Social learning and amygdala disruptions in Nf1 mice are rescued by blocking p21-activated kinase.

Children with neurofibromatosis type 1 (NF1) are increasingly recognized as having a high prevalence of social difficulties and autism spectrum disorders (ASDs). We demonstrated a selective social learning deficit in mice with deletion of a single Nf1 allele (Nf1(+/-)), along with greater activation of the mitogen-activated protein kinase pathway in neurons from the amygdala and frontal cortex, structures that are relevant to social behaviors. The Nf1(+/-) mice showed aberrant amygdala glutamate and GABA neurotransmission, deficits in long-term potentiation and specific disruptions in the expression of two proteins that are associated with glutamate and GABA neurotransmission: a disintegrin and metalloprotease domain 22 (Adam22) and heat shock protein 70 (Hsp70), respectively. All of these amygdala disruptions were normalized by the additional deletion of the p21 protein-activated kinase (Pak1) gene. We also rescued the social behavior deficits in Nf1(+/-) mice with pharmacological blockade of Pak1 directly in the amygdala. These findings provide insights and therapeutic targets for patients with NF1 and ASDs.