Decreased locomotor activity in mice carrying transgenic Fyn tyrosine kinase

We found that mice carrying constitutively active Fyn tyrosine kinase show low levels of spontaneous locomotor activity and that this activity increases when the mice are treated with the NMDA receptor antagonist MK-801. These findings indicate that the tyrosine phosphorylation of the NMDA receptors by Fyn participates in the control of locomotor activity.