Gene expression of synaptosomal-associated protein 25 (SNAP-25) in the prefrontal cortex of the spontaneously hypertensive rat (SHR).
Dopamine is believed to play an important role in the etiology of attention-deficit/hyperactivity disorder (ADHD). In our previous study, we showed that gene expression of dopamine D4 receptor decreased in the spontaneously hypertensive rat (SHR) in the prefrontal cortex (PFC). In the present study, we explored the potential causes of dysfunction in the dopamine system in ADHD. It is the first time that neuronal activities in both juvenile SHR and WKY rats have been measured by functional MRI (fMRI). Our results showed that in PFC the Blood Oxygenation Level Dependent (BOLD) signal response in SHR was much higher than WKY under stressful situations. We tested the effects of acute and repeated administration of amphetamine on behavioral changes in SHR combined with the expression of the neuronal activity marker, c-fos, in the PFC. Meanwhile dopamine-related gene expression was measured in the PFC after repeated administration of amphetamine. We found that potential neuronal damage occurred through deficit of D2-like receptor protective functions in the PFC of the SHR. We also measured the expression of synaptosomal-associated protein 25 (SNAP-25) in SHR in PFC. The results showed decreased expression of SNAP-25 mRNA in the PFC of SHR; this defect disappeared after repeated injection of D-AMP.
Li
Qi
Q
The Department of Psychiatry, Faculty of Medicine, The University of Hong Kong, 21 Sasson Road, Pokfulam, Hong Kong, China.
Wong
Jack H
JH
Lu
Gang
G
Antonio
Gregory E
GE
Yeung
David K
DK
Ng
Tzi B
TB
Forster
Lucy E
LE
Yew
David T
DT
D000662:Amphetamines / Q000494:pharmacology; D000818:Animals; D001289:Attention Deficit Disorder with Hyperactivity / Q000378:metabolism* / Q000503:physiopathology; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D004298:Dopamine / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D009043:Motor Activity / Q000187:drug effects; D017397:Prefrontal Cortex / Q000033:anatomy & histology / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D050825:Synaptosomal-Associated Protein 25 / Q000235:genetics / Q000378:metabolism*
D000662:Amphetamines; D016760:Proto-Oncogene Proteins c-fos; D050825:Synaptosomal-Associated Protein 25; D004298:Dopamine