The sensitive measurement of total rat PAI-1 antigen is easily performed with this 96 well strip format ELISA kit. Rat PAI-1 binds capture antibody coated onto a micro titer plate. Free, latent and complexed rat PAI-1 will bind to the capture antibody. Polyclonal rabbit anti-rat PAI-1 primary antibody binds to the captured PAI-1. Excess antibody is washed away, and bound polyclonal antibody is then reacted with the secondary antibody. TMB substrate is used for color development at 450 nm. All reagents and standards are provided in these ELISA kits.