scholarly journals Effect of intrafollicular indomethacin injection on gonadotropin surge-induced expression of select extracellular matrix degrading enzymes and their inhibitors in bovine preovulatory follicles

Reproduction ◽  
2006 ◽  
Vol 131 (3) ◽  
pp. 533-543 ◽  
Author(s):  
Qinglei Li ◽  
Fermin Jimenez-Krassel ◽  
Yasuhiro Kobayashi ◽  
James J Ireland ◽  
George W Smith
Keyword(s):  
Extracellular Matrix ◽  
Plasminogen Activator ◽  
Tissue Plasminogen Activator ◽  
Follicular Fluid ◽  
Tissue Inhibitor Of Metalloproteinase ◽  
Tissue Inhibitor ◽  
Preovulatory Follicles ◽  
Tissue Plasminogen ◽  
Gonadotropin Surge ◽  
Matrix Degrading Enzymes

A growing body of evidence supports an obligatory role for intrafollicular prostanoids in the mechanism of ovulation. However, the prostanoid-dependent mediators of the follicular extracellular matrix degradation required for ovulation are unknown. The objectives of this study were to determine the cellular compartment(s) in which the gonadotropin surge-induced regulation of select extracellular matrix degrading enzymes and their cognate inhibitors occurs in bovine preovulatory follicles, and to test whether such regulation is blocked by intrafollicular administration of the prostanoid synthesis and ovulation inhibitor, indomethacin (INDO). Follicular fluid prostaglandin E2concentrations were elevated in diluent-treated follicles before ovulation (24 h after GnRH injection), but the increase was blocked in INDO-treated follicles. Real-time PCR analysis revealed the specific follicular cell types where gonadotropin surge-induced increases in mRNA abundance for members of the matrix metalloproteinase/tissue inhibitor of metalloproteinase and plasminogen activator families occurred. INDO treatment increased thecal cell mRNA for tissue inhibitor of metalloproteinase-4 and its protein abundance in the apex of preovulatory follicles before ovulation, but suppressed granulosal cell mRNA and activity for tissue plasminogen activator in follicular fluid and the follicle apex. Plasmin activity was also suppressed in the follicular fluid of INDO-treated follicles. Effects of INDO injection on select matrix metalloproteinases were not observed. The results suggest that gonadotropin surge-induced regulation of tissue inhibitor of metalloproteinase-4 and tissue plasminogen activator may be prostanoid dependent, and support a potential role for increased tissue plasminogen activator expression and decreased tissue inhibitor of metalloproteinase-4 expression in the mechanism of ovulation.

Tissue plasminogen activator as a modulator of neuronal survival and function

2002 ◽  
Vol 30 (2) ◽  
pp. 222-225 ◽  
Author(s):  
S. E. Tsirka
Keyword(s):  
Central Nervous System ◽  
Extracellular Matrix ◽  
Nervous System ◽  
Neurite Outgrowth ◽  
Plasminogen Activator ◽  
Tissue Plasminogen Activator ◽  
Cell Surface Receptor ◽  
Mammalian Brain ◽  
Tissue Plasminogen ◽  
Surface Receptor

The tissue plasminogen activator (tPA)/plasmin proteolytic system has been implicated in both physiological and pathological processes in the mammalian brain. The physiological roles include facilitating neurite outgrowth and pathfinding. The pathological role involves mediating a critical step in the progression of excitotoxin-induced neurodegeneration. Mechanistically, tPA appears to function through two pathways. The first pathway proceeds via its well established ability to convert plasminogen into plasmin. Plasmin then either promotes neuronal death via both the degradation of the extracellular matrix and the establishment of chemoattractant gradients for microglia, or facilitates neurite outgrowth through the processing of extracellular matrix proteoglycans. The second pathway for tPA does not involve its proteolytic activity: rather tPA functions as an agonist to stimulate a cell-surface receptor on microglia (the macrophage-like immunocompetent cells of the central nervous system) and results in their activation. Once activated after neuronal injury, microglia contribute to the ensuing neurodegeneration. Using tPA as a link between neurons and microglia, we are focusing on understanding their communication and interactions in the normal and diseased central nervous system.

Tissue plasminogen activator as a novel diagnostic aid in acute pulmonary embolism

VASA ◽  
2014 ◽  
Vol 43 (6) ◽  
pp. 450-458 ◽  
Author(s):  
Julio Flores ◽  
Ángel García-Avello ◽  
Esther Alonso ◽  
Antonio Ruíz ◽  
Olga Navarrete ◽  
...  
Keyword(s):  
Pulmonary Embolism ◽  
Negative Predictive Value ◽  
Plasminogen Activator ◽  
Tissue Plasminogen Activator ◽  
Predictive Value ◽  
Acute Pulmonary Embolism ◽  
Enzyme Linked Immunosorbent Assay ◽  
Diagnostic Utility ◽  
Tissue Plasminogen ◽  
D Dimer

Background: We evaluated the diagnostic efficacy of tissue plasminogen activator (tPA), using an enzyme-linked immunosorbent assay (ELISA) and compared it with an ELISA D-dimer (VIDAS D-dimer) in acute pulmonary embolism (PE). Patients and methods: We studied 127 consecutive outpatients with clinically suspected PE. The diagnosis of PE was based on a clinical probability pretest for PE and a strict protocol of imaging studies. A plasma sample to measure the levels of tPA and D-dimer was obtained at enrollment. Diagnostic accuracy for tPA and D-dimer was determined by the area under the receiver operating characteristic (ROC) curve. Sensitivity, specificity, predictive values, and the diagnostic utility of tPA with a cutoff of 8.5 ng/mL and D-dimer with a cutoff of 500 ng/mL, were calculated for PE diagnosis. Results: PE was confirmed in 41 patients (32 %). Areas under ROC curves were 0.86 for D-dimer and 0.71 for tPA. The sensitivity/negative predictive value for D-dimer using a cutoff of 500 ng/mL, and tPA using a cutoff of 8.5 ng/mL, were 95 % (95 % CI, 88–100 %)/95 % (95 % CI, 88–100 %) and 95 % (95 % CI, 88–100 %)/94 %), respectively. The diagnostic utility to exclude PE was 28.3 % (95 % CI, 21–37 %) for D-dimer and 24.4 % (95 % CI, 17–33 %) for tPA. Conclusions: The tPA with a cutoff of 8.5 ng/mL has a high sensitivity and negative predictive value for exclusion of PE, similar to those observed for the VIDAS D-dimer with a cutoff of 500 ng/mL, although the diagnostic utility was slightly higher for the D-dimer.

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