Differences in the hypoxic contraction of small isolated pulmonary arteries of cat and rabbit

✍ Scribed by Pierre Bonnet; Jorge A. Argibay; Edward White; Didier Garnier

• Publisher: Springer-Verlag
• Year: 1991
• Tongue: English
• Weight: 579 KB
• Volume: 161
• Category: Article
• ISSN: 0174-1578
• DOI: 10.1007/bf00257911

✦ Synopsis

In small (less than 300 microns diameter) pulmonary arterial (PA) rings isolated from the cat, hypoxia induced a transient contraction (250 +/- 120 mg, n = 7), whereas in rings of rabbit PA of the same size, hypoxia had no significant effect (n = 19). Precontraction by 40 mmol KCl.1(-1), noradrenaline (NA) 10(-6) mol.1(-1), or histamine (His 10(-5) mol.1(-1)) did not modify this difference between the two species and did not potentiate the hypoxic contraction of small rings of the cat PA. Large rabbit pulmonary arterial segments (300-2000 microns) exhibited no response to hypoxia before precontraction (n = 15). In the presence of procaine (2%) rabbit PA rings (n = 6, small) exhibited no hypoxic contraction. These results in vitro reflect previous in vivo observations.