Proteinase Functional Systems and Regulatory Logic in Hemostasis, Fibrinolysis, and Vascular Homeostasis

Hemostasis, fibrinolysis, and vascular homeostasis are not three isolated processes, but rather a continuous reaction system jointly maintained by multiple classes of proteases and their inhibitory networks. Coagulation-related serine proteases mediate rapid sealing after injury, the fibrinolytic protease system constrains and clears thrombi, and vascular wall-associated regulatory proteases participate in endothelial integrity, the threshold for platelet adhesion, matrix renewal, and inflammatory coupling. Understanding this system requires analysis within a unified framework of “zymogen activation–substrate cleavage–inhibitory feedback–spatial localization–pathological amplification.”

 

Keywords: proteases; hemostasis; fibrinolysis; thrombin; plasmin; activated protein C; ADAMTS13; vascular homeostasis; endothelial function; thrombosis

 

I. Hemostasis, Fibrinolysis, and Vascular Homeostasis Form a Continuous Regulatory System

1.1 The essence of the hemostatic system is a locally confined proteolytic network

(1) The hemostatic response depends on zymogen cascade amplification

Most coagulation factors exist as inactive zymogens and are converted into active serine proteases through limited proteolysis, thereby amplifying local coagulation signals step by step. This cascade structure gives the post-injury response both high sensitivity and strong spatial restriction.

(2) Hemostasis is not merely a process of clot formation

True physiological hemostasis requires not only fibrin generation and platelet plug formation, but also confinement of the reaction to the site of injury, followed by timely transition into phases of restriction, clearance, and reconstruction after vascular repair. If coagulation amplification occurs without adequate braking, pathological thrombosis will result.

 

1.2 The fibrinolytic system is responsible for clot remodeling and clearance

(1) Fibrinolysis is the enzymatic counter-regulation of the end products of coagulation

The end product of the coagulation system is a stable fibrin network, whereas the fibrinolytic system degrades fibrin through plasmin, thereby limiting thrombus size and progressively removing the clot after repair.

(2) The fibrinolytic system is not equivalent to simple “thrombolysis”

Under physiological conditions, the more important role of fibrinolysis is to limit clot extension, maintain microcirculatory patency, and ensure reopening of the vascular lumen, rather than to degrade all coagulation products without restriction.

 

1.3 Vascular homeostasis depends on sustained low-level regulation by protease networks

(1) The vascular wall is the spatial platform for protease reactions

Endothelial cells, subendothelial matrix, platelet membrane surfaces, and circulating inhibitory molecules together determine where protease reactions occur and how efficiently they proceed. The same enzymatic activity can produce entirely different biological consequences in different spatial settings.

(2) Loss of homeostasis often manifests as a shift in protease activity thresholds

When coagulation proteases are excessively activated, fibrinolytic protease activity is insufficient, or vascular wall regulatory proteases become abnormal, the system may shift from physiological hemostasis toward bleeding tendency, thrombotic tendency, or microangiopathic injury.

 

II. The Coagulation Protease Cascade Constitutes the Main System of the Hemostatic Response

2.1 The initiation phase is driven by the tissue factor-related pathway

(1) Exposure of tissue factor triggers extrinsic initiation

After vascular injury, tissue factor is exposed to circulating blood and forms an initiation complex with factor VII/VIIa, promoting activation of factor X and factor IX and thereby initiating thrombin generation.

(2) The significance of extrinsic initiation lies in rapidly establishing the coagulation threshold

The main function of this stage is not to generate a large amount of fibrin at once, but to rapidly establish the initial thrombin signal sufficient to drive subsequent intrinsic amplification.

 

2.2 The amplification phase depends on the intrinsic protease cascade

(1) Factors XIa, IXa, and VIIIa drive sustained amplification

After initial thrombin formation, factors XI, IX, and VIII further participate in amplification loops, promoting additional conversion of factor X to Xa and thereby markedly increasing the rate of thrombin generation.

(2) Phospholipid surfaces determine amplification efficiency

Activated platelets provide membrane surfaces enriched in anionic phospholipids, allowing efficient assembly of the tenase and prothrombinase complexes. Accordingly, coagulation depends not only on proteases themselves, but also on the membrane microenvironment.

