Plasminogen activator inhibitor 1, the primary regulator of fibrinolysis, in normal human cerebrospinal fluid.
The occurrence of type-1 plasminogen activator inhibitor (PAI-1) in human cerebrospinal fluid (CSF) has not previously been reported. As a member of the serpin superfamily of serine protease inhibitors and an acute phase response component, PAI-1 has powerful potential roles in nervous system homeostasis. We have detected this serpin antigen using a polyclonal anti-PAI-1 antibody in normal human CSF. In Western blotting, PAI-1 in several CSF samples appears as a two-band antigen of Mr = 54 and 35 kDa, presumably the intact and proteolytic fragment, respectively. In vitro complex formation studies confirm that the 54 kDa form of PAI-1 interacts with 125I-urokinase after activation with SDS, but the 35 kDa form does not. Quantification of total PAI-1 antigen in 18 normal human CSF samples by ELISA reveals a mean value of 1.0 +/- 0.07 (SEM) micrograms/dL, indicating that a relatively low concentration of the inhibitor occurs in normal human CSF. This information should now allow comparison of PAI-1 levels and activity in various neurologic disorders.
Rao
J S
JS
Neurobiology Research Laboratory, Department of Veterans Affairs Medical Center, Kansas City, Missouri 64128.
Chen
M
M
Festoff
B W
BW
D000544:Alzheimer Disease / Q000134:cerebrospinal fluid; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D005342:Fibrinolysis / Q000502:physiology*; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D017395:Plasminogen Activator Inhibitor 1 / Q000134:cerebrospinal fluid* / Q000276:immunology; D014568:Urokinase-Type Plasminogen Activator / Q000302:isolation & purification
D007457:Iodine Radioisotopes; D017395:Plasminogen Activator Inhibitor 1; D014568:Urokinase-Type Plasminogen Activator