The effects of intra-arterially administered histamine on vascular permeability

Abstract

The influence of intra-arterially administered histamine on the permeability of the articular barrier (synovial membrane plus vascular endothelium) was studied in cats. The dye penetration from the blood through the barrier was tested by perfusing the two knee joints with saline; the histamine solution was infused through one of the circumflex branches of the femoral artery. The dye content of the two perfusates was measured colorimetrically, the local blood supply of the two knee joints thermo-electrically. In the great majority of experiments it was found that the dye excretion was considerably reduced on the histamine-infused side, in spite of marked improvement of blood supply.