Thromb Haemost 1991; 66(05): 581-585
DOI: 10.1055/s-0038-1646463
Original Article
Schattauer GmbH Stuttgart

Plasminogen Activators t-PA, u-PA and Its Inhibitor (PAI) in Normal Males and Females

Stephen C L Koh
National University of Singapore, Department of Obstetrics and Gynaecology, National University Hospital, Singapore
,
R Yuen
National University of Singapore, Department of Obstetrics and Gynaecology, National University Hospital, Singapore
,
O A C Viegas
National University of Singapore, Department of Obstetrics and Gynaecology, National University Hospital, Singapore
,
S E Chua
National University of Singapore, Department of Obstetrics and Gynaecology, National University Hospital, Singapore
,
B L Ng
National University of Singapore, Department of Obstetrics and Gynaecology, National University Hospital, Singapore
,
D K Sen
National University of Singapore, Department of Obstetrics and Gynaecology, National University Hospital, Singapore
,
S S Ratnam
National University of Singapore, Department of Obstetrics and Gynaecology, National University Hospital, Singapore
› Author Affiliations
Further Information

Publication History

Received 08 March 1990

Accepted 07 May 1991

Publication Date:
25 July 2018 (online)

Summary

We determined the plasma levels of tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI) activity and their antigen levels including urokinase plasminogen activator (u-PA) in 33 male and 27 female normal subjects. Males had mean t-PA activity of 0.50 iu/ml which was significantly lower (p <0.01) than the females 0.64 iu/ml. Males had higher (p <0.001) mean PAI activity (15.5 AU/ml) as compared to females 10.3 AU/ml. The respective mean levels of t-PA and PAI antigen were significantly higher (p <0.01) in males (8.1 ng/ml and 17.6 ng/ml) than in females (6.2 ng/ml and 12.1 ng/ml). The mean u-PA level in males was 1.54 ng/ml which was significantly higher (p <0.01) than in females with 1.02 ng/ml. In post-venous occlusion studies, females had a greater mean response of 8.6 fold in t-PA activity as compared to males with a mean of 4.5 fold increase. The mean t-PA antigen response in males was 2.0 fold increase as compared to 2.6 fold increase in the females. No significant responses were seen in both sexes in either PAI activity or antigen levels when compared with the resting state. In zymography studies, free t-PA, its inhibitor complexes and u-PA were demonstrated in the euglobulin fractions of stored plasma. This study demonstrates that significant differences in t-PA, u-PA and PAI exist between male and female subjects which should be taken into account when determining their levels in clinical conditions.