For the experiments with drug infusion (Figures 2–6), catheters (#RPT080 Braintree, MA) were implanted in the femoral artery and vein, tunneled subcutaneously, and exteriorized at the back of the neck in a lightweight tethering spring (Moreno et al., 2007; Pavlov et al., 2013). Following recovery from anesthesia, all rats were placed into individual stainless steel cages that permit daily measurement of arterial blood pressure. The catheters were connected to pressure transducer (#041516504A, Argon Medical Devices, Plano, TX) via swivels (#375/D/22 Instech, Plymouth Meeting, PA) for arterial blood pressure acquisition and intravenous drug infusion with the syringe pump (10 ml/day). The rats were allowed to recover for at least 3 days following surgery.