HISTAMINE AND THE NASAL VASCULATURE - THE INFLUENCE OF H-1 AND H-2-HISTAMINE RECEPTOR ANTAGONISM

The aim was to determine the effect of H-1- and H-2-receptor blockade on histamine-induced changes in nasal airways resistance and lavage pr otein concentrations. Normal subjects were pretreated with oral cetiri zine or ranitidine in a double-blind and randomized manner. Measuremen ts of the concentration of total protein and albumin in nasal lavage f luid together with nasal airway resistance were made before and after challenge. Any effect of treatment was assessed by comparing the areas under the time-response curves. In all nine subjects available for an alysis histamine caused an immediate increase in all measurements. Ran itidine reduced the maximum increase in nasal airway resistance, but t his effect was significant only in combination with cetirizine. The in crease in lavage total protein and albumin concentrations was almost c ompletely abolished by cetirizine, whereas ranitidine had less effect. We conclude that the histamine H-1-receptor has the greatest effect o n changes in nasal vascular permeability induced by topical histamine, whereas the H-2-receptor has the greatest effect on nasal obstruction .