Prostanoid receptors involved in the relaxation of human bronchial preparations.
1. Iloprost and cicaprost (IP-receptor agonists) induced relaxations in the histamine- (50 microM) contracted human bronchial preparations (pD2 values, 6.63+/-0.12 and 6.86+/-0.08; Emax values, 90+/-04 and 65+/-08% of the papaverine response for iloprost (n=6) and cicaprost (n=3), respectively). 2. Prostaglandin E2 (PGE2) and misoprostol (EP-receptor agonist) relaxed the histamine-contracted human bronchial preparations (pD2 values, 7.13+/-0.07 and 6.33+/-0.28; Emax values, 67+/-04 and 57+/-08% of the papaverine response for PGE2 (n=14) and misoprostol (n=4), respectively). In addition, both relaxations were inhibited by AH6809 (DP/EP1/EP2-receptor antagonist; 3 microM; n=5-6). 3. The PGE2-induced relaxations of human bronchial preparations were not modified by treatment with AH23848B (TP/EP4-receptor antagonist; 30 microM; n=4). 4. The contracted human bronchial preparations were significantly relaxed by prostaglandin D2 (PGD2) or by BW245C a DP-receptor agonist. However, these responses did not exceed 40% of the relaxation induced by papaverine. In addition, the relaxations induced by PGD2 were significantly inhibited by treatment with a DP-receptor antagonist BWA868C (0.1 microM; n=3). 5. These data suggest that the relaxation of human isolated bronchial preparations induced by prostanoids involved IP-, EP2- and to a lesser extent DP-receptors but not EP4-receptor.
Norel
X
X
CNRS ERS 566, Centre Chirurgical Marie Lannelongue, Le Plessis-Robinson, France. xnorel@hotmail.com
Walch
L
L
Labat
C
C
Gascard
J P
JP
Dulmet
E
E
Brink
C
C
D000368:Aged; D001980:Bronchi / Q000502:physiology*; D005260:Female; D006801:Humans; D006827:Hydantoins / Q000494:pharmacology; D016285:Iloprost / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D009126:Muscle Relaxation; D015230:Prostaglandin D2 / Q000494:pharmacology; D011458:Prostaglandins E / Q000494:pharmacology; D011982:Receptors, Prostaglandin / Q000502:physiology*
D006827:Hydantoins; D011458:Prostaglandins E; D011982:Receptors, Prostaglandin; C030669:BW 245C; D016285:Iloprost; D015230:Prostaglandin D2