Effect of baclofen on different models of bronchial hyperreactivity in the guinea-pig.

In this paper we report an inhibitory effect of (-)-baclofen on many models of bronchial hyperreactivity both in vivo and in vitro. (-)-Baclofen protects guinea-pigs from the anaphylactic bronchospasm induced in sensitized animals by an ovalbumin aerosol and from that induced by aerosols of histamine and PGF2 alpha. Moreover (-)-baclofen reduces the TXA2 and TXB2 output induced by ovalbumin from isolated sensitized guinea-pig lungs. On the other hand (-)-baclofen does not show antihistaminic, anticholinergic or antiprostaglandinic action on isolated tracheal preparations. It is concluded that baclofen can provide protection from bronchial hyperreactivity possibly through a modulation of autonomic nervous system activity.