Chronic catheterization is illustrated using vascular-access-port model SLA where the port is surgically placed subcutaneously on
the back of the rat. The catheter is tunnelled to the neck and inserted into the jugular vein . Within 24 h rats showed normal blood
pressure and blood samples were collected at intervals with minimal stress to the animals . A comparison of the plasma catecholamine
of blood collected from vascular-access-ports with that obtained from decapitation indicates that there was minimal stress to the rats
when blood was drawn through the vascular-access-port