Responses of neurons containing VGLUT3/nNOS-cGMP in the rVLM to cardiac stimulation.
Responses of glutamatergic neurons in the rostral ventrolateral medulla to stimulation of cardiac sympathetic afferents have not been defined. Nitric oxide influences neural function of glutamate. We evaluated the relationship between vesicular glutamate transporter 3, c-Fos and neuronal nitric oxide synthase/soluble guanylyl cyclase in the rostral ventrolateral medulla following cardiac stimulation. In anesthetized cats with barodenervation and vagotomy, epicardial application of bradykinin, but not its vehicle, caused pressor responses. More vesicular glutamate transporter 3-containing neurons colocalized with c-Fos or c-Fos and neuronal nitric oxide synthase in the rostral ventrolateral medulla in bradykinin-treated cats (n = 6; P < 0.05) than in control animals (n = 4). Colocalization of neuronal nitric oxide synthase, soluble guanylyl cyclase and c-Fos or vesicular glutamate transporter 3 was noted following bradykinin stimulation. Findings indicate activation of rostral ventrolateral medulla glutamatergic neurons by cardiac stimulation, which may be influenced by nitric oxide via cGMP.
Guo
Zhi-Ling
ZL
Department of Medicine, University of California, Irvine, Irvine, California 92697-4075, USA. zguo@uci.edu
Longhurst
John C
JC
D000818:Animals; D017763:Autonomic Denervation / Q000379:methods; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D001920:Bradykinin / Q000494:pharmacology; D002415:Cats; D002452:Cell Count / Q000379:methods; D006152:Cyclic GMP / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D006321:Heart / Q000187:drug effects / Q000294:innervation / Q000502:physiology; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008526:Medulla Oblongata / Q000166:cytology*; D009474:Neurons / Q000502:physiology*; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D050496:Vesicular Glutamate Transport Proteins / Q000378:metabolism*
D016760:Proto-Oncogene Proteins c-fos; D050496:Vesicular Glutamate Transport Proteins; D052248:Nitric Oxide Synthase Type I; D006152:Cyclic GMP; D001920:Bradykinin