 

2.3 The terminal phase is driven by thrombin-mediated fibrin formation and stabilization

(1) Thrombin cleaves fibrinogen to generate fibrin

Thrombin is the core effector protease of the coagulation system, and its direct substrate is fibrinogen. After fibrin monomers are formed, they further polymerize to create the structural scaffold of the clot.

(2) Thrombin simultaneously amplifies upstream reactions

In addition to cleaving fibrinogen, thrombin activates factors V, VIII, XI, and platelets, thereby forming a typical positive-feedback amplification structure. Its biological role therefore extends far beyond that of a single terminal enzyme.

 

2.4 Key members of the coagulation protease system

Table 1. Key Proteases in Hemostasis, Fibrinolysis, and Vascular Homeostasis and Their Functional Positioning

 

Protease	System	Major Substrates or Targets	Main Functional Positioning	Significance in Homeostasis
Coagulation factor VIIa	Coagulation initiation	Tissue factor, factor X, factor IX	Extrinsic coagulation initiation	Establishes the initial coagulation threshold after injury
Coagulation factor IXa	Coagulation amplification	Factor X	Intrinsic amplification	Enhances local coagulation efficiency
Coagulation factor Xa	Coagulation amplification and terminal phase	Prothrombin	Promotes thrombin generation	Determines the rate of thrombin generation
Thrombin (IIa)	Core coagulation effector	Fibrinogen, factors V, VIII, XI, PAR receptors	Fibrin formation and positive-feedback amplification	Determines the intensity and extent of hemostasis
Activated protein C (APC)	Anticoagulant regulation	Factors Va and VIIIa	Restrains coagulation amplification	Prevents excessive thrombus formation
Tissue-type plasminogen activator (tPA)	Fibrinolytic activation	Plasminogen	Generates plasmin	Promotes fibrin degradation
Urokinase-type plasminogen activator (uPA)	Fibrinolysis and tissue remodeling	Plasminogen	Promotes local proteolysis and migration-associated fibrinolysis	Participates in vascular wall remodeling
Plasmin	Core fibrinolytic effector	Fibrin, fibrinogen, and others	Clot degradation	Maintains vascular recanalization and restricts thrombus extension
ADAMTS13	Regulation of vascular homeostasis	Ultra-large VWF multimers	Cleaves VWF	Reduces the risk of microvascular thrombosis

 

III. Thrombin Is the Central Protease Connecting Hemostasis, Inflammation, and Vascular Signaling

3.1 Thrombin has a broad substrate spectrum

(1) Thrombin does not act only on fibrinogen

Thrombin can cleave fibrinogen, activate factors V, VIII, XI, and XIII, and promote platelet activation. It is therefore not merely a single terminal enzyme, but the central amplification node of the entire hemostatic network.

(2) Substrate selection is regulated by the local environment

The reaction spectrum of thrombin is jointly influenced by membrane surfaces, cofactors, substrate concentration, and receptor localization. In the free state, membrane-bound state, and regulatory protein-bound state, thrombin does not produce identical functional outputs.

 

3.2 Thrombin can affect the vascular wall through receptor-mediated mechanisms

(1) PAR receptor cleavage is an important mode of signal output

Thrombin can influence endothelial permeability, platelet reactivity, smooth muscle cell behavior, and inflammation-related gene expression by cleaving members of the protease-activated receptor family. This makes thrombin a key protease with both hemostatic and signaling functions.

(2) Thrombin signaling is bidirectional

At different concentrations, in different receptor contexts, and across different cell types, thrombin can either promote barrier disruption and inflammatory amplification or, under certain regulatory conditions, participate in repair and maintenance of homeostasis.

 

3.3 The pathological significance of thrombin lies in excessive or mislocalized activation

(1) Excessive thrombin generation drives thrombosis

If thrombin generation exceeds that required for local injury repair, fibrin formation and platelet activation will expand further, resulting in venous thrombosis, arterial thrombosis, or microthrombus formation.

(2) Insufficient thrombin generation results in hemostatic failure

If thrombin generation is inadequate, both fibrin formation and platelet stabilization are compromised, which may manifest as delayed hemostasis, fragile clot formation, and persistent oozing.

