Amplifier ml 785

Blood pressure was monitored using a cannula placed in the femoral artery as previously described^{29 (link)}. Briefly, a heparinized polyethylene cannula was inserted 3 cm proximally into the left femoral artery and secured to the surrounding tissue. The line was connected to a pressure transducer (Transpac, Abbott Critical Care Systems, Sligo, Ireland), whose signal (Bridge Amp ML 110, Amplifier ML 785, Powerlab/8SP, ADInstruments, Colorado Springs, CO, USA) gave direct and continuous BP monitoring (Lab Chart 7, ADInstruments).

ICP was manipulated via a custom made dual-cannula placed into the lateral ventricle on the side ipsilateral to the cannulated eye^{13 (link)}. The dual-lumen cannula consisted of a 23 G outer needle (0.6 mm diameter × 19 mm length, Becton Dickinson, Franklin, WI, USA) and a 30 G (0.3 mm diameter × 13 mm length, Becton Dickinson) inner needle, which were connect via polyethylene tubing (0.8 mm) to a pressure transducer (Transpac, Abbott Critical Care System) and a syringe pump (Pump 11 Elite Syringe Pumps, Harvard Apparatus, Holliston, MA, USA), respectively. This allowed for simultaneous ICP manipulation (Bridge Amp ML 110, Amplifier ML 785, Powerlab/8SP, ADInstruments) and recording (Lab Chart 7, ADInstruments). To prepare for lateral ventricle cannulation, rats were anesthetized and placed on a stereotaxic platform (Model 900, David Kopf Instruments, Los Angeles, CA, USA). A 2 cm by 2 cm flap of skin above the skull was removed. Connective tissue around the calvarial area was removed to expose the coronal sutures. Using a dental burr attached to a drill (Model 300, Dremel®, Robert Bosch Tool Corporation, Racine, WI, USA), a hole was drilled through the skull at 1.5 mm caudal to bregma and 2 mm lateral to the midline. The cannula was then inserted to a depth of 3.5 mm³⁰ .