A＿1区参与电刺激颈迷走神经中枢端引起的减压反应

A1 AREA IS INVOLVED IN DEPRESSO RRESPONSE EVOKED BY ELECTRICAL STIMULATION OF CERVICAL VAGALAFFERENTS

在乌拉坦麻醉、双侧切断颈迷走神经的大鼠，电刺激颈迷走神经中枢端可引起各种血压反应。其减压反应可被酚妥拉明（ｉｖ）衰减，而心得安（ｉｖ）则否。室旁核（ＮＰＶ）内注射普鲁卡因也能衰减该反应。Ａ１区和蓝斑均有纤维投射至ＮＰＶ和延髓头端腹外侧交感兴奋区；将普鲁卡因注入Ａ１区可使减压反应减小，但注入蓝斑则不能，提示Ａ１区通过交感缩血管神经和ＮＰＶ参与迷走传入引起的减压反应，蓝斑不参与此反应。

nurethane- anesthetized and bilateral cervical vagotomized rats,electrical stimulation of the cervl- cal vagal afferents usually evoked an initial short- term pressorresponsefollowedbyadepressorrespon-se,and a slow long-lasting pressor respon se after the depressor response. Phentolamine(iv)reduced the depressor response,but propran olol(iv)had no s18njfcantinfluenceonit.Microinjectionofpro-caine into bilateral paraventrlcular nucleus(NPV)could also attenuate the depressor response.Both theA1 area and locus coeruleus(LC)project to the NPV,procaine-injectionmtotheA1areacoulddecre- ase the depressor response,while injection into LC could not.indicatingt hattheA1 areais involved in the depressor response via the sympathetic vasoconstricor nerve as well astheNPV,buttheLCis not involved in this response.