1.   These results give rise to the hypothesis that endothelin might increase the tissue type plasminogen activator activity accompanying the gastric mucosal injury.

2.   Tissue type plasminogen activator activity in plasma was assayed by the specific chromogenic substrate assay, which was a modification of the method described by Rnby et al.

3.   The amount of colour developed during a fixed time is proportional to the tissue type plasminogen activator activity in the sample.

4.   It was clearly shown that tissue type plasminogen activator activity was significantly correlated with the mucosal lesion.

5.   Tumour extracts of different origin such as breast, lung, prostate, stomach, and colon were found to have raised concentrations of plasminogen activator activities.

6.   Moreover, tissue type plasminogen activator antigen as well as tissue type plasminogen activator activity in oesophageal carcinoma tissue were not different from normal tissue concentrations.

7.   In the present study tissue type plasminogen activator activity in columnar carcinomas of the stomach, however, was significantly decreased.

8.   Neither study, however, quantified the overall plasminogen activator activity of malignant ascites.