Sprague-Dawley male rats 200-250 g weighting were treated with saline or 0.25-0.5-1.0 mg/Kg risperidone. 125I-epidepride quantitative autoradiography was performed on horizontal entorhinal cortex frozen sections of saline-treated or 1.0 mg/Kg risperidone-treated rats. Tyrosine Hidroxylase (TH) and dopamine transporter (DAT) immunoreactivity as well as western and immuno blotting. 125I-epidepride quantitative autoradiography showed an increasing distribution of D2 dopamine receptors (D2DAR) from medial (MEA) to lateral entorhinal cortex (LEA) in the saline treated rats of both layer I and layer III. Moreover 1 mg/Kg treated rats are characterized by up-regulation of D2DAR that was higher in MEA, and more in the medial half of MEA (MEAm), than in LEA. In the saline-treated rats DAT immunoreactivity was undetectable in MEA as well as in LEA, but all risperidone-treated rats showed low but detectable levels of DAT and DAT-immunoreactive fibers in the layer I as well as in layer III. In detail by immunoblotting was identified a band of 80 KD corresponding to DAT that appeared increased in area and in optical density from 0.25 up to 1.0 mg/Kg risperidone-treated specimens. TH immunoreactivity was detected in nerve fibers mainly located in layers I and III, that showed an increase of optical density higher in MEA than in LEA. Also immunoblotting outlined an increased 60 KD band wider and more dense in specimens treated with highest dose of risperidone. Our data suggested that unhomogeneous distribution of D2DAR, TH and DAT immunoreactivity agree with a further subdivision of MEA in a medial (MEAm) and a lateral (MEAl) portion.
Entorhinal cortex subdivisions: D2 dopamine receptor and dopamine fibers distribution
NICOLARDI, Giuseppe;DE NUCCIO, FRANCESCO;LOFRUMENTO, Dario Domenico
2006-01-01
Abstract
Sprague-Dawley male rats 200-250 g weighting were treated with saline or 0.25-0.5-1.0 mg/Kg risperidone. 125I-epidepride quantitative autoradiography was performed on horizontal entorhinal cortex frozen sections of saline-treated or 1.0 mg/Kg risperidone-treated rats. Tyrosine Hidroxylase (TH) and dopamine transporter (DAT) immunoreactivity as well as western and immuno blotting. 125I-epidepride quantitative autoradiography showed an increasing distribution of D2 dopamine receptors (D2DAR) from medial (MEA) to lateral entorhinal cortex (LEA) in the saline treated rats of both layer I and layer III. Moreover 1 mg/Kg treated rats are characterized by up-regulation of D2DAR that was higher in MEA, and more in the medial half of MEA (MEAm), than in LEA. In the saline-treated rats DAT immunoreactivity was undetectable in MEA as well as in LEA, but all risperidone-treated rats showed low but detectable levels of DAT and DAT-immunoreactive fibers in the layer I as well as in layer III. In detail by immunoblotting was identified a band of 80 KD corresponding to DAT that appeared increased in area and in optical density from 0.25 up to 1.0 mg/Kg risperidone-treated specimens. TH immunoreactivity was detected in nerve fibers mainly located in layers I and III, that showed an increase of optical density higher in MEA than in LEA. Also immunoblotting outlined an increased 60 KD band wider and more dense in specimens treated with highest dose of risperidone. Our data suggested that unhomogeneous distribution of D2DAR, TH and DAT immunoreactivity agree with a further subdivision of MEA in a medial (MEAm) and a lateral (MEAl) portion.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
