Differences in physicochemical properties between tissue plasminogen activators from human paranasal mucous membrane and pig heart.

In order to clarify the physicochemical property of tissue plasminogen activator (TA), tissue extracts of human paranasal mucous membrane and pig heart were studied by the biochemical techniques. The studies by gel filtration revealed that two plasminogen activators of different molecular weight were present in the extract of human paranasal mucous membrane. The existence of tissue plasminogen activator with a low molecular weight (LMW-TA) has not previously been reported. This molecular weight of this compound was lower than that of cytochrome c. On the other hand, the molecular weight of tissue plasminogen activator from pig heart (PH-TA) was similar to that of ovalbumin, about 46,000 daltons, as estimated by Sephadex G-150 gel filtration. From the physicochemical property of LMW-TA, it is suggested that the LMW-TA from paranasal mucous membrane with chronic sinusitis was produced by proteases, i.e. trypsin-like enzyme, present in the mucous membrane with chronic inflammation.