关键词: ATP, ReactiveBlue2, POAH, 体温调节

Abstract: Adenosine triphosphate (ATP) is a kind of purinergic neurotransmitter. By means of intraperitoneal injection, intrapreoptical microinjection and Neuronal study of preoptic area of hypothalamic (POAH) tissue slice, effects of ATP on thermoregulation in the rat were investigated. The results are as follows. (1) there occurred an appreciable hypothermia followed by intraperitoneal injection of ATP with dose-dependent effect. Pindolol, a noradrenaline-β receptor antagonist, abolished the effect and suggested that the Tb fall was presumptively mediated by sympathetic nervous system; (2) Intrapreoptical administration of ATP with lower concentration decreased the body temperature, but the effect could be dramatically eliminated by reactive blue 2, a nonselective P₂-purinoceptor antagonist, hinting the likelihood that purinoceptors play an important role in thermoregulation; The higher doses, however, elicited the body temperature rise, which might be attributed to the chelating effect of ATP on free extracellular calcium; (3) The effects of ATP on the warm-sensitive neurons in POAH slices gave further evidence for the result showed in vivo, the higher and lower concentrations of ATP inhibited and facilitated the spontaneous firing of warm-sensitive neurons respectively, which suggested that ATP involved in thermoregulation by direct affecting the warm-sensitive neuron activity in POAH.

Key words: ATP, Reactive Blue 2, POAH, thermoregulation