Related Experiment Video
Updated: Jul 29, 2026
10:37
Ferric Chloride-induced Murine Thrombosis Models
Published on: September 5, 2016
Coronary thrombolysis with recombinant human tissue-type plasminogen activator
Circulation
|October 1, 1984
Summary
Recombinant tissue-type plasminogen activator (rt-PA) effectively dissolves coronary clots in dogs, with higher doses leading to faster reperfusion and significantly reduced heart damage. This study highlights rt-PA
Area of Science:
- Cardiovascular Research
- Pharmacology
- Thrombosis and Hemostasis
Background:
- Coronary thrombosis is a major cause of myocardial infarction.
- Effective thrombolytic therapy is crucial for salvaging heart tissue.
- Recombinant tissue-type plasminogen activator (rt-PA) is a potential therapeutic agent.
Purpose of the Study:
- To evaluate the thrombolytic potency of intravenous rt-PA in a canine model of coronary thrombosis.
- To assess the infarct-sparing potential of rt-PA following coronary reperfusion.
- To determine the dose-dependent effects of rt-PA on thrombolysis and myocardial salvage.
Main Methods:
- Localized coronary thrombosis was induced in anesthetized dogs.
- Intravenous infusion of rt-PA at varying doses was administered after 2 hours of occlusion.
- Reperfusion time, ST-segment elevation, and infarct size (triphenyl tetrazolium chloride staining) were measured.
- A randomized, blinded study compared rt-PA to saline treatment.
Main Results:
- rt-PA achieved dose-dependent coronary reperfusion, with lysis times decreasing at higher infusion rates.
- Higher rt-PA doses resulted in rapid thrombolysis (e.g., 13 +/- 3 min at 25 micrograms/kg/min).
- rt-PA treatment significantly reduced myocardial infarct size (2.5% vs. 16% in controls, p = .001) without systemic fibrinolytic activation or significant blood pressure changes.
Conclusions:
- Intravenous rt-PA facilitates rapid and dose-dependent coronary thrombolysis.
- Early reperfusion with rt-PA is associated with substantial myocardial salvage.
- rt-PA demonstrates significant infarct-sparing potential without systemic adverse effects on hemostasis.
Related Concept Videos
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
01:16Vascular Spasm
The vascular phase, also known as vasospasm, is the initial stage of hemostasis, crucial for preventing excessive bleeding when a blood vessel is injured. After a vessel is cut, nerves in the damaged area trigger pain and other sensory impulses. Simultaneously, the smooth muscles in the vessel wall contract, resulting in a vascular spasm. This contraction reduces the vessel's diameter at the injury site, slowing or stopping blood loss through the vessel wall. Vascular spasms typically last for...
01:22Formation of the Platelet Plug
The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
01:16Clot Retraction and Fibrinolysis
After a fibrin clot is formed, the next step is clot retraction, a vital process facilitated by platelet contractile proteins, such as actin and myosin. These proteins pull the fibrin strands closer together and condense the clot. This action reduces the size of the clot, creating a smaller, denser structure that effectively seals off the damaged vessel. Clot retraction consolidates the clot and helps with wound healing by bringing the edges of the damaged blood vessel closer together.
01:27Peripheral Artery Disease III: Interprofessional Care
Peripheral Artery Disease (PAD) is characterized by narrowed arteries that diminish blood flow to the extremities. Effective management of PAD requires an interprofessional approach involving various healthcare professionals. The critical aspects of interprofessional care for PAD patients focus on risk factor modification, drug therapy, exercise therapy, nutrition therapy, critical limb ischemia care, and interventional radiology and surgical procedures.The primary treatment goal for PAD...
01:29Venous Thrombosis III: Interprofessional Care
Venous thrombosis requires effective prevention and treatment strategies to improve patient outcomes and reduce potential complications.Prevention StrategiesHealthcare providers must prioritize preventing venous thromboembolism (VTE) for all adult patients upon admission. Interventions depend on bleeding and thrombosis risk, medical history, current medications, diagnoses, planned procedures, and patient preferences. Patients on bed rest should change positions every two hours and, if not...