Differential effects of a selective dopamine D1-like receptor agonist on motor activity and c-fos expression in the frontal-striatal circuitry of SHR and Wistar-Kyoto rats

被引:0
作者
Diaz Heijtz R. [1 ,2 ]
Castellanos F.X. [2 ]
机构
[1] Department of Psychiatry, New York University School of Medicine, New York VA Medical Center, New York, NY 10010
[2] New York University Child Study Center, New York, NY 10016
关键词
Nucleus Accumbens; Piriform Cortex; Olfactory Tubercle; Standard Saline Citrate; Agranular Insular Cortex;
D O I
10.1186/1744-9081-2-18
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摘要
Background: Molecular genetic studies suggest the dopamine D1 receptor (DIR) may be implicated in attention-deficit/hyperactivity disorder (ADHD). As little is known about the potential motor role of DIR in ADHD, animal models may provide important insights into this issue. Methods: We investigated the effects of a full and selective DIR agonist, SKF-81297 (0.3, 3 and 10 mg/kg), on motor behaviour and expression of the plasticity-associated gene, c-fos, in habituated young adult male Spontaneously Hypertensive Rats (SHR), the most commonly used animal model of ADHD, and Wistar-Kyoto (WKY; the strain from which SHR were derived). Results: SHR rats were more behaviourally active than WKY rats after injection with vehicle. The 0.3 mg/kg dose of SKF-81297 increased motor behaviour (locomotion, sifting, rearing, and sniffing) in both SHR and WKY rats. Total grooming was also stimulated, but only in WKY rats. The same dose increased c-fos mRNA expression in the piriform cortex of both strains. The 3 mg/kg dose increased sifting and sniffing in both strains. Locomotion was also stimulated towards the end of the testing period. The intermediate dose decreased total rearing in both strains, and produced a significant increase in c-fos mRNA in the striatum, nucleus accumbens, olfactory tuberculum, and in the cingulate, agranular insular and piriform cortices. The 10 mg/kg dose of SKF-81297 produced a biphasic effect on locomotion, which was characterized by an initial decrease followed by later stimulation. The latter stimulatory effect was more pronounced in SHR than in WKY rats when compared to their respective vehicle-injected groups. The 10 mg/kg dose also stimulated sifting and sniffing in both strains. Both the 3 and 10 mg/kg doses had no effect on total grooming. The 10 mg/kg dose induced significantly higher levels of c-fos mRNA expression in the nucleus accumbens and adjacent cortical regions (but not striatum) of SHR when compared to WKY rats. Conclusion: The present results suggest a potential alteration in DIR neurotransmission within the frontal-striatal circuitry of SHR involved in motor control. These findings extend our understanding of the molecular alterations in SHR, a heuristically useful model of ADHD. © 2006 Heijtz and Castellanos; licensee BioMed Central Ltd.
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共 41 条
[1]  
Castellanos F.X., Tannock R., Neuroscience of attention-deficit/hyperactivity disorder: The search for endophenotypes, Nat Rev Neurosci, 3, pp. 617-628, (2002)
[2]  
Volkow N.D., Wang G.J., Fowler J.S., Ding Y.S., Imaging the effects of methylphenidate on brain dopamine: New model on its therapeutic actions for attention-deficit/hyperactivity disorder, Biol Psychiatry, 57, pp. 1410-1415, (2005)
[3]  
Faraone S.V., Perlis R.H., Doyle A.E., Smoller J.W., Goralnick J.J., Holmgren M.A., Sklar P., Molecular genetics of attention-deficit/hyperactivity disorder, Biol Psychiatry, 57, pp. 1313-1323, (2005)
[4]  
Missale C., Nash S.R., Robinson S.W., Jaber M., Caron M.G., Dopamine receptors: From structure to function, Physiol Rev, 78, pp. 189-225, (1998)
[5]  
Arnsten A.F., Li B.M., Neurobiology of executive functions: Catecholamine influences on prefrontal cortical functions, Biol Psychiatry, 57, pp. 1377-1384, (2005)
[6]  
Chudasama Y., Robbins T.W., Functions of frontostriatal systems in cognition: Comparative neuropsychopharmacological studies in rats, monkeys and humans, Biol Psychol, (2006)
[7]  
Bobb A.J., Addington A.M., Sidransky E., Gornick M.C., Lerch J.P., Greenstein D.K., Clasen L.S., Sharp W.S., Inoff-Germain G., Wavrant-De V.F., rcos-Burgos M., Straub R.E., Hardy J.A., Castellanos F.X., Rapoport J.L., Support for association between ADHD and two candidate genes: NET1 and DRD1, Am J Med Genet B Neuropsychiatr Genet, 134, pp. 67-72, (2005)
[8]  
Misener V.L., Luca P., Azeke O., Crosbie J., Waldman I., Tannock R., Roberts W., Malone M., Schachar R., Ickowicz A., Kennedy J.L., Barr C.L., Linkage of the dopamine receptor D1 gene to attention-deficit /hyperactivity disorder, Mol Psychiatry, 9, pp. 500-509, (2004)
[9]  
Laurin N., Misener V.L., Crosbie J., Ickowicz A., Pathare T., Roberts W., Malone M., Tannock R., Schachar R., Kennedy J.L., Barr C.L., Association of the calcyon gene (DRDIIP) with attention deficit /hyperactivity disorder, Mol Psychiatry, 10, pp. 1117-1125, (2005)
[10]  
Papa M., Diewald L., Carey M.P., Esposito F.J., Gironi Carnevale U.A., Sadile A.G., A rostro-caudal dissociation in the dorsal and ventral striatum of the juvenile SHR suggests an anterior hypo- and a posterior hyperfunctioning mesocorticolimbic system, Behav Brain Res, 130, pp. 171-179, (2002)