Animals were anesthetized prior to catheter implantation, using the same anesthetic cocktail used for cannulation surgery. Catheters were hand-made according to Hansen et al. (2007) and to the method described in detail by Caine et al. (1993), using the specifications for the catheter tubes as described below. CBAS ® heparin-coated PU catheters 3.5FR (Instech laboratories INC, Plymouth Meeting, PA) were used to prolong the life of catheters. Briefly, these tubes were fitted on an L-shaped external guide cannula (Plastics One Inc.; Roanoke, VA), that was then anchored with dental acrylic to a circular piece of propylene mesh (diameter ∼1cm) to form a pedestal. To implant the catheter, the pedestal end of the catheter was threaded subcutaneously between the scapulae, while the open end of the tube was threaded 27 mm into either the left or right jugular vein. Post surgery, the catheters were flushed daily with saline 0.4 cc, 0.2 cc saline containing heparin (70 u/cm3), and 0.1 cc of antibiotic ticarcillin (Timentin®, 100 mg/ cm3; GlaxoSmithKline, Research Triangle Park, NC). The implanted catheters were monitored daily for patency and
