Aminocaproic acid targets plasminogen and plasmin, the key enzymes involved in fibrinolysis. It acts as a competitive inhibitor of plasminogen activation, binding to the lysine-binding sites of plasminogen and preventing its binding to fibrin. This inhibits the activation of plasminogen to plasmin and the subsequent degradation of fibrin clots. Aminocaproic acid also directly inhibits plasmin activity at higher concentrations.

6-Aminocaproic acid, with an effective concentration of 61.5 μg/mL, inhibits fibrinolysis in Asian elephant plasma, ranging from 20-180 μg/mL [2]. 6-Using PEGylated indocyanine green, aminocaproic acid can be employed as a hydrophobic linker to enhance near-infrared fluorescence imaging and photothermal cancer therapy [4].
In vitro, Aminocaproic acid has been shown to inhibit plasminogen activation and plasmin activity in a concentration-dependent manner. It blocks the binding of plasminogen to fibrin, preventing fibrinolysis. The compound's antifibrinolytic activity has been demonstrated in various in vitro assays, including clot lysis assays and chromogenic substrate assays. Aminocaproic acid is a potent inhibitor of fibrinolysis.

6-Aminocaproic acid (20-100 mg/kg; single oral dosage) reduces fibrinolysis at all levels studied in dogs [3]. 6-Aminocaproic acid (20-100 mg/kg; single oral dose) is rapidly absorbed (Tmax=1 hour) and rapidly excreted in dogs [3].
In vivo, Aminocaproic acid has been shown to be effective in reducing bleeding in patients with elevated fibrinolytic activity. Clinical studies have demonstrated its efficacy in reducing blood loss and transfusion requirements in patients undergoing cardiac surgery, liver transplantation, and other procedures. Aminocaproic acid is also used to treat bleeding in patients with hematological disorders.

In vitro enzyme inhibition assays for Aminocaproic acid typically involve measuring the activity of plasmin or the activation of plasminogen in the presence of varying concentrations of the compound. The enzyme is incubated with its substrate and Aminocaproic acid, and the enzymatic activity is measured using chromogenic or fluorogenic substrates. The IC50 value for inhibition of the enzyme is determined from dose-response curves.

In vitro cell-based studies with Aminocaproic acid typically involve cultured cells, such as endothelial cells or blood cells. Cells are treated with Aminocaproic acid at various concentrations. The effect of the compound on fibrinolysis, cell adhesion, and cell migration can be evaluated. The compound's effect on cell viability can also be assessed.

In vivo animal studies with Aminocaproic acid are typically conducted in rodent or canine models of bleeding. The compound is administered orally or intravenously. The effect of Aminocaproic acid on bleeding time, blood loss, and clot stability is assessed. The compound's efficacy in reducing bleeding in models of surgery, trauma, or hematological disorders is evaluated. Pharmacokinetic studies are performed by measuring compound concentrations in plasma.

Absorption, Distribution and Excretion
Rapid absorption after oral administration. In adults, oral absorption appears to be a zero-order process, with an absorption rate of 5.2 g/h. The mean absorption delay is 10 minutes. Complete absorption is achieved after a single oral dose of 5 g (F=1). Regardless of whether aminocaproic acid is administered orally or intravenously, renal excretion is the primary route of elimination. 23.1 ± 6.6 L 169 mL/min Aminocaproic acid is well absorbed orally… This drug is primarily excreted unchanged in the urine, reaching peak plasma concentrations approximately 2 hours after a single oral dose. Metabolisms/Metabolites 65% of the dose is excreted unchanged in the urine, and 11% is excreted as the metabolite adipic acid. Biological Half-Life The terminal elimination half-life is approximately 2 hours.
Aminocaproic acid is a well-characterized drug with established pharmacokinetic properties. Following oral administration, it is rapidly absorbed from the gastrointestinal tract. Aminocaproic acid has a bioavailability of approximately 100%. It is not extensively metabolized and is primarily excreted unchanged in the urine. The elimination half-life is approximately 2 hours. The drug is not significantly protein-bound.

