caa a22 4500 397581947 CHVBK 20180308164909.0 cr unu---uuuuu 161202e199607 xx s 000 0 eng 10.1093/cercor/6.4.561 doi (NATIONALLICENCE)oxford-10.1093/cercor/6.4.561 Induction of c-fos mRNA in Rat Medial Prefrontal Cortex by Antipsychotic Drugs: Role of Dopamine D2 and D3 Receptors [Elektronische Daten] [Kalpana M. Merchant, Lana M. Figur, Dawna L. Evans] The present studies compared the effects of acute and chronic administration of haloperidol or clozapine on c-fos mRNA expression in the rat medial prefrontal cortex. Acute administration of clozapine, but not haloperidol, robustly increased c-fos mRNA expression in the infralimbic and prelimbic cortex of the rat. Even though most c-fos mRNA-expressing neurons in the clozapine-treated animals were localized in deep cortical layers, labeled neurons were found organized into several cell bridges connecting the superficial and deep layers of the cortex. After chronic treatment with clozapine, c-fos mRNA was reduced by−60% of that seen acutely; however, the columns of c-fos mRNA expressing neurons did not show the same magnitude of tolerance. Haloperidol had no significant effect even after chronic treatment. We examined further the role of dopamine D2 versus D3 receptors in c-fos gene induction in the infralimbic cortex by studying the acute effects of remoxipride and U-99194A. Remoxipride, a selective D2 antagonist in vitro, induced c-fos mRNA at very low doses and lost its ability to alter c-fos mRNA levels at higher doses. Interestingly, U-991 94A, an antagonist with 20-fold selectivity for D3 over D2 receptors, also produced greater induction of c-fos mRNA at lower doses. We hypothesize that blockade of D3 receptors may enhance c-fos gene expression in the medial prefrontal cortex but that of D2 receptors may prevent the same. © 1996 Oxford University Press Articles nationallicence Merchant Kalpana M. CNS Diseases Research, Upjohn Laboratories, 301 Henrietta Street, Kalamazoo, MI 49001, USA aut Figur Lana M. CNS Diseases Research, Upjohn Laboratories, 301 Henrietta Street, Kalamazoo, MI 49001, USA aut Evans Dawna L. CNS Diseases Research, Upjohn Laboratories, 301 Henrietta Street, Kalamazoo, MI 49001, USA aut Cerebral Cortex Oxford University Press 6/4(1996-07), 561-570 1047-3211 6:4<561 1996 6 cercor https://doi.org/10.1093/cercor/6.4.561 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1093/cercor/6.4.561 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Merchant Kalpana M. CNS Diseases Research, Upjohn Laboratories, 301 Henrietta Street, Kalamazoo, MI 49001, USA aut NATIONALLICENCE 700 1- Figur Lana M. CNS Diseases Research, Upjohn Laboratories, 301 Henrietta Street, Kalamazoo, MI 49001, USA aut NATIONALLICENCE 700 1- Evans Dawna L. CNS Diseases Research, Upjohn Laboratories, 301 Henrietta Street, Kalamazoo, MI 49001, USA aut NATIONALLICENCE 773 0- Cerebral Cortex Oxford University Press 6/4(1996-07), 561-570 1047-3211 6:4<561 1996 6 cercor Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford