Allergic airway response and potassium channels: histamine release and airway inflammation.
The possible involvement of potassium (K) channels in allergic airway responses was examined in ovalbumin (OA)-sensitized guinea pigs. An ATP-sensitive K channel opener (BRL-38227) inhibited OA inhalation-induced bronchoconstriction and airway plasma leakage. BRL-38227 also had an inhibitory effect on exogenous histamine- and leukotriene-induced responses. In contrast, BRL-38227 did not affect OA-induced histamine release from minced lung tissues. Therefore, the ATP-sensitive K channel opener inhibits allergic bronchoconstriction and plasma leakage as a result of its effect on airway smooth muscle and postcapillary venules. Apamin, a small conductance Ca2+ -activated K channel (PK,Ca) blocker, significantly inhibited both OA-induced tracheal contraction and histamine release from lung tissues, suggesting that this compound reduces allergic airway responses via a mast cell stabilizing effect. We conclude that ATP-sensitive K channel opening and small conductance PK,Ca closure may be beneficial for preventing allergic airway responses.
Ichinose
M
M
First Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
Miura
M
M
Takahashi
T
T
Yamauchi
H
H
Kageyama
N
N
Tomaki
M
M
Endoh
N
N
Sakurai
E
E
Watanabe
T
T
Shirato
K
K
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001578:Benzopyrans / Q000494:pharmacology; D016084:Bronchoconstriction; D002199:Capillary Permeability; D019806:Cromakalim; D006168:Guinea Pigs; D006636:Histamine Release; D006967:Hypersensitivity / Q000517:prevention & control*; D008297:Male; D010047:Ovalbumin / Q000276:immunology; D015221:Potassium Channels / Q000187:drug effects / Q000502:physiology*; D011758:Pyrroles / Q000494:pharmacology
D001578:Benzopyrans; D015221:Potassium Channels; D011758:Pyrroles; D019806:Cromakalim; D000255:Adenosine Triphosphate; D010047:Ovalbumin