Figure 2. Time course of ACh in pmol/10 min of LDT dialysis during a representative experiment from one animal. LDT ACh is plotted as a function of dialysis time in min. Time bins 10-50 plot ACh during Ringer's solution (control) dialysis. Time bins 60-100 indicate ACh during dialysis delivery of morphine to the LDT, and bins 110-150 show dialysis delivery of naloxone (88 nM). There are no indications of variance here because each bar represents the pmol value of ACh measured during one 10-min dialysis sample. In contrast, the data summarized by Figure 3, Figure 4, Figure 5, Figure 6, Figure 7represent mean change in ACh release averaged by condition for multiple experiments conducted in multiple animals.