 

IV. Natural Anticoagulant Protease Regulatory Systems Restrict the Spillover of Coagulation Reactions

4.1 The activated protein C pathway is the key axis of coagulation braking

(1) The thrombin-thrombomodulin complex alters substrate preference

After binding thrombomodulin on the endothelial surface, thrombin shifts its substrate spectrum from a procoagulant direction toward activation of protein C. This transformation illustrates how the same protease can fulfill entirely different physiological functions depending on its molecular pairing context.

(2) Activated protein C cleaves factors Va and VIIIa

APC limits the continued expansion of the coagulation cascade by inactivating the essential amplification cofactors Va and VIIIa, thereby reducing the efficiency of further Xa and thrombin generation.

 

4.2 The significance of the anticoagulant system lies in spatial and temporal restriction

(1) Spatial restriction

Anticoagulant regulation confines coagulation primarily to the local site of injury, preventing unnecessary zymogen amplification in regions of normal blood flow.

(2) Temporal restriction

Once vascular repair has been initiated, the anticoagulant system helps shorten the duration of the coagulation response, allowing hemostasis to transition from amplification to stabilization and clearance.

 

4.3 Abnormalities in the anticoagulant protease axis can lead to bidirectional pathological outcomes

(1) Insufficient braking leads to thrombotic tendency

If APC axis activity is insufficient, the coagulation amplification phase is more likely to persist, increasing the risk of thrombosis.

(2) Excessive braking or cofactor insufficiency leads to bleeding tendency

If coagulation amplification is excessively suppressed before it is adequately established, fibrin generation may become insufficient and hemostatic failure may result.

 

V. The Fibrinolytic Protease System Is Responsible for Clot Restriction, Remodeling, and Clearance

5.1 The core of the fibrinolytic system is plasminogen activation

(1) tPA is a physiological fibrin-dependent activator

Tissue-type plasminogen activator primarily promotes conversion of plasminogen to plasmin on the fibrin surface, and therefore its activity exhibits a certain clot dependence and spatial selectivity.

(2) uPA is more strongly associated with local tissue proteolytic environments

In addition to participating in fibrinolysis, urokinase-type plasminogen activator is also associated with cell migration, tissue remodeling, and local proteolysis in the vascular wall. Its biological scope is therefore broader than that of tPA.

 

5.2 Plasmin is the core effector protease for fibrin degradation

(1) Plasmin cleaves fibrin

Plasmin directly degrades cross-linked and non-cross-linked fibrin, causing reduction in clot volume, loosening of structure, and eventual clearance. Its activity determines whether the clot can be constrained within an appropriate range.

(2) The plasmin system has both amplification potential and risk

Once plasmin is formed, it can further promote expansion of local proteolysis. Its generation and inhibition must therefore be tightly controlled. Excessive fibrinolysis may cause rebleeding, whereas insufficient fibrinolysis allows thrombi to persist.

 

5.3 The significance of the fibrinolytic system in homeostasis is not merely “clot lysis”

(1) Restriction of excessive clot extension

The most direct physiological role of fibrinolysis is to prevent an already formed clot from continuing to extend outward and obstruct blood flow.

(2) Support of post-repair vascular recanalization

After vascular wall repair progresses, the fibrinolytic system removes excess fibrin and restores blood flow channels, thereby constituting an essential part of the homeostatic closed loop.

 

VI. Vascular Wall-Associated Proteases Regulate the Hemostatic Threshold and Microcirculatory Stability

6.1 ADAMTS13 is a key enzyme linking VWF metabolism to microthrombotic risk

(1) ADAMTS13 cleaves ultra-large VWF multimers

Ultra-large VWF multimers released by the endothelium possess very strong platelet-adhesive capacity. ADAMTS13 reduces the tendency toward abnormal platelet aggregation by cleaving them into shorter forms.

(2) ADAMTS13 deficiency can cause microvascular thrombosis

When ADAMTS13 activity is insufficient, ultra-large VWF multimers persist, markedly increasing the risk of platelet thrombus formation in the microcirculation, potentially leading to microangiopathic hemolysis and impaired organ perfusion.

 

6.2 Proteolysis in the vascular wall is tightly coupled to endothelial homeostasis

(1) The endothelial surface determines the platform for protease reactions

Endothelial cells not only provide anticoagulant-related molecules, but also regulate protease localization through surface receptors, matrix-binding sites, and local secretion, thereby enabling spatial stratification of coagulation, fibrinolysis, and anticoagulant reactions.

