Bronchodilator activity of (3R)-3-[[[(3-fluorophenyl)[(3,4,5-trifluorophenyl)methyl]amino] carbonyl]oxy]-1-[2-oxo-2-(2-thienyl)ethyl]-1-azoniabicyclo[2.2.2]octane bromide (CHF5407), a potent, long-acting, and selective muscarinic M3 receptor antagonist.
The novel quaternary ammonium salt (3R)-3-[[[(3-fluorophenyl)[(3,4,5-trifluorophenyl)methyl]amino]carbonyl]oxy]-1-[2-oxo-2-(2-thienyl)ethyl]-1-azoniabicyclo[2.2.2]octane bromide (CHF5407) showed subnanomolar affinities for human muscarinic M1 (hM1), M2 (hM2), and M3 (hM3) receptors and dissociated very slowly from hM3 receptors (t(&frac12;) = 166 min) with a large part of the receptorial complex (54%) remaining undissociated at 32 h from radioligand washout. In contrast, [(3)H]CHF5407 dissociated quickly from hM2 receptors (t(&frac12;) = 31 min), whereas [(3)H]tiotropium dissociated slowly from both hM3 (t(&frac12;) = 163 min) and hM2 receptor (t(&frac12;) = 297 min). In the guinea pig isolated trachea and human isolated bronchus, CHF5407 produced a potent (pIC(50) = 9.0-9.6) and long-lasting (up to 24 h) inhibition of M3 receptor-mediated contractile responses to carbachol. In the guinea pig electrically driven left atrium, the M2 receptor-mediated inhibitory response to carbachol was recovered more quickly in CHF5407-pretreated than in tiotropium-pretreated preparations. CHF5407, administered intratracheally to anesthetized guinea pigs, potently inhibited acetylcholine (Ach)-induced bronchoconstriction with an ED(50) value of 0.15 nmol/kg. The effect was sustained over a period of 24 h, with a residual 57% inhibition 48 h after antagonist administration at 1 nmol/kg. In conscious guinea pigs, inhaled CHF5407 inhibited Ach-induced bronchoconstriction for at least 24 h as did tiotropium at similar dosages. Cardiovascular parameters in anesthetized guinea pigs were not significantly changed by CHF5407, up to 100 nmol/kg i.v. and up to 1000 nmol/kg i.t. In conclusion, CHF5407 shows a prolonged antibronchospastic activity both in vitro and in vivo, caused by a very slow dissociation from M3 receptors. In contrast, CHF5407 is markedly short-acting at M2 receptors, a behavior not shared by tiotropium.
Villetti
G
G
Department of Preclinical Research and Development, Chiesi Farmaceutici SpA, Parma, Italy.
Pastore
F
F
Bergamaschi
M
M
Bassani
F
F
Bolzoni
P T
PT
Battipaglia
L
L
Amari
G
G
Rizzi
A
A
Delcanale
M
M
Volta
R
R
Cenacchi
V
V
Cacciani
F
F
Zaniboni
M
M
Berti
F
F
Rossoni
G
G
Harrison
S
S
Petrillo
P
P
Santoro
E
E
Scudellaro
R
R
Mannini
F
F
Geppetti
P A
PA
Razzetti
R
R
Patacchini
R
R
Civelli
M
M
D000109:Acetylcholine / Q000494:pharmacology; D000368:Aged; D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001980:Bronchi / Q000187:drug effects; D001986:Bronchial Spasm / Q000139:chemically induced / Q000188:drug therapy / Q000517:prevention & control; D016084:Bronchoconstriction / Q000187:drug effects*; D016085:Bronchoconstrictor Agents / Q000494:pharmacology; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D016466:CHO Cells; D002217:Carbachol / Q000494:pharmacology; D002219:Carbamates / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D006224:Cricetinae; D003412:Cricetulus; D003959:Diamines / Q000008:administration & dosage / Q000494:pharmacology; D006168:Guinea Pigs; D006325:Heart Atria / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D015394:Molecular Structure; D018727:Muscarinic Antagonists / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D009200:Myocardial Contraction / Q000187:drug effects; D011812:Quinuclidines / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D043643:Receptor, Muscarinic M1 / Q000235:genetics / Q000378:metabolism; D043585:Receptor, Muscarinic M2 / Q000819:agonists / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D043587:Receptor, Muscarinic M3 / Q000819:agonists / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D012602:Scopolamine Derivatives / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology; D000069447:Tiotropium Bromide; D014132:Trachea / Q000187:drug effects; D014162:Transfection; D016277:Ventricular Function, Left / Q000187:drug effects
C555557:3-((((3-fluorophenyl)((3,4,5-trifluorophenyl)methyl)amino)carbonyl)oxy)-1-(2-oxo-2-(2-thienyl)ethyl)-1-azoniabicyclo(2.2.2)octane; D016085:Bronchoconstrictor Agents; D001993:Bronchodilator Agents; D002219:Carbamates; D003959:Diamines; D018727:Muscarinic Antagonists; D011812:Quinuclidines; D043643:Receptor, Muscarinic M1; D043585:Receptor, Muscarinic M2; D043587:Receptor, Muscarinic M3; D012602:Scopolamine Derivatives; D002217:Carbachol; D000109:Acetylcholine; C054938:methoctramine; D000069447:Tiotropium Bromide