1. Thrombin functions as an inflammatory mediator through activation of its receptor
- Author
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S R Stone, Mariarosaria Bucci, Carla Cicala, Giuseppe Cirino, Ludovico Sorrentino, J M Maraganore, Cirino, Giuseppe, Cicala, Carla, Bucci, Mariarosaria, Maraganore, Jm, Sorrentino, Ludovico, Stone, Sr, L., Sorrentino, J. M., Maraganore, and S. R., Stone
- Subjects
Male ,metabolism, Inflammation ,drug effects/ultrastructure, Edema, Hirudin ,pharmacology, Serotonin ,Carrageenan ,chemistry.chemical_compound ,Edema ,Immunology and Allergy ,Mast Cells ,Degranulation ,Thrombin ,Articles ,Hirudins ,Mast cell ,pharmacology, Rats, Rat ,Extravasation ,Recombinant Proteins ,medicine.anatomical_structure ,Wistar, Receptor ,analogs /&/ derivatives/pharmacology, Histamine ,medicine.symptom ,Histamine ,medicine.drug ,medicine.medical_specialty ,Serotonin ,Amino Acid Sequence, Animals, Antithrombin ,Immunology ,Molecular Sequence Data ,physiopathology, Male, Mast Cell ,Cytoplasmic Granules ,Antithrombins ,Internal medicine ,Thrombin receptor ,medicine ,Animals ,Amino Acid Sequence ,Cimetidine ,Rats, Wistar ,Inflammation ,pharmacology, Carrageenan, Cytoplasmic Granule ,metabolism, Thrombin ,Peptide Fragments ,Rats ,Endocrinology ,chemistry ,drug effects/pathology/physiology, Molecular Sequence Data, Peptide Fragment ,drug effects/physiology, Recombinant Protein ,Receptors, Thrombin ,pharmacology - Abstract
A rat model of inflammation was used to investigate the biological effects of thrombin. The thrombin-specific inhibitor Hirulog markedly attentuated the carrageenin-induced edema of the paw of the rat. Injection of thrombin into the paw also produced edema. The effect of thrombin was due to activation of its receptor; a thrombin receptor activating peptide (TRAP) reproduced the effects of thrombin in causing edema. TRAP also increased vascular permeability as demonstrated by extravasation of Evans blue and 125I-labeled serum albumin. The release of bioactive amines played an important role in mediating the TRAP-induced edema; the serotonin/histamine antagonist cryproheptadine and the histamine H2 receptor antagonist cimetidine reduced significantly the edema caused by TRAP. Treatment of rats with the mast cell degranulator 48/80 to deplete these cells of their stores of histamine and serotonin abolished completely the ability of TRAP to produce edema. Histochemical examination confirmed that TRAP treatment led to mast cell degranulation. Thus, it has been possible to demonstrate that thrombin acts as an inflammatory mediator in vivo by activating its receptor, which in turn leads to release of vasoactive amines from mast cells.
- Published
- 1996