Pharmacological modulation of the contractile response to toluene diisocyanate in the rat isolated urinary bladder.
1. Toluene diisocyanate produced concentration-dependent contractions of the rat isolated urinary bladder. 2. The contractions were tetrodotoxin-resistant and were abolished by previous exposure of the strips to capsaicin. 3. Indomethacin (5 microM) and ruthenium red (30 microM) inhibited toluene diisocyanate-induced contractions. Responses expressed as a percentage of the response obtained with substance P, 30 nM, were respectively 141.6 +/- 24.8% and 20.1 +/- 5.1% in control and indomethacin-treated strips (P less than 0.005); 123.0 +/- 30.2% and 14.0 +/- 6.5% in control and ruthenium red-treated strips (0.01 less than P less than 0.05). 4. These results suggest that toluene diisocyanate-induced contractions of the rat isolated bladder are the result of the release of cyclo-oxygenase products which may act by activating the capsaicin receptor.
Institute of Occupational Medicine, University of Padua, Italy.
C E
CE
Mapp
P
P
Chitano
L M
LM
Fabbri
R
R
Patacchini
C A
CA
Maggi
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002211:Capsaicin / Q000494:pharmacology; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D008775:Methylprednisolone / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D012430:Ruthenium Red / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology; D014051:Toluene 2,4-Diisocyanate / Q000494:pharmacology*; D001743:Urinary Bladder / Q000187:drug effects
D012430:Ruthenium Red; D014051:Toluene 2,4-Diisocyanate; D013779:Tetrodotoxin; D001285:Atropine; D002211:Capsaicin; D008775:Methylprednisolone; D007213:Indomethacin