(2) Vascular wall protease regulation affects barrier function and inflammation

Certain proteases can alter endothelial junctional status, leukocyte adhesion, and platelet response thresholds through receptor cleavage and matrix remodeling. Accordingly, disruption of vascular homeostasis is often accompanied by simultaneous shifts in hemostasis and inflammation.

 

VII. Protease Network Imbalance and Major Pathological States

7.1 Hemorrhagic states

(1) Insufficient generation of coagulation proteases

When thrombin generation is impaired, or when its upstream cascade amplification is insufficient, both fibrin formation and clot stabilization are compromised.

(2) Excessive fibrinolysis

If the fibrinolytic system is overactivated, already formed hemostatic clots may be degraded prematurely, leading to persistent oozing or delayed hemorrhage.

 

7.2 Thrombotic states

(1) Excessive amplification of coagulation proteases

Sustained generation of Xa and thrombin can shift the local hemostatic response toward pathological thrombus formation.

(2) Insufficient fibrinolysis or insufficient VWF cleavage

When fibrinolytic clearance capacity declines or ADAMTS13 activity is inadequate, formed clots and microthrombi become more difficult to limit and remove.

 

7.3 States related to disruption of vascular homeostasis

(1) Endothelial dysfunction

When anticoagulant and regulatory capacity on the endothelial surface declines, protease networks are more likely to shift toward procoagulant and proinflammatory directions.

(2) Breakdown of microcirculatory proteolytic balance

In inflammation, infection, ischemia-reperfusion, and immune-mediated diseases, proteases involved in hemostasis, fibrinolysis, and vascular wall regulation often become simultaneously dysregulated, producing complex microvascular pathological phenotypes.

 

VIII. Key Pathways, Targets, and Analytical Readouts in Research

8.1 Main research pathways

(1) Coagulation protease cascade pathway

The focus is on the dynamic relationships among extrinsic initiation, intrinsic amplification, thrombin generation, and fibrin formation.

(2) Fibrinolytic activation and inhibition pathways

The focus is on tPA/uPA-mediated plasmin generation, fibrin degradation efficiency, and mechanisms that restrain fibrinolysis.

(3) Coagulation-endothelial signaling coupling pathways

The focus is on the effects of thrombin, APC, and related receptor signaling on endothelial barrier function, inflammation, and microthrombus formation.

(4) The VWF-ADAMTS13 axis

The focus is on VWF multimer metabolism and changes in platelet adhesion thresholds under high-shear conditions.

 

8.2 Key research targets

(1) Core coagulation targets

These include Xa, thrombin, IXa, and XIa, and are mainly used to study coagulation amplification and antithrombotic intervention.

(2) Core fibrinolytic targets

These include tPA, uPA, and plasmin, and are mainly used to study fibrin clearance and thrombus remodeling.

(3) Core regulatory targets

These include the APC pathway and ADAMTS13, and are mainly used to study coagulation braking, endothelial protection, and microcirculatory homeostasis.

 

8.3 Common analytical readouts

(1) Coagulation function indices

① Prothrombin time.

② Activated partial thromboplastin time.

③ Thrombin generation curve.

④ Fibrinogen level.

⑤ Factor Xa or thrombin activity readout.

(2) Fibrinolytic function indices

① Plasminogen level.

② tPA or uPA activity.

③ D-dimer.

④ Fibrin degradation products.

⑤ Clot lysis time.

(3) Vascular homeostasis-related indices

① VWF antigen or activity.

② ADAMTS13 activity.

③ Endothelial injury markers.

④ Platelet activation indices.

⑤ Microvascular perfusion-related readouts.

Table 2. Pathways, Targets, and Analytical Readouts of Proteases in Studies of Hemostasis, Fibrinolysis, and Vascular Homeostasis

 

Research Direction	Main Pathway	Key Targets	Common Analytical Readouts
Hemostatic initiation and coagulation amplification	Extrinsic coagulation initiation, intrinsic amplification, thrombin generation	FVIIa, FIXa, FXa, thrombin	PT, APTT, thrombin generation assay, fibrinogen
Fibrin formation and clot stabilization	Thrombin-fibrinogen-factor XIII axis	Thrombin, factor XIIIa	Fibrin formation rate, clot strength, clot structure analysis
Fibrinolytic activation and clearance	tPA/uPA-plasminogen-plasmin axis	tPA, uPA, plasmin	D-dimer, FDP, clot lysis time, plasmin activity
Anticoagulant regulation	Thrombin-thrombomodulin-APC axis	APC, Va, VIIIa	APC activity, protein C-related readouts, degree of thrombin generation suppression
Vascular homeostasis and microthrombosis	VWF-ADAMTS13 axis, endothelial surface regulation	ADAMTS13, VWF	ADAMTS13 activity, VWF antigen/activity, platelet adhesion-related indices