Interactions
Plasminogen activators, such as streptokinase and urokinase, are used to treat thromboembolic diseases. ...Aminocaproic acid can antagonize the thrombolytic effects of these drugs...
Aminocaproic acid is a clinically approved drug with a well-established safety profile. The most common adverse effects are mild and include nausea, vomiting, diarrhea, and abdominal pain. Rare but serious adverse effects include thrombotic events, such as deep vein thrombosis and pulmonary embolism. Aminocaproic acid should be used with caution in patients with a history of thrombotic disease.

[1]. Epsilon-aminocaproic acid (EACA). Semin Thromb Hemost. Summer 1978;5(1):27-40.

[2]. EFFECT OF ε-AMINOCAPROIC ACID ON FIBRINOLYSIS IN PLASMA OF ASIAN ELEPHANTS (ELEPHAS MAXIMUS). J Zoo Wildl Med. 2016 Jun;47(2):397-404.

[3]. Effect of aminocaproic acid on clot strength and clot lysis of canine blood determined by use of an in vitro model of hyperfibrinolysis. Am J Vet Res. 2016 Nov;77(11):1258-1265.

[4]. 6-Aminocaproic acid as a linker to improve near-infrared fluorescence imaging and photothermal cancer therapy of PEGylated indocyanine green. Colloids Surf B Biointerfaces. 2021 Jan;197:111372.

6-Aminohexanoic acid is an ε-amino acid composed of hexanoic acid with an amino substituent attached at the C-6 position. It is used to control postoperative bleeding and to treat overdose of the thrombolytic agents streptokinase and tissue plasminogen activator. It has antifibrinolytic, hematologic, and metabolite-related effects. It is an ε-amino acid and an ω-amino fatty acid. Functionally, it is related to hexanoic acid. It is the conjugate acid of 6-aminohexanoate. It is a zwitterionic tautomer of 6-aminohexanoic acid. It is an antifibrinolytic agent that works by inhibiting plasminogen activator, which has fibrinolytic properties. Aminohexanoic acid is an antifibrinolytic agent. The physiological effects of aminohexanoic acid are achieved by reducing fibrinolysis. Aminohexanoic acid has been reported in Daphnia pulex, Arabidopsis thaliana, and other organisms with relevant data. Aminohexanoic acid is a synthetic lysine derivative with antifibrinolytic activity. Aminocaproic acid competitively inhibits plasminogen activation, thereby reducing the conversion of plasminogen to plasmin (fibrinolysin). Plasmin is an enzyme that degrades fibrin clots, as well as fibrinogen and other plasma proteins, including procoagulant factors V and VIII. Aminocaproic acid competitively inhibits the conversion of plasminogen to plasmin by plasminogen activators. It directly inhibits the proteolytic activity of plasmin, but at a higher dose than is required to reduce plasmin production. Aminocaproic acid is used to treat and prevent bleeding, including bleeding caused by hyperfibrinolysis and postoperative bleeding. It is an antifibrinolytic drug that works by inhibiting plasminogen activators, which have fibrinolytic properties. Indications: For the treatment of excessive postoperative bleeding. FDA Label: Mechanism of Action: Aminocaproic acid reversibly binds to the kringle domain of plasminogen, blocking the binding of plasminogen to fibrin and its activation into plasmin. Because plasmin is not activated, fibrinolysis is reduced. This ultimately reduces postoperative bleeding. Studies have shown that elevated plasma lipoprotein(a) levels increase the risk of vascular disease. Lipoprotein(a) consists of two components: apolipoprotein B-100 and apolipoprotein(a). Aminocaproic acid may alter the conformation of apolipoprotein(a), thereby changing its binding properties and potentially preventing lipoprotein(a) formation. It is a competitive inhibitor of plasminogen activator, with a weaker inhibitory effect on plasminogen. Therefore, it inhibits the formation of plasminogen, an enzyme that destroys fibrinogen, fibrin, and other coagulation components. The intermolecular interactions between plasminogen and plasminogen with ε-aminocaproic acid (I) were investigated using microcalorimetry, UV spectroscopy, and IR spectroscopy to determine the mechanism of fibrinolysis inhibition. At low doses, the inhibitory effect is mainly attributed to blocking the activation phase of plasminogen; while at high concentrations, the therapeutic effect is also achieved by inactivating the enzymatic activity of plasminogen.

