Emerging evidence demonstrates that thrombin exerts physiological and pathological functions in the central nervous system. Both prothrombin and its active form thrombin have been detected locally in the brain. The cellular functions of thrombin are mainly regulated by G protein-coupled protease-activated receptors (PARs). Thrombin can signal via PAR-1, PAR-3 and PAR-4. Some neurological diseas...

Abstract Secreted modular calcium-binding protein 1 (SMOC1) is an osteonectin/SPARC-related matricellular protein, whose expression regulated by microRNA-223 (miR-223). Given that platelets are rich in miR-223, this study investigated the of SMOC1 and its contribution to platelet function. Human murine expressed SMOC1, whereas from SMOC1+/? mice did not present detectable mature protein. Platel...

We have developed a radioimmunoassay for human thrombin using rabbit anti-human thrombin IgG. The assay can measure 2 ng thrombin/ml plasma, 500-fold more sensitive than clotting assays. Human prothrombin is less reactive in the assay than thrombin by at least four orders of magnitude, and there is no demonstrable cross-reactivity with human factor Xa, the clotting factor structurally most simi...

BACKGROUND Polyphosphate (a linear polymer of inorganic phosphate) is secreted from platelet dense granules, and we recently showed that it accelerates factor V activation by thrombin. OBJECTIVE To examine the interaction of polyphosphate with thrombin. METHODS AND RESULTS Thrombin, but not prothrombin, altered the electrophoretic migration of polyphosphate in gel mobility assays. Thrombin ...

Intracerebral hemorrhage (ICH) is the most serious type of stroke. High level thrombin found in ICH. Ubiquitin-specific protease (USP) 31, a member deubiquitinating enzymes family, has been to negatively regulate NF-κB pathway. However, function USP31 ICH remains largely unknown. In present study, mRNA and protein expression levels were measured by real-time PCR western blot. Flow cytometry was...

The endothelial cell surface membrane protein thrombomodulin binds thrombin with high affinity and acts as both a cofactor for protein C activation and an inhibitor of fibrinogen hydrolysis. We have previously shown that bovine thrombomodulin is a competitive inhibitor of fibrinogen binding to thrombin but has no effect on thrombin activity toward tripeptide substrates or antithrombin III. Henc...

Esterolytically inactive diisopropyl fluorophosphate-conjugated thrombin (DIP-alpha-thrombin) stimulated 3H-thymidine incorporation and proliferation of growth-arrested vascular smooth muscle cells (SMCs), similar to native alpha-thrombin. Half-maximal mitogenic response of SMCs was obtained at 1 nM thrombin and was specifically blocked by the leech-derived, high-affinity thrombin inhibitor, hi...