In vitro stability of human atrial natriuretic peptide(h-ANP)

1. The effect of a α-human atrial natriuretic peptide (1–28) (ANP) on human vasculature was investigated in vivo and in vitro. Possible involvement of vascular dopamine receptors and the renin-angiotensin system in the response to ANP was also studied in vivo. 2. Forearm blood blow was measured by venous occlusion plethysmography. Isolated human blood vessels were studied using conventional organ bath techniques. 3. ANP (0.1–1 μg/min, intra-arterially) produced a dose-dependent increase in forearm blood flow, corresponding to a 163% increase in net forearm blood flow in the study arm. This action of ANP was not antagonized by (R)-sulpiride (100 μg/min, intra-arterially), a selective vascular dopamine receptor antagonist, or 50 mg of oral captopril, an inhibitor of angiotensin-converting enzyme. 4. ANP (1 nmol/l–1 μmol/l) produced concentration-dependent relaxation of isolated human arteries, including brachial artery, but was without effect on isolated human saphenous vein. 5. ANP produces vasodilatation in vivo and relaxes isolated human arterial smooth muscle. This action of ANP may contribute to its reported hypotensive effects in vivo.

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Influence of storage conditions on in vitro stability of atrial natriuretic peptide and of anesthesia on plasma atrial natriuretic peptide concentration in cats

American Journal of Veterinary Research ◽

10.2460/ajvr.77.8.854 ◽

2016 ◽

Vol 77 (8) ◽

pp. 854-859 ◽

Cited By ~ 1

Author(s):

Yasuhiro Heishima ◽

Yasutomo Hori ◽

Seishiro Chikazawa ◽

Kazutaka Kanai ◽

Fumio Hoshi ◽

...

Keyword(s):

Atrial Natriuretic Peptide ◽

Natriuretic Peptide ◽

Storage Conditions ◽

Plasma Atrial Natriuretic Peptide ◽

Peptide Concentration ◽

In Vitro Stability ◽

Atrial Natriuretic

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The hydrolysis of α-human atrial natriuretic peptide by pig kidney microvillar membranes is initiated by endopeptidase-24.11

Biochemical Journal ◽

10.1042/bj2430183 ◽

1987 ◽

Vol 243 (1) ◽

pp. 183-187 ◽

Cited By ~ 226

Author(s):

S L Stephenson ◽

A J Kenny

Keyword(s):

Atrial Natriuretic Peptide ◽

Natriuretic Peptide ◽

Angiotensin I ◽

Human Atrial Natriuretic Peptide ◽

Pig Kidney ◽

Angiotensin I Converting Enzyme ◽

Endopeptidase 24.11 ◽

Hydrolysis Of ◽

Atrial Natriuretic

alpha-Human atrial natriuretic peptide, a 28-amino-acid-residue peptide, was rapidly hydrolysed by pig kidney microvillar membranes in vitro, with a t1/2 of 8 min, comparable with the rate observed with angiotensins II and III. The products of hydrolysis were analysed by h.p.l.c., the pattern obtained with membranes being similar to that with purified endopeptidase-24.11 (EC 3.4.24.11). No hydrolysis by peptidyl dipeptidase A (angiotensin I converting enzyme, EC 3.4.15.1) was observed. The contribution of the various microvillar membrane peptidases was assessed by including specific inhibitors. Phosphoramidon, an inhibitor of endopeptidase-24.11, caused 80-100% suppression of the products. Captopril and amastatin (inhibitors of peptidyl dipeptidase A and aminopeptidases respectively) had no significant effect. Hydrolysis at an undefined site within the disulphide-linked ring occurred rapidly, followed by hydrolysis at other sites, including the Ser25--Phe26 bond.

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Hydrolysis of α-human atrial natriuretic peptide in vitro by human kidney membranes and purified endopeptidase-24.11. Evidence for a novel cleavage site

Biochemical Journal ◽

10.1042/bj2540531 ◽

1988 ◽

Vol 254 (2) ◽

pp. 531-537 ◽

Cited By ~ 49

Author(s):

Y Vanneste ◽

A Michel ◽

R Dimaline ◽

T Najdovski ◽

M Deschodt-Lanckman

Keyword(s):

Atrial Natriuretic Peptide ◽

Natriuretic Peptide ◽

Bond Cleavage ◽

Human Kidney ◽

Human Atrial Natriuretic Peptide ◽

Endopeptidase 24.11 ◽

Therapeutic Uses ◽

Atrial Natriuretic

alpha-Human atrial natriuretic peptide (hANP) is secreted by the heart and acts on the kidney to promote a strong diuresis and natriuresis. In vivo it has been shown to be catabolized partly by the kidney. Crude microvillar membranes of human kidney degrade 125I-ANP at several internal bonds generating metabolites among which the C-terminal fragments were identified. Formation of the C-terminal tripeptide was blocked by phosphoramidon, indicating the involvement of endopeptidase-24.11 in this cleavage. Subsequent cleavages by aminopeptidase(s) yielded the C-terminal dipeptide and free tyrosine. Using purified endopeptidase 24.11, we identified seven sites of hydrolysis in unlabelled alpha-hANP: the bonds Arg-4-Ser-5, Cys-7-Phe-8, Arg-11-Met-12, Arg-14-Ile-15, Gly-16-Ala-17, Gly-20-Leu-21 and Ser-25-Phe-26. However, the bonds Gly-16-Ala-17 and Arg-4-Ser-5 did not fulfil the known specificity requirements of the enzyme. Cleavage at the Gly-16-Ala-17 bond was previously observed by Stephenson & Kenny [(1987) Biochem. J. 243, 183-187], but this is the first report of an Arg-Ser bond cleavage by this enzyme. Initial attack of alpha-hANP by endopeptidase-24.11 took place at a bond within the disulphide-linked loop and produced a peptide having the same amino acid composition as intact ANP. The bond cleaved in this metabolite was determined as the Cys-7-Phe-8 bond. Determination of all the bonds cleaved in alpha-hANP by endopeptidase-24.11 should prove useful for the design of more stable analogues, which could have therapeutic uses in hypertension.

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