title: Bronchial circulation and cyclooxygenase products in acute lung injury.
abstract: The role of cyclooxygenase products in the response of the bronchial circulation to acute lung injury was examined in 30 dogs. By use of an open-chest preparation the left lower lobe (LLL) pulmonary circulation was isolated, continuously weighed, and perfused in situ. The anastomotic bronchial blood flow [Qbr(s-p)] was measured as the rate of increase in the volume of the LLL-perfusion circuit. Four groups of dogs were studied. In group A, six dogs received cyclooxygenase inhibition (COI) with either indomethacin (2 mg/kg) or ibuprofen (10 mg/kg). In group B (n = 10) lung injury caused by airway instillation of glucose (15 mg) with glucose oxidase (500 micrograms/kg) (G/GO) or LLL pulmonary arterial infusion of alpha-napthyl thiourea (ANTU, 2 mg/kg). Group C (n = 10) received COI, and 30 min later injury was induced as above with either ANTU or G/GO. Group D (n = 4) received COI immediately after anesthesia; then, 30 min after completion of the surgical preparation, injury was induced with ANTU or G/GO. After COI, Qbr(s-p) decreased to 35 +/- 9% of the basal values (P less than 0.05). After administration of ANTU or G/GO, Qbr(s-p) increased irrespective of whether COI was present. 6-Ketoprostaglandin F1 alpha (6-keto-PGF1 alpha) and thromboxane B2 (TxB2) were measured by radioimmunoassay in the LLL pulmonary artery and systemic venous blood, demonstrating an increase in 6-keto-PGF1 alpha due to surgical preparation and confirming complete COI in those animals receiving COI immediately after anesthesia. These findings demonstrate that 1) the bronchial circulation is capable of a sevenfold increase in flow in response to acute lung injury.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D001095:Arachidonic Acids / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects; D001980:Bronchi / Q000098:blood supply*; D002302:Cardiac Output / Q000187:drug effects; D004285:Dogs; D005260:Female; D007213:Indomethacin / Q000494:pharmacology*; D055370:Lung Injury; D008297:Male; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D011652:Pulmonary Circulation; D012039:Regional Blood Flow
chemical_list: D001095:Arachidonic Acids; D011451:Prostaglandin-Endoperoxide Synthases; D007213:Indomethacin