Degradation of bradykinin by isolated perfused rat lung
Several studies have suggested that the essentially complete degradation of circulating bradykinin (BK) in lung is mediated in part by peptidase(s) other than the well-characterized angiotensin converting enzyme (ACE). The authors report here that the isolated perfused rat lung can inactivate BK by sequential N-terminal cleavage. (/sup 3/H-2, 3-Pro) BK was perfused through the lung and the products in the perfusate identified by HPLC. In the absence of inhibitors, BK was 89-100% degraded with /sup 3/H-Pro/sup 2/-Pro/sup 3/ and /sup 3/H-Pro as the major products. The dipeptidylaminopeptidase IV (DAP IV) inhibitor, diprotein A (Ile-Pro-Ile), greatly reduced the Pro-Pro and Pro peaks and produced a prominent BK/sub 2-7/ peak (or BK/sub 2-9/ peak if the ACE inhibitor, captopril, was also present). 2-Mercapto-ethanol, a rather specific inhibitor of aminopeptidase P (AP-P), prevented the release of Arg/sup 1/, producing major BK and/or BK/sub 1-7/ peaks. The neutral metalloendopeptidase inhibitor, phosphoramidon, had no effect on the pattern of degradation of BK by the perfused rat lung by the release of Arg/sup 1/ by AP-P followed by release of Pro/sup 2/-Pro/sup 3/ by DAP IV.
- Research Organization:
- Loyola Univ. Medical Center, Maywood, IL
- OSTI ID:
- 5388272
- Report Number(s):
- CONF-8604222-; TRN: 86-030485
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:3; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
- Country of Publication:
- United States
- Language:
- English
Similar Records
Metabolism of enkephalin in stomach wall of rats
Novel sodium channel inhibitor from Conus geographus: purification, structure, and pharmacological properties
Related Subjects
BRADYKININ
METABOLISM
PEPTIDE HYDROLASES
ENZYME ACTIVITY
CLEAVAGE
ENZYME INHIBITORS
LIQUID COLUMN CHROMATOGRAPHY
LUNGS
PERFUSED ORGANS
RATS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANIMALS
BODY
CHROMATOGRAPHY
CRYSTAL STRUCTURE
ENZYMES
HYDROLASES
ISOTOPE APPLICATIONS
KININS
LABELLED COMPOUNDS
MAMMALS
MICROSTRUCTURE
ORGANIC COMPOUNDS
ORGANS
PEPTIDES
POLYPEPTIDES
PROTEINS
RESPIRATORY SYSTEM
RODENTS
SEPARATION PROCESSES
VERTEBRATES
550501* - Metabolism- Tracer Techniques