Effects of endocrine disrupter chemicals on a novel G-protein-coupled neurosteroid receptor

足底注射脱氢表雄酮硫酸盐(DHEAS)是一种典型的神经类固醇，在Hargreaves‘s热或自动爪压机械痛觉试验中显示出痛敏反应。组胺(His)H_1受体拮抗剂苯海拉明(DPH)可阻断DHEAS引起的痛敏反应，也可阻断His或肥大细胞脱颗粒药化合物48/80所引起的痛敏反应。DHEAS诱导的痛敏也可被孕酮(PROG)阻断，孕酮是另一种神经类固醇，可能是一种神经类固醇受体拮抗剂。DPH和PROG在温度阈值上都没有显示任何变化。在致痛基因诱导的小鼠屈肌伤害性反应实验中，足底注射DHEAS引起的屈肌反应可被内分泌干扰物(EDC)p，p‘-DDE和PROG阻断。在Hargreaves热痛觉实验中，p，p‘-DDE也能阻断DHEAS引起的痛敏反应。除痛觉过敏作用外，DHEAS还可增加血管PE-…用伊文思蓝血浆外渗法测量更多的可测性。与行为学研究一致，它被DPH、PROG和p，p‘-DDE阻断。这些结果表明，DHEAS通过释放His具有明显的痛觉过敏和血管扩张作用，这些作用可被Prog和EDC，p，p‘-DDE逆转。此外，我们证明了一种新的神经类固醇受体的存在和特征，这种新的神经类固醇受体支持这种快速的促过敏作用。在肥大细胞系RBL-2H3释放β-氨基己糖苷酶的测定中，包括DHEAS在内的一些激动型神经类固醇引起迅速脱颗粒，并被Prog阻断。药理分析表明，可能的膜受体刺激导致新的G_&lt；Q/11&gt；和磷脂酶C激活，随后[Ca^&lt；2+&gt；]_i升高。我们进一步发现，许多具有代表性的EDCs对DHEAS诱导的[Ca~(2+)]_i升高、脱颗粒和伤害性反应具有拮抗作用。这些结果提示，G_&lt；q/11&gt；偶联的神经类固醇受体可能调节与感觉刺激相关的神经免疫活性，而内分泌细胞可能通过这种机制的紊乱而发挥神经作用。较少

The intraplantar injection of dehydroepiandrosterone sulfate (DHEAS), a representative neurosteroid, showed hyperalgesia in the Hargreaves' thermal or automatic paw-pressure mechanical nociception test. The Diphenhydramine (DPH), an H_1 histamine (His) receptor antagonist, blocked the hyperalgesia induced by DHEAS as well as the hyperalgesia induced by His or compound 48/80, a mast cell degranulating agent. The DHEAS-induced hyperalgesia was also blocked by progesterone (PROG), another type of neurosteroid and a putative neurosteroid receptor antagonist. Neither DPH nor PROG showed any changes in the thermal threshold. In the algogenics-induced nociceptive flexor responses test in mice, the flexor responses induced by intraplantar injection of DHEAS were blocked by p,p'-DDE, an endocrine disrupting chemical (EDC) as well as by PROG. P,p'-DDE also blocked the DHEAS-induced hyperalgesia in Hargreaves' thermal nociception test. Besides the hyperalgesic actions, DHEAS increased vascular pe … More rmeability as measured with Evans blue plasma extravasation. Consistent with behavioral studies, it was blocked by DPH, PROG and p,p'-DDE. These results suggest that DHEAS has significant hyperalgesic and vasodilatory actions through His release, and these actions were reversible by PROG and an EDC, p,p'-DDE. Moreover, we demonstrated the presence and characterization of a novel neurosteroid receptor underlying such rapid algogenic actions. In the measurements of β-hexosaminidase release from a mast cell line, RBL-2H3, some agonistic neurosteroids, including DHEAS caused rapid degranulation, and it was blocked by PROG. Pharmacological analyses revealed that the stimulation of putative membrane receptor leads to activation of novel G_<q/11> and phospholipase C, which is followed by [Ca^<2+>]_i increase. We further found that many representative EDCs showed antagonistic actions for DHEAS-induced [Ca^<2+>]_i increase, degranulation and nociception. All these results suggest that the G_<q/11>-coupled neurosteroid receptor may regulate the neuroimmunological activity related to sensory stimulation, and EDCs may exert neuronal actions through a disturbance of this mechanism. Less