Data are average rates of feeding (g/min) ±SEM in rats fed tannic acid (TA), sucrose octaacetate (SOA), or control diet. (A-D) Closed bars represent the 3-day average of rate of feeding for control animals during the pre-treatment phase, during which they consumed control diet, while open bars represent experimental animals who were exposed to either TA (A), IPR injections (B, C), or SOA (D). Closed circles represent quinine intake of control animals, while open circles represent quinine intake of pretreated animals. TA (A) and IPR pre-treated (C, D) animals ate quinine faster than their controls.