Respiratory depression produced by intravenously administered NBQX.
To determine whether blockade of non-N-methyl-D-aspartate (non-NMDA) excitatory amino acid receptors affects breathing, we administered the non-NMDA receptor antagonist, 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (NBQX), to anesthetized cats while monitoring phrenic nerve discharge, blood pressure and heart rate. NBQX, 3 and 10 mg/kg, i.v., reduced phrenic amplitude 59 +/- 20% (n = 3) and 88 +/- 6% (n = 5), respectively, and decreased respiratory rate. Phrenic activity was completely silenced in 3 animals. These effects were accompanied by decreased blood pressure and heart rate. Our data indicate that NBQX, a competitive antagonist of non-NMDA receptors, is a powerful depressant of cardiorespiratory activity.
McManigle
J E
JE
Department of Pharmacology, Georgetown University School of Medicine, Washington, DC 20007, USA.
Gillis
R A
RA
Dretchen
K L
KL
Taveira Da Silva
A M
AM
Hernandez
Y M
YM
D000818:Animals; D001049:Apnea / Q000139:chemically induced / Q000503:physiopathology; D016275:Atrial Function / Q000187:drug effects / Q000502:physiology; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D002415:Cats; D004305:Dose-Response Relationship, Drug; D018691:Excitatory Amino Acid Antagonists / Q000008:administration & dosage / Q000009:adverse effects*; D006339:Heart Rate / Q000187:drug effects; D007275:Injections, Intravenous; D010791:Phrenic Nerve / Q000187:drug effects / Q000502:physiology; D011810:Quinoxalines / Q000008:administration & dosage / Q000009:adverse effects*; D012131:Respiratory Insufficiency / Q000139:chemically induced*; D012143:Respiratory Physiological Phenomena / Q000187:drug effects; D012137:Respiratory System / Q000187:drug effects / Q000294:innervation
D018691:Excitatory Amino Acid Antagonists; D011810:Quinoxalines; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline