CAJ | 학술논문

目的：观察中脑导水管周围灰质腹外侧区（VL-PAG）内促代谢型谷氨酸受体亚型7（mGluR 7）和8（mGluR 8）对大鼠心脏-躯体运动反射（CMR）的调节作用。方法通过心包插管术制作CMR大鼠模型，在VL-PAG内分别注射mGluR 7和mGluR 8的激动剂AMN082和DCPG，观察其对大鼠CMR的调节作用；同时电损毁延髓头端腹内侧区（rostroventral medulla, RVM）亚核中的中缝大核或双侧网状巨细胞核，观察VL-PAG对大鼠CMR的下行调控作用。结果AMN082选择性激活VL-PAG内mGluR 7后，对辣椒素诱发的CMR具有明显的易化作用（P<0.05）；与之相反，DCPG激活VL-PAG内mGluR 8对CAP诱发的CMR具有明显的抑制作用（P<0.05）；这种易化或抑制效应均可被其拮抗剂MSOP完全拮抗；损毁大鼠VL-PAG的主要中继亚核中的中缝大核后，VL-PAG内AMN082微注射所产生的易化效应没有受到明显的影响（P>0.05），VL-PAG内DCPG微注射所产生的抑制效应被部分地减弱（P<0.05）；而双侧网状巨细胞核损毁后，AMN082微注射所产生的易化效应明显被减弱，同时DCPG所产生的抑制效应也有所减弱。结论VL-PAG内mGluR 7和mGluR 8对大鼠CMR具有易化和抑制双向调节效应，而这种双向调节效应很可能是通过RVM的不同亚核、不同神经元的激活而实现的。
목적：관찰중뇌도수관주위회질복외측구（VL-PAG）내촉대사형곡안산수체아형7（mGluR 7）화8（mGluR 8）대대서심장-구체운동반사（CMR）적조절작용。방법통과심포삽관술제작CMR대서모형，재VL-PAG내분별주사mGluR 7화mGluR 8적격동제AMN082화DCPG，관찰기대대서CMR적조절작용；동시전손훼연수두단복내측구（rostroventral medulla, RVM）아핵중적중봉대핵혹쌍측망상거세포핵，관찰VL-PAG대대서CMR적하행조공작용。결과AMN082선택성격활VL-PAG내mGluR 7후，대랄초소유발적CMR구유명현적역화작용（P<0.05）；여지상반，DCPG격활VL-PAG내mGluR 8대CAP유발적CMR구유명현적억제작용（P<0.05）；저충역화혹억제효응균가피기길항제MSOP완전길항；손훼대서VL-PAG적주요중계아핵중적중봉대핵후，VL-PAG내AMN082미주사소산생적역화효응몰유수도명현적영향（P>0.05），VL-PAG내DCPG미주사소산생적억제효응피부분지감약（P<0.05）；이쌍측망상거세포핵손훼후，AMN082미주사소산생적역화효응명현피감약，동시DCPG소산생적억제효응야유소감약。결론VL-PAG내mGluR 7화mGluR 8대대서CMR구유역화화억제쌍향조절효응，이저충쌍향조절효응흔가능시통과RVM적불동아핵、불동신경원적격활이실현적。
Objective To investigate the role of ventrolateral periaqueductal gray (VL-PAG) metabotropic glutamate receptors subtype 7 and 8 (mGluR 7/8) in descending modulation of cardiosomatic motor reflex (CMR) in rats. Methods AMN082 (agonist of mGluR 7) and DCPG (agonist of mGluR 8) were injected into the VL-PAG of a rat model of CMR to observe their effects in modulating CMR. The raphe magnus nucleus (NRM) or the gigantocellular reticular nucleus (Gi) was then damaged, and the changes in VL-PAG descending modulation were observed. Results Selective activation of mGluR 7 of the VL-PAG by AMN082 obviously facilitated capsaicin (CAP)-induced CMR (P<0.05), which was suppressed by DCPG-induced mGluR 8 activation (P<0.05). These facilitatory or inhibitory effects were completely reversed by group III mGluR antagonist MSOP. Damaging the NRM of VL-PAG main relay nucleus did not significantly affect the facilitatory effect produced by AMN082 microinjection (P>0.05), but partially attenuated the inhibitory effect of DCPG microinjection (P<0.05). Both the facilitatory effect of AMN082 and the inhibitory effect of DCPG were reduced obviously after bilateral Gi damage (P<0.05). Conclusion VL-PAG mGluR 7 and mGluR 8 mediate biphasic regulation of CMR in rats probably through activation of different sub-nuclei and different neurons in the rostroventral medulla.