GABA_A receptor partially mediated propofol-induced hyperalgesia at ventrolateral periaqueductal gray(vlPAG) of rats / 中国药理学通报

ABSTRACT

Aim To observe the effects of propofol on nociceptive response at ventrolateral periaqueductal gray(vlPAG) of rats and the possible role of GABA_A receptor in this prosses.Methods Sprague-Dawley(SD) female rats were randomized into each group.Bicuculline and propofol were microinjected into ventrolateral periaqueductal gray(vlPAG).The noxious response was evaluated by hot plate and formalin test.Fos-like immunoreactivity(FLI) neurons expressed in spinal dorsal horn(DH) induced by formalin intraplantar injection(sc) of one hindpaw were used as a neuroactive marker to observe the effects of propofol on the noxious transmission in DH.Results In hot-plate test,the hyperalgesia induced by propofol(10 g?L~(-1)) vlPAG microinjection was significantly antagonized about(70%),(71%) at 10 and 20 min after (bicu-)culline(25 mg?L~(-1)) vlPAG microinjection(P