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Extrinsic and Intrinsic Pathways of Hemostasis

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Related Experiment Video

Updated: May 29, 2026

A Liposome Membrane Permeability Assay for Investigating the Effects of Phosphatidylinositol Phosphate Groups on Membranotropic Action of Venom PLA2

A Liposome Membrane Permeability Assay for Investigating the Effects of Phosphatidylinositol Phosphate Groups on Membranotropic Action of Venom PLA₂

Published on: September 26, 2025

Phospholipase A(2) activates hemostasis.

Thomas W Stief¹

¹Department of Clinical Chemistry, University Hospital Giessen & Marburg, Germany.

Drug Target Insights

|September 9, 2011

Summary

Phospholipases A(2) (PLA(2)) enzymes activate blood coagulation, leading to pathological disseminated intravascular coagulation (PDIC). Early diagnosis by screening patients for plasmatic thrombin activity is crucial for life-threatening conditions.

Keywords:

PDIC PLA2 Phospholipase contact phase intrinsic hemostasis thrombin

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Last Updated: May 29, 2026

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The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well

The Nijmegen Hemostasis Assay: Simultaneous Fluorogenic Measurement of Thrombin and Plasmin Generation in a Single Well

Published on: February 27, 2026

Area of Science:

Biochemistry
Hematology
Enzymology

Background:

Phospholipases A(2) (PLA(2)) are enzymes that degrade cell membrane phospholipids.
PLA(2) activity can initiate the kallikrein-mediated contact phase of coagulation.
Elevated PLA(2) levels are observed in conditions like trauma, pancreatitis, and sepsis.

Purpose of the Study:

To investigate the effect of PLA(2) on thrombin generation in human blood.
To quantify thrombin generation in recalcified plasma after exposure to PLA(2).

Main Methods:

Citrated whole blood was incubated with bovine pancreatic or snake PLA(2), LPS, or zymosan A.
Plasma was recalcified and thrombin generation was measured using a chromogenic assay.
Arginine was used to stop the coagulation reaction and depolymerize fibrin.

Main Results:

PLA(2) induced dose-dependent thrombin generation, comparable to LPS and zymosan A.
Thrombin generation was proportional to PLA(2) concentration up to 60 ng/ml.
High PLA(2) concentrations (10 μg/ml) also induced significant thrombin generation, unlike in control plasma.

Conclusions:

Elevated plasmatic PLA(2) activates the hemostasis system, potentially causing pathological disseminated intravascular coagulation (PDIC).
Screening for plasmatic thrombin activity is recommended for early diagnosis of these critical conditions.