Critical role for GALR1 galanin receptor in galanin regulation of neuroendocrine function and seizure activity.

The GALR1 galanin receptor is expressed at high levels within the central nervous system. To determine which specific actions of galanin are mediated by GALR1, we have developed mice with an insertional inactivating mutation within the gene encoding GALR1 (Galr1). Homozygous Galr1-/- mice are viable and capable of breeding. They exhibit no significant difference in growth rate relative to Galr1+/+ controls but have reduced circulating levels of insulin-like growth factor-I (IGF-I) and exhibit spontaneous tonic-clonic seizures. The phenotype of these mice identifies a critical role for GALR1 in neuroendocrine regulation and in mediating the anti-seizure activity of galanin.