title: Somatostatin increases rat locomotor activity by activating sst(2) and sst (4) receptors in the striatum and via glutamatergic involvement.
abstract: The involvement of striatal somatostatin receptors (sst(1), sst(2) and sst(4)) in locomotor activity was investigated. Male Sprague-Dawley rats, 280-350 g, received in the striatum bilateral infusions of saline, somatostatin, and selective sst(1), sst(2), and sst(4) ligands. Spontaneous locomotor activity was recorded for 60 min. The involvement of excitatory amino acid receptors (AMPA and NMDA) on somatostatin's actions was also examined. Western blot analysis was employed for the identification of somatostatin receptors in striatal membranes. Somatostatin, sst(2) and sst(4), but not sst(1), selective ligands increased rat locomotor activity in a dose-dependent manner. Blockade of AMPA and NMDA receptors reversed somatostatin's actions. In conclusion, striatal somatostatin receptor activation differentially influence rat locomotor activity, while glutamatergic actions underlie the behavioral actions of somatostatin.
authors.affiliation: Department of Basic Sciences, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece.
authors.forename: Stratos
authors.initials: S
authors.lastname: Santis
authors.forename: Andreas
authors.initials: A
authors.lastname: Kastellakis
authors.forename: Dimitra
authors.initials: D
authors.lastname: Kotzamani
authors.forename: Kalliopi
authors.initials: K
authors.lastname: Pitarokoili
authors.forename: Despoina
authors.initials: D
authors.lastname: Kokona
authors.forename: Kyriaki
authors.initials: K
authors.lastname: Thermos