Extravasation of proteins in the joint tissue: differential behaviour of native BSA and cationic mBSA.

Mice were intravenously injected with 125I-labelled native BSA and cationic mBSA. The amount of 125I-protein in the extra- and intravascular compartment was determined in normal joints and in joints in which the vascular permeability was increased by histamine. The extravasation of BSA and mBSA is different. More BSA compared with mBSA accumulated in normal joints and the extravasation of BSA increased almost 3 times shortly after histamine injection, whereas histamine hardly affected the extravasation of mBSA.