The influence of xanthines on the contractile responses of PGF2 alpha and PGD2 in human parenchymal strips.
Prostaglandins (PGs) F2 alpha and D2 are bronchoconstrictor agents which are released under allergic conditions such as asthma. The efficacy and potency of PGF2 alpha and PGD2 differ in some tissues. We compared the effects of these two PGs in sensitized human parenchymal strips. In six experiments, PGF2 alpha 0.1 and 0.3 microM produced greater contractions than PGD2 at the same concentrations. There were no significant differences between the contractions from the two PGs at concentrations of 0.01, 0.03, 1.0-10 microM and the two PGs appeared to be equipotent. We studied the effects of the anti-asthmatic drug theophylline, and its analogue enprofylline, on the contraction caused by these PGs. Theophylline 100 microM caused no change to the cumulative concentration response curves. However, enprofylline 100 microM reduced the PGF2 alpha-induced contractions.
Dept. of Pharmacology, University of Sydney, Australia.
F E
FE
Napier
D M
DM
Temple
D001993:Bronchodilator Agents / Q000494:pharmacology; D015237:Dinoprost / Q000494:pharmacology*; D006632:Histamine; D006801:Humans; D008168:Lung / Q000187:drug effects*; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D015230:Prostaglandin D2 / Q000494:pharmacology*; D013806:Theophylline / Q000494:pharmacology*; D014970:Xanthines / Q000494:pharmacology*
D001993:Bronchodilator Agents; D014970:Xanthines; D006632:Histamine; D015237:Dinoprost; D013806:Theophylline; C034347:enprofylline; D015230:Prostaglandin D2