Time-dependent involvement of PKA/PKC in contextual memory consolidation.
Rats were implanted bilaterally with cannulae into the dorsal hippocampus and trained in a Pavlovian fear-conditioning paradigm. Four groups of rats were infused intra-cranially with 1-(5'-isoquinolinesulfonyl)-2-methylpiperazine (H7-dihydrochloride), a potent inhibitor of both protein kinase C (PKC) and cAMP-dependent protein kinase (PKA), at different time intervals in order to examine their involvement in the acquisition and consolidation of contextual fear memory. We demonstrate a significant consolidation deficit of long-term contextual fear-conditioning memory that is maximal when PKA and PKC are inhibited at 90 min post-training. These results suggest the existence of a critical time window, during which these enzymes must be activated for the consolidation of long-term memories.
Department of Psychology, Cognitive Neurobiology Institute, University of Utah, Salt Lake City 84112, USA. cogneuro_institute@hotmail.com
Gene V
GV
Wallenstein
David R
DR
Vago
Anne M
AM
Walberer
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / Q000494:pharmacology; D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects / Q000502:physiology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005239:Fear / Q000187:drug effects / Q000502:physiology; D006624:Hippocampus / Q000033:anatomy & histology / Q000187:drug effects / Q000201:enzymology; D017774:Long-Term Potentiation / Q000187:drug effects; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D051381:Rats; D017207:Rats, Sprague-Dawley
D004791:Enzyme Inhibitors; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C