kinase, ERK. Glutamate release was also enhanced, and the data suggest that this may be a consequence of increased activation of TrkB and ERK. Because the data indicate that similar cellular modifications are shared by these 2 forms of plasticity, they provide circumstantial evidence that LTP satisfies some of the requirements of a memory-inducing cellular substrate.
Gooney
M
M
Department of Physiology, Trinity College, Dublin, Ireland.
Shaw
K
K
Kelly
A
A
O'Mara
S M
SM
Lynch
M A
MA
D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000096:biosynthesis / Q000378:metabolism* / Q000502:physiology; D018891:Dentate Gyrus / Q000378:metabolism*; D007858:Learning / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology*; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar; D020813:Receptor, trkB / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D013037:Spatial Behavior / Q000502:physiology
D019208:Brain-Derived Neurotrophic Factor; D020813:Receptor, trkB; D020928:Mitogen-Activated Protein Kinases