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Therapeutic Uses
Antifibrinolytic Drugs
…For the treatment of surgeries or diseases that enhance fibrinolysis…coronary artery bypass grafting, post-vena cava shunt, major thoracic surgery, post-prostatectomy hematuria…non-surgical hematuria, leukemia, metastatic prostate cancer, cirrhosis and other liver diseases, eclampsia, intrauterine fetal death, amniotic fluid embolism, and placental abruption. This drug is ineffective against thrombocytopenia, hyperheparinemia, or bleeding caused by other coagulation disorders or vascular damage.
When administered intravenously…it should be diluted with an isotonic solution or glucose solution and injected slowly. The patient's condition should be reassessed 8 hours after treatment.
…It is the specific antidote for fibrinolytic drug overdose. ...
For more complete data on the therapeutic uses of 6-aminocaproic acid (9 in total), please visit the HSDB record page.

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Drug Warnings
Rapid intravenous injection should be avoided to prevent hypotension, bradycardia, and other arrhythmias.
...It is teratogenic in animals and therefore contraindicated during the first two gestational periods. It should only be used in late pregnancy when absolutely necessary.
Using aminocaproic acid in patients with disseminated intravascular coagulation (DIC) may lead to serious and even fatal thrombosis.Most specialists do not use aminocaproic acid to treat \"fibrinolytic\" bleeding unless there is conclusive evidence that DIC is not the underlying cause.
When using aminocaproic acid during surgery, care must be taken to remove thrombi from body cavities, as the drug will remain at high concentrations in the thrombus, thus inhibiting its physiological dissolution.
The incidence of thrombotic events due to drug inhibition of the fibrinolytic system is unclear, but it may be particularly high in patients with a potential predisposition to thrombosis. Thrombosis.

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Pharmacodynamics
Aminocaproic acid is an antifibrinolytic drug, a derivative of the amino acid lysine. The fibrinolytic inhibitory effect of aminocaproic acid is primarily exerted by inhibiting plasminogen activator, and secondarily by inhibiting plasminase activity.
Aminocaproic acid may be a potential drug for preventing vascular disease because it may inhibit the formation of lipoprotein(a), a risk factor for vascular disease.
Aminocaproic acid is an antifibrinolytic agent used to treat and prevent excessive bleeding from fibrinolysis. It is available in various formulations, including tablets and injectable solutions. Aminocaproic acid is marketed under various brand names. It is a prescription medication and is not available over-the-counter.

C6H13NO2

131.1729

131.094

60-32-2

6-Aminocaproic acid-d6;1228656-08-3;6-Aminocaproic acid hydrochloride;4321-58-8;6-Aminocaproic acid-d10;461432-51-9

564

White to off-white solid powder

1.0±0.1 g/cm3

255.6±23.0 °C at 760 mmHg

207-209 °C (dec.)(lit.)

108.4±22.6 °C

0.0±1.1 mmHg at 25°C

1.467

-0.11

2

3

5

9

83.1

0

SLXKOJJOQWFEFD-UHFFFAOYSA-N

InChI=1S/C6H13NO2/c7-5-3-1-2-4-6(8)9/h1-5,7H2,(H,8,9)

6-aminohexanoic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

H2O : ≥ 50 mg/mL (~381.18 mM)
DMSO : ~1 mg/mL (~7.62 mM)

Solubility in Formulation 1: 25 mg/mL (190.59 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.

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 (Please use freshly prepared in vivo formulations for optimal results.)