Tyrosine kinase inhibitors impair long-term memory formation in day-old chicks

The involvement of protein kinases in numerous neuronal cellular processes, including learning and memory, has been well established, particularly regarding serine/threonine kinases. In the present study, the role of protein kinases in learning was further examined through an investigation of the effects of inhibitors of tyrosine kinase activity on memory formation. The present findings reveal that the intracranial administration of the tyrosine kinase inhibitors genistein and lavendustin A produced retention deficits in day-old chicks trained on a single-trial passive avoidance task. These deficits were not apparent until 90 min after the training episode and were not observed at all in chicks administered control substances. The possibility that the tyrosine phosphorylation disrupted by the presence of the inhibitors is related to NMDA glutamate receptor activation is considered.