Differential Adrenoreceptor Mediated Tachyphylaxis and Upregulation
Status:
Completed
Trial end date:
2009-05-01
Target enrollment:
Participant gender:
Summary
The investigators wish to evaluate the onset of tolerance to nasal decongestants like
oxymetazoline (available over the counter) and the mechanism of tolerance particularly with
differential effects on alpha 1 and alpha 2 adrenoreceptors on the nose. The investigators
will 'tease' out by using an alpha 1 blocker called Prazosin. The investigators hypothesize
that alpha 1 receptors mediate arterial constriction and this will be captured by measuring
nasal blood flow. The investigators also hypothesize that alpha 2 receptors mediate venous
sinusoid constriction and this the investigators will capture by airflow parameters like Peak
Nasal Inspiratory Flow, Rhinomanometry, Oscillometric indices etc.