[The regulating effect of protein kinase C pathway on the airway tone].
OBJECTIVE
To investigate if the role of protein kinase C(PKC) signal pathway in the regulation of tracheal and lung parenchymal strips tone in normal guinea-pigs is different from that in ovalbumin-sensitized ones.


METHODS
By measuring the tones of tracheal and lung parenchymal strips isolated from normal and ovalbumin sensitized guinea-pigs, the effects of PKC-specific activator PMA and inhibitor Ro31-8220 were observed and compared.


RESULTS
(1) PMA caused concentration-dependent relaxations in the tracheal strips of both normal (n = 7) and sensitized animals(n = 7) and the relaxant effects were significantly stronger on the strips from the sensitized animals than on those from the normal ones(P < 0.05). The relaxing effects could be completely inhibited by Ro31-8220. (2) PMA led to concentration-dependent contractions in the lung parenchymal strips and the contractile effects were significantly stronger on the strips from the sensitized animals (n = 5) than on those(n = 6) from the normal ones (P < 0.05). This contractile response could be abolished by Ro31-8220. (3) Ro31-8220 could partly suppress the contractile response of sensitized lung parenchymal strips to in vitro antigen attacks (n = 10, P < 0.01).


CONCLUSIONS
(1) The regulating effects of PKC on airway smooth muscle tone differ in different locations of the guinea-pig airways. (2) The function of PKC signal pathway in airway smooth muscle from sensitized guinea-pig is increased compared with that from normal one. It is suggested that the role of PKC signal pathway may be important in the pathogenesis of asthma.
Liu
X
X
Department of Respiratory Medicine, Tongji Hospital, Tongji Medical University, Wuhan 430030.
Xu
Y
Y
Zhang
Z
Z
D000818:Animals; D001249:Asthma / Q000139:chemically induced / Q000503:physiopathology*; D006168:Guinea Pigs; D007211:Indoles / Q000494:pharmacology*; D008168:Lung / Q000187:drug effects; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects; D010047:Ovalbumin; D011493:Protein Kinase C / Q000502:physiology*; D011897:Random Allocation; D013755:Tetradecanoylphorbol Acetate / Q000037:antagonists & inhibitors*; D014132:Trachea / Q000187:drug effects
D007211:Indoles; D010047:Ovalbumin; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate; C064758:Ro 31-8220