Traumatic brain injury reduces dopamine transporter protein expression in the rat frontal cortex

Abstract

Disturbances in dopamine neurotransmission contribute to frontal lobe dysfunction after traumatic brain injury. The changes in dopamine neurotransmission may be mediated by alterations in the dopamine transporter, which plays a key role in maintaining dopamine homeostasis. To determine whether the dopamine transporter system is altered after traumatic brain injury, dopamine transporter protein was examined bilaterally in the rat frontal cortex by Western blot at 1, 7, and 28 days after controlled cortical impact or sham injury ( = 6/group). Dopamine transporter protein expression was decreased in the injured (ipsilateral) cortex at 7 days and bilaterally at 28 days in injured sham control rats. The decrease in dopamine transporter protein levels may reflect a traumatic brain-injury-induced down-regulation of dopamine transporter and/or a loss of dopaminergic fibers.

Delayed increase of tyrosine hydroxylase expression in rat nigrostriatal system after traumatic brain injury

“…These time points were selected on basis of previous studies of DA systems after TBI (Yan et al, 2001(Yan et al, , 2002. Tissue preparation and immunohistochemistry procedures were as previously reported (Yan et al, 2001).…”

Rehabilitation Considerations for Traumatic Brain Injury in the Geriatric Population: Epidemiology, Neurobiology, Prognosis, and Management

“…Following TBI, there are changes in CNS-DA levels secondary to multiple mechanisms [56,57]. Long-term changes in DA transporter (DAT) expression, as well as changes in other DA system proteins, are seen within the cortex and striatum [58][59][60]. This is accompanied by changes in postsynaptic secondary signaling mechanisms and presynaptic DA synthetic enzymes following TBI [61].…”

“…This is accompanied by changes in postsynaptic secondary signaling mechanisms and presynaptic DA synthetic enzymes following TBI [61]. The concentration of DAT within the basal ganglia declines as a normal course of aging, and in a more accelerated fashion in PD, while DAT is the most important factor determining concentrations of extra-neural dopamine as well as its duration of action [60]. A reduction in DAT availability expression that occurs following a TBI has some similarities to that observed in PD, but may also be a compensatory response to augment DA transmission [60].…”

Effects of Nicotine Administration on Striatal Dopamine Signaling after Traumatic Brain Injury in Rats

“…Animal models demonstrated alterations in proteins regulating the dopamine system (Yan et al, 2001(Yan et al, , 2002(Yan et al, , 2007 as well as electrically induced dopamine release and uptake after TBI (Wagner et al, 2005). Our recently reported study demonstrated the decrease in the activity of tyrosine hydroxylase (TH) and corresponding dopamine release in the striatum of rats 1 week after TBI (Shin et al, 2011).…”