1-O-octadecyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (AGEPC) induced in vitro a slowly-developing contraction of rabbit lung parenchymal strips by a mechanism distinct from those of histamine, acetylcholine and C5a. AGEPC appeared more potent on a molar basis than histamine, acetylcholine and C5a. However, rabbit lung tissue appeared more sensitive in terms of magnitude of maximal contraction to histamine-dependent agents (histamine and C5a). Prior in vitro exposure of lung tissue to AGEPC resulted in desensitization to AGEPC, but not to histamine, acetylcholine and C5a. The in vivo infusion of AGEPC in the rabbit, which resulted in cardio-vascular and respiratory changes characteristic of an anaphylactoid reaction, induced complete desensitization of lung parenchymal strips, obtained 30 min after infusion, to AGEPC but not to histamine, acetylcholine and C5a. These data suggest an in vivo interaction between the injected AGEPC and the lung smooth muscle receptors.
ASJC Scopus subject areas
- Pharmacology (medical)