 

IX. Aladdin-Related Products

9.1 Products Related to Coagulation Initiation, Amplification, and Thrombin Generation

 

Catalog No.	Name	Grade and Purity	Suitable Research Direction/Application
EJ1513852	Human Coagulation Factor Ⅶ (FⅦ) ELISA Kit	BioReagent	Evaluation of extrinsic coagulation initiation; studies on tissue factor-related coagulation thresholds
EJ1514250	Human Activated Coagulation Factor VIIa(FVIIa) ELISA Kit	BioReagent	Detection of FVIIa activation levels; studies on coagulation initiation intensity
H1442061	Human Factor VIIa		Enzymology studies of the extrinsic initiation complex; construction of coagulation initiation models
EJ1513848	Human Coagulation Factor Ⅸ(FⅨ) ELISA Kit	BioReagent	Detection of intrinsic amplification pathways; studies on FIX-related coagulation efficiency
EJ1513849	Human Coagulation Factor Ⅹ (F10) ELISA Kit	BioReagent	Detection of FX levels; evaluation of Xa generation potential
F1445139	Factor Xa		Enzymatic reaction studies of Xa; validation of the key pre-thrombin-generation node
EJ1513854	Human Coagulation Factor Ⅺ (FⅪ) ELISA Kit	BioReagent	Detection of intrinsic amplification pathways; studies on FXI-related amplification
EJ1513850	Human Coagulation Factor Ⅺa(FⅪa) ELISA Kit	BioReagent	Detection of FXIa activation levels; evaluation of coagulation amplification status
H1443844	Human Factor XIa		FXIa enzymology studies; construction of intrinsic coagulation amplification models
EJ1513855	Human Coagulation Factor Ⅻ(FⅫ) ELISA Kit	BioReagent	Studies on contact activation; evaluation of upstream coagulation triggering
H1430415	Human Factor XIIa Beta		Proteolysis studies in the contact pathway; construction of FXIIa-related activation models
EJ1513847	Human Coagulation Factor Ⅱ(FⅡ) ELISA Kit	BioReagent	Detection of prothrombin levels; evaluation of terminal coagulation generation potential
EJ1513856	Human Prothrombin Fragment 1+2 (F1+2) ELISA Kit	BioReagent	Readout of prothrombin activation; evaluation of in vivo thrombin generation
EJ1513857	Human Thrombin/antithrombin Complex(TAT) ELISA Kit	BioReagent	Readout of thrombin generation coupled with anticoagulant feedback; evaluation of hypercoagulable states
H1510083	Human Thrombin ELISA Kit	BioReagent	Detection of thrombin levels; studies on hemostatic intensity and thrombotic tendency
T754968	Thrombin	Bioactive,ActiBioPure™,Native,High Performance,EnzymoPure™,from human plasma; 400-1000 NIH U/mg protein	Studies on thrombin substrate cleavage; fibrin formation and PAR signaling research
EJ1511992	Rat Coagulation Factor Ⅱ(FⅡ) ELISA Kit	BioReagent	Detection of rat prothrombin; evaluation of coagulation status in animal models
EJ1511993	Rat Coagulation Factor Ⅶ(FⅦ) ELISA Kit	BioReagent	Studies on the rat extrinsic initiation pathway
EJ1511994	Rat Coagulation Factor IX (FⅨ) ELISA Kit	BioReagent	Studies on the rat intrinsic amplification pathway
EJ1511995	Rat Coagulation Factor X (FⅩ) ELISA Kit	BioReagent	Detection of rat FX levels; evaluation of Xa generation capacity
EJ1511991	Rat Coagulation Factor Ⅺ (FⅪ) ELISA Kit	BioReagent	Rat FXI-related amplification studies
EJ1511996	Rat Coagulation Factor Ⅻ (F12) ELISA Kit	BioReagent	Studies on rat contact pathway activation
EJ1511997	Rat Prothrombin Fragment 1+2 (F1+2) ELISA Kit	BioReagent	Readout of rat prothrombin activation; evaluation of in vivo coagulation generation
EJ1512674	Mouse Coagulation Factor Ⅱ(FⅡ) ELISA Kit	BioReagent	Detection of mouse prothrombin; studies in mouse hemostasis models
EJ1512676	Mouse Coagulation Factor Ⅶ(FⅦ) ELISA Kit	BioReagent	Studies on mouse extrinsic coagulation initiation
EJ1512678	Mouse Coagulation Factor Ⅸ (FⅨ) ELISA Kit	BioReagent	Studies on mouse intrinsic amplification pathways
EJ1512672	Mouse Coagulation Factor X (F10) ELISA Kit	BioReagent	Detection of mouse FX levels; Xa-related studies
EJ1512673	Mouse Coagulation Factor Ⅺ (FⅪ) ELISA Kit	BioReagent	Studies on the mouse FXI amplification pathway
EJ1512679	Mouse Coagulation Factor XII (FⅫ) ELISA Kit	BioReagent	Studies on mouse contact activation

