Proline in vasoactive peptides: consequences for peptide hydrolysis in the lung. Am J Physiol 1999 Feb;276(2):L341-50
Date
02/10/1999Pubmed ID
9950897DOI
10.1152/ajplung.1999.276.2.L341Scopus ID
2-s2.0-0033062004 (requires institutional sign-in at Scopus site) 4 CitationsAbstract
To examine the hypothesis that trans isomers of bradykinin and [Gly6]bradykinin are preferentially hydrolyzed by lung peptidases, we studied the fractional inactivation of these peptides in the perfused rat lung using a bioassay after a single-pass bolus injection and high-performance liquid chromatography after lung recirculation. In the bioassay studies, when the peptides passed through the lung, 25.6-fold more bradykinin or 7-fold more [Gly6]bradykinin was required to elicit a contraction equivalent to that produced when the peptides did not pass through the lung. In the recirculation studies, hydrolysis progress curves with rapid and slow phases were observed, with a higher fraction of bradykinin than [Gly6]bradykinin hydrolyzed in the rapid phase. Cyclophilin increased the hydrolysis rate during the slow phase for both peptides. Kinetic analysis indicated that the slowly hydrolyzed peptide fraction, presumably the cis fraction, was 0.13 for bradykinin and 0.43 for [Gly6]bradykinin with cis-trans isomerization rate constants of 0.074 and 0.049 s-1, respectively, consistent with published nuclear magnetic resonance studies.
Author List
Merker MP, Audi SH, Brantmeier BM, Nithipatikom K, Goldman RS, Roerig DL, Dawson CAAuthor
Said Audi PhD Professor in the Biomedical Engineering department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AnimalsBradykinin
Hydrolysis
Kinetics
Lung
Male
Models, Biological
Proline
Rabbits
Rats
Rats, Wistar
Stereoisomerism
