Fig. 1
Effects of P2X3 stimulation in the dorsolateral PAG on the paw withdrawal potential (PAW) in control rats and STZ rats. A histological section shows the location of the injection cannula track in the PAG (a). An arrow indicates the cannula tract. Scale bar = 0.5 mm. Microinjection of α,β-meATP (50 nmol/µl) into the dorsolateral PAG increased the PAW in control rats (b) and STZ rats (c) compared with aCSF injection. Also, blocking P2X3 with the prior administration of A-317491 (10 nmol/µl) attenuated P2X3-enhanced PAW in both groups. The percentage increase of PAW evoked by stimulation of P2X3 was smaller in STZ rats than in control rats (d). Data are expressed as mean ± SEM. b and c *P < 0.05 vs. aCSF and α,β-meATP with prior injection of A-317491. d *P < 0.05 vs. control rats. The number of control rats = 12; the number of STZ rats = 12