Nedocromil sodium modulates nonadrenergic, noncholinergic bronchoconstrictor nerves in guinea pig airways in vitro.
Nonadrenergic, noncholinergic (NANC) neural bronchoconstrictor responses in guinea pig airways are due to the release of tachykinins from sensory nerves. We have performed an in vitro study using electrical field stimulation (EFS; 40 V, 0.5 ms, 8 Hz for 20 s) in guinea pig bronchi to investigate the effect of nedocromil sodium (NS) on NANC bronchoconstrictor responses. NS inhibited NANC bronchoconstriction in bronchi in a concentration-dependent manner, with a maximum inhibition of 40 +/- 4% (p less than 0.001, n = 6) at 100 microM. Cromolyn sodium, however, produced only 9 +/- 8% inhibition at the same molar concentration (p less than 0.05). NS did not affect the contractile response to substance P, nor did it modulate the cholinergic bronchoconstrictor response to EFS in tracheal smooth muscle. These results indicate that NS may modulate the release of tachykinins from airway sensory nerves.
Department of Thoracic Medicine, National Heart and Lung Institute, London, United Kingdom.
G M
GM
Verleden
M G
MG
Belvisi
C D
CD
Stretton
P J
PJ
Barnes
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D001980:Bronchi / Q000294:innervation*; D016084:Bronchoconstriction / Q000502:physiology*; D002217:Carbachol / Q000494:pharmacology; D004205:Cromolyn Sodium / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D017835:Nedocromil; D015363:Quinolones / Q000494:pharmacology*; D013373:Substance P / Q000494:pharmacology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D015363:Quinolones; D017835:Nedocromil; D013373:Substance P; D002217:Carbachol; D004205:Cromolyn Sodium