Effect of endothelin-1 on blood pressure and bronchopulmonary system of the guinea pig.
The bronchopulmonary and pressor effects of endothelin-1 (ET-1), a newly described vasoconstrictor peptide produced by endothelial cells, were investigated in the guinea pig. Intravenous injection of ET-1 (1 nmol/kg) induced an increase in pulmonary inflation pressure (PIP) as well as an important and sustained increase in arterial blood pressure (BP). Pretreatment of these animals with propranolol (1 mg/kg i.v.), provoked a significant enhancement of the ET-1-induced increase in PIP, accompanied by a dramatic and significant decrease of BP. When administered by aerosol for 1 min, ET-1 (1, 5, or 10 micrograms/ml) induced a dose-dependent increase in PIP that was maximal by 4-5 min, but no significant change of BP. Pretreatment of guinea pigs with propranolol (1 mg/kg), mepyramine (1 mg/kg i.v.), nifedipine (50 mg/kg i.p.), or verapamil (0.3 mg/kg i.v.) did not inhibit the bronchopulmonary response evoked by aerosol administration of 10 micrograms/ml of ET-1. In contrast, pretreatment of the animals with indomethacin (10 mg/kg i.v.) or BN 52021 (10 mg/kg i.v.) significantly reduced the bronchopulmonary response of ET-1 given by aerosol. Injection of ET-1 (0.1, 0.3, and 1 micrograms) into isolated guinea pig lungs caused significant increases in PIP that were accompanied by the release of TxB2 but not histamine. These results demonstrate that ET-1 induces bronchopulmonary alterations in the guinea pig that appear to be dissociated from the systemic vascular effects of the peptide.
Braquet
P
P
Institut Henri Beaufour, Le Plessis Robinson, France.
Touvay
C
C
Lagente
V
V
Vilain
B
B
Pons
F
F
Hosford
D
D
Chabrier
P E
PE
Mencia-Huerta
J M
JM
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D001980:Bronchi / Q000187:drug effects; D016232:Endothelins; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007275:Injections, Intravenous; D008168:Lung / Q000187:drug effects; D008297:Male; D010455:Peptides / Q000494:pharmacology*; D012119:Respiration / Q000187:drug effects; D012137:Respiratory System / Q000187:drug effects*; D013929:Thromboxane B2 / Q000494:pharmacology
D016232:Endothelins; D010455:Peptides; D013929:Thromboxane B2