Objective
Brain ischemia is considered an extremely potent stress factor at the cellular and molecular level which may lead to massive neuronal death. Alternatively, short brain ischemia and reperfusion (I/R) can actually stimulate neurogenesis, angiogenesis and peptidergic signaling. There is little known about the potential effect of I/R on brain expression of the novel neuropeptide; phoenixin (PNX) and its receptor GPR173.

Methods
The study was carried out on adult male Wistar rats divided into seven groups: control, sham operation and 5 ischemic experimental groups across the time course of reperfusion. We examined mRNA and protein expression of GPR173 and neurogenesis markers Musashi-1, doublecortin (DCX), and Sox-2 in the striatum.

Results
GPR-173 positive cells were found only in the ischemic hemisphere, where Musashi-1, DCX and Sox-2-positive cells were also observed. Gene expression analysis also showed a significant increase of GPR-173 mRNA level in the I/R striatum in comparison with the control one. Results confirm previous findings suggesting that I/R stimulates adult neurogenesis in the striatum and affects peptidergic signaling in this structure.

Conclusions
A very fast occurence of GPR-173 expression revealed in the striatum may potentially be exclusively related to neuroprotective neurochemical changes that occur in this region after I/R.