Evidence for a modulatory effect of sulbutiamine on glutamatergic and dopaminergic cortical transmissions in the rat brain

Chronic treatment of rats by sulbutiamine induced no change in density of N -methyl-D-aspartate (NMDA) and (+/-)-alpha-amino-3-hydroxy-5-methylisoxazol e-4-propionic acid receptors in the cingular cortex, but a significant decr ease of the kainate binding sites, as measured by quantitative autoradiogra phy. In the same treated animals, an increase of D1 dopaminergic (DA) bindi ng sites was measured both in the prefrontal and the cingular cortex, while no modification of the D2 binding sites was detected. Furthermore, an acut e sulbutiamine administration induced a decrease of kainate binding sites b ut no change of the density of D1 and D2 DA receptors. Acute sulbutiamine i njection led to a decrease of he DA levels in the prefrontal cortex and 3,4 -dihydroxyphenylacetic acid levels in both the cingular and the prefrontal cortex. These observations are discussed in terms of a modulatory effect of sulbutiamine on both dopaminergic and glutamatergic cortical transmissions . (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.