I have rats that received a 30 minute infusion of control (saline) followed by 30 minutes of a low, mid, and high dose (total 120 minutes). A measurement (heart rate) was taken once during each dose level and control for a total of 4 timepoints. One group of 8 rats received this regiment under one type of anesthesia and another group of twelve received the regiment after a different anesthetic. I want to take means and compare the anesthetics at each matched time point as well as compare each timepoint against the control timepoint for that particular anesthetic. What tests should I run?