Fig. 2.

A single, prophylactic injection of RS-67,333 attenuates learned fear and prevents novelty-induced hypophagia in male 129S6/SvEv mice. a Experimental design. b Mice administered 30 mg/kg, but not 1.5 or 10 mg/kg, of RS-67,333 exhibited significantly less freezing during CFC training when compared with mice administered saline. c, d Mice administered 1.5 or 10 mg/kg, but not 30 mg/kg, of RS-67,333 at exhibited significantly less freezing when compared with mice administered saline. e Mice administered 10 mg/kg, but not 1.5 or 30 mg/kg, of RS-67,333 exhibited reduced immobility when compared with mice administered saline during day 1 of the FST. f, g All groups of mice had comparable amounts of immobility during day 2 of the FST. h, i RS-67,333 (10 mg/kg) did not alter distance traveled or time spent in the center of the OF when compared to saline mice. j, k Both groups of mice had comparable time spent in the open arms and entries into the open arms of the EPM. l, m Mice administered RS-67,333 (10 mg/kg) exhibited a significantly reduced latency to feed when compared with saline mice. n Mice in both groups ate a comparable amount of food in the home cage following the NSF. o Following food deprivation, mice in both groups lost a comparable amount of weight. (n = 5–29 male mice per group). Error bars represent ± SEM. *p < 0.05; ***p < 0.001. Sal saline, CFC contextual fear conditioning, FST forced swim test, OF open field, EPM elevated plus maze, NSF novelty suppressed feeding, min minutes, sec seconds, g grams, mg milligram, kg kilogram, no. number, cm centimeter