Atenolol, exaprolol and mast cell membranes.

Lipophilic exaprolol and hydrophilic atenolol differ in their interaction with mast cell membranes. Exaprolol, as compared with atenolol, significantly decreased 32P incorporation into, but increased arachidonic acid liberation from, membrane phospholipids. Moreover, exaprolol significantly decreased phosphate incorporation in compound 48/80 and ConA-PS treated cells and decreased thromboxane formation in stimulated cells. On the other hand, atenolol decreased significantly only arachidonate liberation from stimulated mast cells. These results corroborate to some extent the effect of exaprolol and atenolol on histamine liberation which correlates with their membrane perturbing properties.