 

9.2 Products Related to Fibrinolytic Activation, Clot Clearance, and Antifibrinolytic Regulation

 

Catalog No.	Name	Grade and Purity	Suitable Research Direction/Application
EJ1514062	Human Plasminogen Activator, Urokinase (uPA) ELISA Kit	BioReagent	Detection of uPA levels; studies on local proteolysis and fibrinolytic activation
H1509988	Human uPA/Urokinase ELISA Kit	BioReagent	Detection of uPA; evaluation of fibrinolytic activation capacity
EJ1514063	Human Plasminogen Activator, Urokinase Receptor (uPAR) ELISA Kit	BioReagent	Studies on the uPA-uPAR axis; evaluation of the local proteolytic environment in the vascular wall
H1510030	Human uPAR/CD87 ELISA Kit	BioReagent	Detection of uPAR/CD87; studies on cell migration and local fibrinolytic regulation
EJ1513938	Human Soluble Plasminogen Activator, Urokinase Receptor (suPAR) ELISA Kit	BioReagent	Detection of suPAR; evaluation of fibrinolysis-inflammation coupling status
EJ1514524	Human Plasmin (plasmin) ELISA Kit	BioReagent	Detection of plasmin levels; evaluation of clot degradation effects
EJ1514525	Human Plasminogen (Plg) ELISA Kit	BioReagent	Detection of plasminogen reserve; studies on fibrinolytic activation potential
np001029	Plasmin from Human Plasma	Native,EnzymoPure™,≥90%(SDS-PAGE),≥15 U/mg protein; Protein concentration: See COA	Studies on direct fibrin degradation by plasmin; construction of clot clearance and fibrinolytic effect models
np001028	Plasmin, Human Plasma, Lyophilized		Lyophilized human plasmin model; studies on clot degradation, fibrin clearance, and post-activation effects of plasmin
np001027	Plasminogen from human plasma	Bioactive, ActiBioPure™, High Performance, EnzymoPure™, ≥95%(SDS-PAGE), ≥120 U/mg protein	Studies on plasminogen reserve and activation potential; construction of tPA/uPA-mediated fibrinolysis initiation models
EJ1513398	Human Type 1 Tissue Plasminogen Activator Inhibitor (tPAI-1) ELISA Kit	BioReagent	Detection of PAI-1; evaluation of antifibrinolytic strength
H1509811	Human Serpin E1/PAI-1 ELISA Kit	BioReagent	Detection of PAI-1/Serpin E1; studies on fibrinolytic restriction status
EJ1514526	Human Plasminogen Activator Inhibitor 1 (PAI-1) ELISA Kit	BioReagent	Detection of PAI-1; evaluation of hypercoagulable/hypofibrinolytic phenotypes
EJ1514527	Human Plasminogen Activator Inhibitor 2 (PAI-2) ELISA Kit	BioReagent	Detection of PAI-2; studies on fibrinolytic inhibition and inflammation coupling
S287243	SK 216	≥98%(HPLC)	PAI-1 inhibition; studies on restoration of fibrinolysis and clot clearance capacity
EJ1512051	Rat Plasminogen Activator, Urokinase (uPA) ELISA Kit	BioReagent	Detection of rat uPA; studies on fibrinolytic activation in animal models
EJ1512202	Rat Plasmin(plasmin) ELISA Kit	BioReagent	Detection of rat plasmin; evaluation of clot degradation
EJ1512203	Rat Plasminogen (Plg) ELISA Kit	BioReagent	Detection of rat plasminogen; studies on fibrinolytic potential
EJ1512204	Rat Plasminogen Activator Inhibitor 1 (PAI-1) ELISA Kit	BioReagent	Detection of rat PAI-1; studies on hypofibrinolytic states
EJ1512205	Rat Plasminogen Activator Inhibitor 2 (PAI-2) ELISA Kit	BioReagent	Detection of rat PAI-2; studies on fibrinolytic regulation
EJ1512215	Rat Plasminogen Activator, Tissue (t-PA) ELISA Kit	BioReagent	Detection of rat tPA; studies on physiological fibrin-dependent fibrinolysis
EJ1511926	Rat α2-Antiplasmin (α2-AP) ELISA Kit	BioReagent	Evaluation of the rat antifibrinolytic system; studies on excessive or insufficient fibrinolysis
EJ1512759	Mouse Plasminogen Activator, Urokinase (uPA) ELISA Kit	BioReagent	Detection of mouse uPA; studies on fibrinolysis and tissue remodeling
EJ1512760	Mouse Plasminogen Activator, Urokinase Receptor (uPAR) ELISA Kit	BioReagent	Detection of mouse uPAR; studies on the proteolytic environment of the vascular wall
EJ1513012	Mouse Plasmin (Plasmin) ELISA Kit	BioReagent	Detection of mouse plasmin; studies on clot clearance
EJ1513013	Mouse Plasminogen (Plg) ELISA Kit	BioReagent	Detection of mouse plasminogen; evaluation of fibrinolytic reserve
EJ1513014	Mouse Plasminogen Activator Inhibitor 1 (PAI-1) ELISA Kit	BioReagent	Detection of mouse PAI-1; studies on hypofibrinolytic phenotypes
EJ1515203	Monkey Plasminogen Activator, Urokinase (uPA) ELISA Kit	BioReagent	Detection of monkey uPA; studies in non-human primate fibrinolytic models

