| Popis: |
The effects of recycling paper dust extract on isolated nonsensitized guinea pig tracheal smooth muscle were studied in vitro. Dust extract was prepared as a 1:10 w/v aqueous solution. Dose related contractions of guinea pig tracheal rings were elicited with paper dust extract. Pharmacologic studies were performed with atropine (10(-6) M), indomethacine (10(-6) M), pyrilamine (10(-6) M), Ly 171883 (10(-5) M), NDGA (10(-5) M) and TMB8 (10(-5) M). The effects of extract were almost totally inhibited by the anticholinergic agent atropine, suggesting that a principal pathway mediating this response may involve the parasympathetic nervous system. The intracellular calcium blocking agent TMB8 also induced a reduction of the contractile response to paper dust extract, which is consistent with intracellular calcium's well established role in smooth muscle constriction. We suggest that paper dust extract causes dose related airway smooth muscle constriction, possibly associated with the release of cholinergic as well as other mediators. The constrictor effect does not require tissue presensitization. |
