Fig. 1. Schematic diagram of apparatus (Disposwivel Kit, Bioresearch Center) used for continuous subcutaneous infusion in hamsters. A swivel needs less torque for rotation than does the current standard type. A coiled spring tube connecting the swivel and an infusion catheter allow hamsters to move freely in a cage. A protective wire tube prevents animals from biting the infusion catheter. Minimum fixation using No. 4 silk sutures is necessary to secure the catheter.