Cardiovascular peptide research is dominated by two opposing hormone systems — the vasoconstrictor renin–angiotensin and endothelin axes on one side, the vasodilator natriuretic peptides on the other — plus a growing set of adipose- and endothelium-derived regulators. Our cardiovascular topic page collects the peptide standards, antisera, tracers and immunoassay kits used across that literature. This guide maps which families sit inside the topic, what each is ordered for, and which reagent format answers which experimental question.
What sits under the cardiovascular topic
A family is filed here when its parent peptide is produced by, or acts on, the heart, vasculature, kidney or the neuroendocrine circuits controlling blood pressure and volume. That covers circulating hormones, locally acting paracrine peptides, and the biomarkers used to phenotype animal models of hypertension, heart failure and vascular injury. Several families are shared with other topics — angiopoietin with cancer angiogenesis work, apelin and adrenomedullin with metabolic studies. Every item is supplied for in-vitro and approved animal research only; none is a diagnostic or therapeutic product.
Natriuretic peptides: the biomarker core
No family in this topic is ordered more often, because ANP and BNP are the standard readouts of cardiac load in animal models:
- ANP — atrial natriuretic peptide, the 28-residue hormone released on atrial stretch; supplied as the mature peptide, as proANP fragments and as species variants.
- BNP — brain (B-type) natriuretic peptide and the NT-proBNP fragment that dominates biomarker work, because the cleaved N-terminal fragment is more stable in plasma than the active hormone.
- CNP — the endothelium-derived C-type peptide acting through NPR-B, studied in vascular tone and bone growth rather than volume regulation.
- DNP — the Dendroaspis natriuretic peptide, a snake-venom-derived tool used to probe receptor pharmacology.
All four are commonly ordered together with the matching EIA kits, since the quantitative question is usually plasma concentration in a model.
Vasoconstrictor and pressure-regulating families
- Angiotensin — the largest family in this topic: Ang I, Ang II, Ang-(1–7), Ang IV and receptor-selective analogs. Ang-(1–7)/Mas signalling is the fastest-growing branch of the renin–angiotensin system literature.
- Endothelin — ET-1, ET-2, ET-3 and big-endothelin precursors; ET-1 remains the most potent endogenous vasoconstrictor characterised and a standard positive control in vascular reactivity assays.
- Urotensin II — a cyclic peptide with vasoconstrictor activity that varies strikingly by vessel bed and species, which is why species-matched standards matter here more than elsewhere.
- Vasopressin and copeptin — the antidiuretic hormone and its stable C-terminal precursor fragment; copeptin is measured in place of vasopressin precisely because the parent hormone is unstable in plasma.
- Bradykinin — the kallikrein–kinin vasodilator arm, ordered as the nonapeptide, as des-Arg fragments and as B1/B2 receptor tools.
Endothelium- and adipose-derived regulators
- Apelin and ELABELA (Toddler) — the two endogenous ligands of the APJ receptor; apelin isoforms (apelin-13, pyroglutamated apelin-13, apelin-17, apelin-36) differ substantially in potency and stability, so the isoform must be specified.
- Adrenomedullin and intermedin (AM2) — CGRP-superfamily vasodilators studied in sepsis, heart failure and vascular permeability models.
- CGRP — calcitonin gene-related peptide; the α and β isoforms plus the antagonist fragment CGRP(8–37) support both vascular and neurogenic work.
- Urocortin — CRF-family peptides with pronounced cardioprotective effects reported in ischaemia–reperfusion models.
- Catestatin, chromogranin A and salusin — chromogranin-derived and related peptides with autonomic and vascular activity.
- Adropin and EC-SOD — endothelial function and oxidative-stress reagents, increasingly paired with metabolic phenotyping.
- Ac2-26 — the annexin A1 N-terminal peptide, a formyl peptide receptor agonist widely used as a pro-resolving control in vascular inflammation studies.
- PF4 and thrombospondin — platelet-derived families bridging thrombosis and angiogenesis.
- Relaxin — vasodilatory and anti-fibrotic peptide hormone, studied in heart-failure and pregnancy-adaptation models.
Which formats the cardiovascular topic contains
Synthetic peptide standards supply agonists, antagonist fragments and immunoassay calibrators. Labeled peptides are unusually important here because receptor autoradiography and competition binding on vascular tissue historically depend on I-125 tracers of angiotensin II, endothelin-1 and ANP. Polyclonal antisera support immunohistochemistry on heart, kidney and vessel sections. EIA and RIA kits carry most of the quantitative load — plasma ANP, BNP, endothelin-1 and copeptin measurements in rodent models are routine. Pull-down and receptor-capture work uses magnetic beads.
How laboratories choose within a family
Three recurring decisions. Isoform and processing state: BNP versus NT-proBNP, apelin-13 versus apelin-36, big-ET versus mature ET-1 — these are different analytes, and an assay calibrated for one will not report the other correctly. Species: rodent and human natriuretic peptide sequences diverge enough that a human-calibrated kit under-reports mouse samples; every catalog item states its species reactivity. Agonist versus antagonist fragment: CGRP(8–37), des-Arg bradykinin analogs and Ang-(1–7) are receptor tools, not substitutes for the parent peptide in quantitation. For sample-concentration questions, a kit is almost always faster than assembling antibody, tracer and standards.
Handling notes for this topic
Two properties dominate practical handling. Several cardiovascular peptides are disulfide-cyclised — endothelin-1 carries two disulfide bridges, ANP and urotensin II one each — and reducing conditions or thiol-containing buffers will destroy activity. Others are rapidly degraded in plasma, which is why stable precursor fragments such as NT-proBNP and copeptin became the preferred analytes; sample collection with protease inhibitors matters as much as reagent choice. Otherwise the standard workflow applies: sealed lyophilised vials at −20 °C, single-use aliquots after reconstitution, no repeated freeze–thaw. See the storage guide, the aliquoting guide and the COA guide for verifying peptide content.
Where to go next
Browse the full cardiovascular topic, the heart and vasculature hub, or the natriuretic peptide system hub. Adjacent guides cover the diabetes and metabolism section, which shares apelin and adrenomedullin, and the cancer section for the angiogenesis families.