[Release of plasminogen activator by SIN-1]

Area of Science:

• Pharmacology
• Biochemistry
• Physiology

Background:

• Molsidomine is a vasodilator.
• SIN-1 is a pharmacologically active metabolite of molsidomine.
• Plasminogen activators play a key role in fibrinolysis.

Purpose of the Study:

• To investigate the effect of SIN-1 on plasminogen activator release.
• To characterize the type of plasminogen activator released.
• To determine the dose-response and repeated exposure effects of SIN-1 on activator release.

Main Methods:

• Perfusion of isolated pig ears with SIN-1.
• Measurement of plasminogen activator release.
• Varying SIN-1 concentrations and performing repeated perfusions.

Main Results:

• SIN-1 (10(-7) mol/l) increased plasminogen activator release by approximately 50%.
• Increasing SIN-1 concentration beyond 10(-7) mol/l did not yield further increases.
• The released activator was identified as tissue-type plasminogen activator (t-PA).
• Repeated SIN-1 perfusion did not result in significant additional activator release.

Conclusions:

• SIN-1 effectively stimulates the release of tissue-type plasminogen activator.
• The release mechanism appears to saturate at a specific SIN-1 concentration.
• Repeated stimulation with SIN-1 does not lead to cumulative increases in activator release.