Prostaglandin E1 enhances the histamine induced stimulation of the mucociliary activity in the rabbit maxillary sinus

Inflammatory mediators are released in the airways during both inflammatory and allergic reactions, and many of these mediators affect mucociliary activity. To discover whether mucociliary activity is changed by a combination of mediators, the interaction between prostaglandins and histamine or methacholine was studied in vivo in the rabbit maxillary sinus. We used a photoelectric technique and recorded frequency changes induced by tested substances. Prostaglandins E1 and F2 alpha (PGE1 and PGF2 alpha) were given as ia. infusions followed by bolus injections of histamine or methacholine. Infusion with PGE1 (0.1 microgram.kg-1) enhanced the stimulating effect of a subsequent injection of histamine (10 micrograms.kg-1), maximum stimulation being 33 +/- 6% compared to 14 +/- 4% after histamine alone (p = 0.02). When the histamine injection was given 20 min after PGE1 no enhancement was observed. PGE1 did not enhance the stimulating effect of methacholine. In contrast to PGE1, PGF2 alpha failed to enhance the effect of histamine. It is proposed that a role of PGE1 is to modify the mucociliary response to other mediators released during inflammatory and allergic reactions.