Searching the ideal inhaled vasodilator: From nitric oxide to prostacyclin

Today, the technique to directly administer vasodilators via the
airway to treat pulmonary hypertension and to improve pulmonary gas
exchange is widely accepted among clinicians. The flood of
scientific work focussing on this new therapeutic concept had been
initiated by a fundamental new observation by Pepke-Zaba {[}1] and
Frostell in 1991 {[}2]: Both scientists reported, that inhalation
of exogenous nitric oxide (NO) gas selectively dilates pulmonary
vessels without a concomittant systemic vasodilation. No more than
another decade ago NO was identified as an important endogenous
vasodilator {[}3] while having merely been regarded an
environmental pollutant before that time. Although inhaled NO
proved to be efficacious, alternatives were sought-after due to
NO's potential side-effects. In search for the ideal inhaled
vasodilator another group of endogenous mediators - the prostanoids
- came into the focus of interest. The evidence for safety and
efficacy of inhaled prostanoids is - among a lot of other valuable
work - based on a series of experimental and clinical
investigations that have been performed or designed at the
Institute for Surgical Research under the guidance and mentorship
of Prof. Dr. med. Dr. h.c. mult. K. Messmer {[}4-19]. In the
following, the current and newly emerging clinical applications of
inhaled prostanoids and the experimental data which they are based
on, will be reviewed. Copyright (C) 2002 S. Karger AG, Basel.