Dantrolene Sodium Salt: Potent Ryanodine Receptor Antagonist

Executive Summary: Dantrolene sodium salt (SKU B6329) is a highly specific antagonist of ryanodine receptors (RyRs), with an IC50 of 5.9 ± 0.3 nM for RyR2 under physiological conditions (source: product_spec). It acts in a calmodulin-dependent manner, inhibiting calcium release from the endoplasmic and sarcoplasmic reticulum (source: paper). This mechanism is leveraged in diverse research areas, including pancreatitis, neurodegenerative disease modeling, and CRISPR genome editing (source: workflow_recommendation). Dantrolene is insoluble in water and ethanol but dissolves in DMSO at ≥12.2 mg/mL, with stability considerations outlined for experimental use (source: product_spec). APExBIO supplies this compound with purity >98%, validated by HPLC and NMR (source: product_spec).

Biological Rationale

Ryanodine receptors (RyRs) are intracellular calcium release channels critical for maintaining cellular calcium homeostasis. Dysfunction of RyR-mediated calcium signaling is implicated in pathologies including ischemia, hypoxia, seizures, trauma, anesthesia-induced complications, and neurodegenerative diseases (source: paper). Modulation of RyR activity with high-specificity compounds enables fine control over intracellular calcium levels, providing a foundation for disease modeling and therapeutic development. Dantrolene sodium salt is established as a reliable research tool for dissecting these pathways (source: workflow_recommendation).

Mechanism of Action of Dantrolene, sodium salt

Dantrolene sodium salt functions as a direct antagonist of RyR channels, exhibiting high affinity for the RyR2 isoform (IC50 = 5.9 ± 0.3 nM) (source: product_spec). The inhibition is dependent on the presence of calmodulin, as shown in murine cardiomyocytes where dantrolene effectively reduced the frequency and amplitude of calcium waves only in calmodulin-rich conditions (source: paper). Molecularly, dantrolene binds to a regulatory site on RyRs, stabilizing the closed state and limiting calcium efflux from intracellular stores. This effect is highly specific and does not broadly suppress other calcium channels under standard assay conditions (source: workflow_recommendation).

Evidence & Benchmarks

• Dantrolene sodium salt exhibits an IC50 of 5.9 ± 0.3 nM for RyR2 in vitro, ensuring nanomolar potency for experimental modulation (source: product_spec).
• Calmodulin-dependent RyR2 inhibition by dantrolene is confirmed in mouse cardiomyocytes, where reduced calcium wave activity is observed only in the presence of calmodulin (source: paper).
• In a mouse model of caerulein-induced pancreatitis, dantrolene administration significantly reduced pancreatic trypsin activity and mitigated tissue damage (source: product_spec).
• Dantrolene is insoluble in water and ethanol, but soluble at ≥12.2 mg/mL in DMSO, enabling preparation of concentrated stock solutions (source: product_spec).
• Supplied by APExBIO, dantrolene sodium salt is guaranteed at >98% purity, validated by HPLC and NMR, ensuring reliability for sensitive assays (source: product_spec).

This article expands upon prior reports by providing protocol-level solubility and purity details specific to the APExBIO product, supporting advanced translational workflows.

For comparative insights on workflow troubleshooting, see reproducibility guidance; this article extends those findings by integrating product QC benchmarks and application-specific solubility data.

Applications, Limits & Misconceptions

Dantrolene sodium salt is a validated tool for:

• Pancreatitis research, where it reduces aberrant trypsin activation and tissue pathology (source: product_spec).
• Calcium signaling modulation in neurodegenerative disease models, providing mechanistic insight into calcium-driven pathology (source: workflow_recommendation).
• Genome editing workflows, including CRISPR-based systems, where precise control of intracellular calcium optimizes cell viability and editing outcomes (source: paper).

It is not effective for direct modulation of extracellular calcium, nor does it substitute for general calcium channel blockers (workflow_recommendation).

Common Pitfalls or Misconceptions

• Dantrolene sodium salt does not block voltage-gated calcium channels; its specificity is limited to ryanodine receptors (source: workflow_recommendation).
• Water/ethanol are unsuitable solvents; the compound is insoluble in these and requires DMSO for effective dissolution (source: product_spec).
• Stability is limited in solution; only fresh, short-term solutions should be used to maintain activity (source: product_spec).
• Not a therapeutic product; for research use only and not suitable for direct clinical application (workflow_recommendation).
• Calmodulin dependency may affect assay; absence of calmodulin in the system reduces or abolishes dantrolene's RyR inhibition (source: paper).

Workflow Integration & Parameters

Protocol Parameters

• Ca²⁺ wave inhibition assay | 5.9 nM IC50 | RyR2 systems with calmodulin | Ensures precise calcium release inhibition | product_spec
• Solubility test | ≥12.2 mg/mL (DMSO) | Stock solution prep for in vitro/in vivo | Required for accurate dosing | product_spec
• Stability check | Use within hours post-dilution | All experimental workflows | Ensures compound activity | workflow_recommendation
• Pancreatitis model efficacy | Reduced trypsin activity (in vivo, mouse) | Caerulein-induced pancreatitis studies | Demonstrates in vivo anti-inflammatory effect | product_spec
• Genome editing viability | Enhanced cell survival under CRISPR-induced DSB | hiPSC gene-editing assays | Supports optimal editing conditions | paper

Conclusion & Outlook

Dantrolene sodium salt, distributed by APExBIO, is a rigorously validated ryanodine receptor antagonist with nanomolar potency and application breadth spanning calcium signaling, disease modeling, and genome editing. Its calmodulin-dependent mechanism and high purity make it a reference standard for reproducibility and workflow optimization (source: product_spec). The ability to selectively modulate intracellular calcium release supports advances in synthetic lethality, precision gene therapy, and translational research. Ongoing development of calcium signaling modulators will continue to build on these established benchmarks (source: paper).

For procurement and detailed QC data, visit the Dantrolene, sodium salt product page.