Occurence of Aminopeptidases (Arylaminopeptidases) in Human Amniotic Fluid and their Participation on Kinin Degradation

Rybák, M.; Zdenka, Blažková, Božena, Gundzová,; Petáková, M.

doi:10.1515/bchm2.1971.352.2.1611

Cited by 9 publications

(4 citation statements)

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“…1 " 4 Amniotic fluid (AF) contains several protease and antiprotease activities. Rybak, et al 5 reported the presence of carboxypeptidase and arylaminoopeptidase in AF, while antitryptic and antichymotryptic activities were found by Bhat, et al 6Ĩ n a recent study, 9 we noted that acid protease activity in AF increases with gestational age. In the present report, we followed acid protease and acid protease inhibitory activities in AF throughout pregnancy.…”

mentioning

confidence: 47%

Amniotic Fluid Protease Activity, Protease Inhibitory Activity, and Fetal Lung Maturity

Menashe¹,

Finci²,

Milwidsky³

et al. 1987

Amer J Perinatol

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Amniotic fluid acid protease and acid protease inhibitory activities were examined in normal pregnancies as a function of gestational age. The acid proteolytic activity of the amniotic fluid is almost constant during gestational weeks 16-29 (26 +/- 13 micrograms globin/ml/2 hrs, mean +/- SD, n = 64). The activity sharply increases after 29 weeks in a time-dependent fashion and reaches a value of 302 +/- 89 (mean +/- SD, n = 13) at 39-40 weeks gestation. Under standard conditions, the ability of amniotic fluid to inhibit bovine pepsin declined during gestation in a linear fashion from 44 +/- 13% (mean +/- SD, n = 36) at 16-18 weeks to 9 +/- 10% (mean +/- SD, n = 41) at 36-40 weeks. A correlation coefficient of r = 0.72 was found between pepsin inhibitory activity and gestational age. No consistent change was noted in the extent of inhibition of the endogenous acid protease throughout pregnancy. In 61 amniotic fluid samples, a correlation coefficient of r = 0.70 was found between acid protease activity and the lecithin/sphingomyelin (L/S) ratio. During the course of this study, five cases of respiratory distress syndrome (RDS) were diagnosed clinically. All five infants had a low protease activity (55 +/- 22 micrograms globin/ml/2 hr, mean +/- SD) as well as a low L/S ratio (0.68 +/- 0.20, mean +/- SD). In contrast, no case of RDS of the newborn was observed among 29 pregnancies with high protease activity and a high L/S ratio. The present observations may suggest a predictive value of amniotic fluid acid protease activity in assessment of fetal lung maturity.

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confidence: 47%

Amniotic Fluid Protease Activity, Protease Inhibitory Activity, and Fetal Lung Maturity

Menashe¹,

Finci²,

Milwidsky³

et al. 1987

Amer J Perinatol

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“…An index of aminopeptidase (arylaniidase) activity and substrate specificity for the N-terminal amino acid of a peptide or protein have been obtained by measuring the hydrolysis of /¿-naphthylamidc derivatives of L-amino acids by serum [Rybak et at., 1971] or microbial [Watson, 1976] enzymes. /¿-Naphthylaniide derivatives (Schwarz-Mann Research Laboratories) of the following L-amino acids v/erc used as substrates to assay for the various aminopeptidase activities: leucine (leu), ¿'-glutamate (7-glu), u-glutamatc (a-glu), alanine (ala), N-tosyl-arginine (N-tos-arg), /¿-aspartate (/¿-asp), glycine (gly), histidine (his), hydroxproline (H pro), isoleucine (isoleu), cystine (cys), methionine (met), ornithine (orn), phenylalanine (phe), proline (pro), threonine (thr), serine tser), tyrosine (tyr), valine (val), lysine (lys), 4-methoxy-leucine (4-methoxy-leu), and tryptophan (try).…”

Section: Methodsmentioning

confidence: 99%

Presence and Development with Age of Aminopeptidase(s) in Tears of Children and other Mammals

Watson

1977

Ophthalmic Res

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Proteolytic enzymes are known to appear in tears only following trauma to the cornea. Aminopeptidases, enzymes involved in the final degradation of proteins to free amino acids, were measured and partially characterized for substrate specificity in normal human and animal tears. In all species tested, aminopeptidase activity was greatest for methionine β-naphthylamide of the various synthetic analogs of N-terminal L-amino acids. The substrate specificities for aminopeptidase(s) in tears for 11 different mammals were very similar. In children aminopeptidase activity decreased with increasing age and was unaffected by nutritional status.

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“…Rybak et al [5] de scribed carboxypeptidase and arylaminopeptidases in the amniotic fluid which might participate in kinin degradation. Others re ported that the amniotic fluid contains aiantitrypsin [13,14], and Bhat et al [15] and Bhat and Pattabiraman [16] found a glyco protein which inhibits trypsin and Chymo trypsin in an uncompetitive manner.…”

Section: Wmentioning

confidence: 99%

“…Since the strength of the membranes physiological and pathological processes is available [4]. However, only little is known on the proteolytic activity in fetal mem branes and in amniotic fluid [5,6], and the potential role of proteases in the etiology of PROM is as yet unknown [5].…”

Section: Introductionmentioning

confidence: 99%

Proteolytic Enzymes in Human Fetal Membranes and Amniotic Fluid

Milwidsky¹,

Hurwitz²,

Eckstein³

et al. 1985

Enzyme

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The amniotic and chorionic membranes obtained at term and term amniotic fluid contain a soluble protease activity which cleaves [^14C]-labeled globin at acid pH. In contrast, a salt extract of the pellet fraction obtained from the fetal membranes displays only negligible protease activities at the pH range of 4-8. Specific activities of the proteases in the soluble and salt-extractable fractions of fetal membranes which were intact before onset of labor were not significantly different from the respective activities in cases of premature rupture of fetal membranes (PROM). However, the protease activity of the amniotic fluid was found to increase with advancing gestational age and to reach maximal activity at term. A heat-sensitive and nondializable protease inhibitory activity was found in term amniotic fluid. This inhibitory activity acted on the cytosolic protease of amniotic membranes from control and PROM cases, but not on the soluble protease of chorionic membranes, and had a similar potency in fluids from PROM cases or fluids collected at term. These results do not support a role for fetal membrane proteases, amniotic fluid proteases, or amniotic fluid protease inhibitory activities in the etiology of PROM. However, the observed changes in amniotic fluid protease activity with fetal age suggest a physiological role for the enzyme in normal fetal development.

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Occurence of Aminopeptidases (Arylaminopeptidases) in Human Amniotic Fluid and their Participation on Kinin Degradation

Cited by 9 publications

References 0 publications

Amniotic Fluid Protease Activity, Protease Inhibitory Activity, and Fetal Lung Maturity

Amniotic Fluid Protease Activity, Protease Inhibitory Activity, and Fetal Lung Maturity

Presence and Development with Age of Aminopeptidase(s) in Tears of Children and other Mammals

Proteolytic Enzymes in Human Fetal Membranes and Amniotic Fluid

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