 

9.3 Products Related to Anticoagulant Regulation and Vascular Homeostasis

 

Catalog No.	Name	Grade and Purity	Suitable Research Direction/Application
A1440682	Activated protein C		APC pathway studies; validation of factor Va/VIIIa inactivation and coagulation braking mechanisms
EJ1514148	Human Antithrombin Ⅲ(AT-Ⅲ) ELISA Kit	BioReagent	Detection of AT-III; evaluation of endogenous anticoagulant capacity
EJ1513948	Human Thrombomodulin/ Soluble (sTM) ELISA Kit	BioReagent	Detection of sTM; evaluation of endothelial injury and anticoagulant platform status
EJ1514849	Human Thrombomodulin (TM) ELISA Kit	BioReagent	Detection of TM; studies on the thrombin-TM-APC axis
H1509976	Human THBD ELISA Kit	BioReagent	Detection of THBD/TM; studies on endothelial homeostasis and anticoagulant surface function
EJ1512306	Rat Thrombomodulin (TM) ELISA Kit	BioReagent	Detection of rat TM; studies on endothelial anticoagulant status in animal models
EJ1513199	Mouse Thrombomodulin (TM) ELISA Kit	BioReagent	Detection of mouse TM; studies on vascular homeostasis and microcirculatory regulation

 

The role of proteases in hemostasis, fibrinolysis, and vascular homeostasis is not a set of isolated single-enzyme reactions, but a continuous proteolytic network jointly constituted by zymogen activation, substrate cleavage, inhibitory feedback, spatial confinement, and vascular wall regulation. Research on this system must simultaneously address coagulation amplification, fibrinolytic restriction, endothelial regulation, and microcirculatory homeostasis in order to accurately understand the molecular basis of bleeding, thrombosis, and vascular-related pathological states.

 

For more related articles, please see below:

[1] Activated partial thromboplastin time (APTT) measurement assay

[2] Structural–Functional Characteristics, Production Technologies, and Application Progress of Thrombin