Control of the mucosal microcirculation in the upper respiratory tract.
This study was designed to investigate the regulatory mechanisms of the mucosal microvascular network in the upper respiratory tract. Tracheal mucosal circulation was observed using a specially constructed chamber that allowed direct microscopic visualization of mucosal arterioles. Solutions of increasing hypertonicity (500 and 900 mOsm) applied to the tracheal epithelium resulted in increasing dilation of the underlying mucosal arterioles (p < 0.001). N(omega)-nitro-L-arginine methyl ester (L-NAME, 1 mmol/L), a specific inhibitor of nitric oxide synthesis, added to a hypertonic solution inhibited dilation of mucosal arterioles (p < 0.001). Addition of the substrate for nitric oxide synthesis, L-arginine (0.6 mmol/L) to the hypertonic solution containing L-NAME resulted in dilation of mucosal arterioles once again. These data demonstrate that nitric oxide is a crucial mediator in the response of mucosal arterioles to the hypertonic stimulus presented to the epithelial surface of the trachea. Further elucidation of the control of the mucosal microcirculation in the upper respiratory tract could be implemented in new treatment for pathologic processes of the upper respiratory tract such as mucosal congestion and edema.
Smith
T L
TL
Division of Otolaryngology-Head and Neck Surgery, University of North Carolina School of Medicine, Chapel Hill 27599-7070.
Prazma
J
J
Coleman
C C
CC
Drake
A F
AF
Boucher
R C
RC
D000704:Analysis of Variance; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D001160:Arterioles / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004848:Epithelium / Q000098:blood supply / Q000187:drug effects; D006652:Histological Techniques; D006982:Hypertonic Solutions; D007552:Isotonic Solutions; D009092:Mucous Membrane / Q000098:blood supply / Q000187:drug effects; D019331:NG-Nitroarginine Methyl Ester; D009569:Nitric Oxide / Q000037:antagonists & inhibitors; D051381:Rats; D017207:Rats, Sprague-Dawley; D012137:Respiratory System / Q000098:blood supply* / Q000187:drug effects; D014132:Trachea / Q000098:blood supply / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects
D006982:Hypertonic Solutions; D007552:Isotonic Solutions; C051865:Krebs-Ringer solution; D009569:Nitric Oxide; D001120:Arginine; D019331:NG-Nitroarginine Methyl Ester