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 (P(K,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 P(K,Ca) closure may be beneficial for preventing allergic airway responses.
|Number of pages||4|
|Journal||Methods and Findings in Experimental and Clinical Pharmacology|
|Issue number||SUPPL. C|
|Publication status||Published - 1995|
- plasma leakage
ASJC Scopus subject areas
- Pharmacology (medical)