Stability of daily food selection.

<p>Stability of daily (24 hr) food selection in rats (n = 18) offered an <i>ad libitum</i> free choice diet of normal chow, 1 g sucrose pellets and lard (a saturated animal fat). Data are shown for the last 4 baseline days (day 11–14) prior to ICV injection, and for the injection days in which 2 μg ghrelin or aCSF were administered. The data are expressed as mean ± SEM kcal consumed as % of daily total kcal intake.</p

Impact of intra-VTA ghrelin on dietary choice.

<p>Impact of acute intra-VTA (ventral tegmental area) injection of ghrelin on total energy intake and dietary choice during (A) 3 hr, (B) 6 hr and (C) 24 hr, in rats (n = 17) that had been <i>ad libitum</i> fed a choice diet comprising normal chow, 1 g sucrose pellets and lard (saturated animal fat) over the previous 14 days. All rats received ghrelin and vehicle solution in a cross over design with one day washout between injections. **P<0.01, ***P<0.001.</p

Impact of fasting and peripherally administered ghrelin receptor antagonist on dietary choice.

<p>Impact of acute intraperitoneal injection of a ghrelin receptor antagonist on fasting-induced changes in total energy intake and dietary choice measured during (A) 3 hr, (B) 6 hr and (C) 24 hr after the end of an overnight fast, in rats (n = 24) that had been <i>ad libitum</i> fed a choice diet comprising normal chow, 1 g sucrose pellets and lard (saturated animal fat) for 14 days prior to fast. All rats received the antagonist and saline solution in a cross over design with one day washout between injections. In panels A and B; **P<0.01. In panel C, the letters indicate significant differences (rANOVA, P<0.01).</p

Impact of ICV ghrelin on dietary choice.

<p>Impact of acute intracerebroventricular (ICV) injection of ghrelin on total energy intake and dietary choice during (A) 3 hr, (B) 6 hr and (C) 24 hr, in rats (n = 18) that had been <i>ad libitum</i> fed a choice diet comprising normal chow, 1 g sucrose pellets and lard (saturated animal fat) over the previous 14 days. All rats received ghrelin and vehicle solution in a cross over design with one day washout between injections. *P<0.05, **P<0.01, ***P<0.001.</p

Impact of ghrelin receptor knockout on dietary choice.

<p>Total energy intake and dietary choice were measured during (A) 3 hr, (B) 6 hr and (C) 24 hr after the end of an overnight fast, in ghrelin receptor knockout mice (GHSR-KO) and wild-type (WT) controls that had been <i>ad libitum</i> fed a choice diet comprising normal chow, 1 g sucrose pellets and lard (saturated animal fat) for 14 days prior to the overnight fast. **P<0.01 (one-way ANOVA).</p

Time spent in the different zones of the open-field during the re-exposure to the context.

<p>Starting 8 days after exposure to stress, control (CTR), cat fur odor (ODOR), immobilization (IMO) and cat fur odor+immobilization (ODOR+IMO) rats were re-exposed to the stress-paired context. Then, permanence time (%), divided by time blocks (5 min each), was measured on day 9 in (A) the zone where the cloth was placed (Z1), (B) the intermediate zone (Z2), and (C) the zone opposite to the cloth (Z3). The same parameters were again measured on day 10 (panels D–F). ⁺ p<0.05 versus non-IMO animals; * p<0.05, ** p<0.01, *** p<0.001 versus non-odor exposed animals.</p

Long-term effects of stress in the elevated plus-maze (EPM).

<p>Animals were exposed for 15 min to the EPM 7 days after initial exposure to the different stressors: none (CTR), cat fur odor (ODOR), immobilization (IMO) or cat fur odor+immobilization (ODOR+IMO). (A) Percent of time spent in the open arm, (B) Open arm entries, (C) Closed arm entries. * p<0.05, ** p<0.01 versus non-odor exposed animals.</p

Distance travelled during the re-exposure to the context.

<p>Starting 8 days after exposure to stress, control (CTR), cat fur odor (ODOR), immobilization (IMO) and cat fur odor+immobilization (ODOR+IMO) rats were re-exposed to the stress-paired context. Panel A shows the distance traveled during the first context re-exposure on day 9, divided by time blocks (5 min each) and Panel B the same parameter during the second context re-exposure on day 10. * p<0.05; *** p<0.001 versus non-odor exposed animals.</p

Acute behavioral response to cat odor.

<p>Behavioral measures recorded on day 1 during the 20 min exposure to an open field containing a clean cloth (CTR) or a cloth impregnated with cat fur odor (ODOR), expressed by time blocks (5 min each). It's shown the (A) Distance traveled (cm) in the whole of the open field, (B) Permanence time (%) in the zone where the cloth was placed (Z1), (C) Permanence time in the intermediate zone (Z2), and (D) Permanence time in the opposite zone to the cloth (Z3). *** p<0.001 versus non-odor exposed animals.</p

Endocrine response to the elevated plus-maze (EPM).

<p>Animals were exposed for 15 min to the EPM 7 days after initial exposure to the different stressors: none (CTR), cat fur odor (ODOR), immobilization (IMO) or cat fur odor+immobilization (ODOR+IMO). Plasma ACTH and Corticosterone responses to the EPM were measured. Basal levels taken after the handling period were 20±1 pg/ml for ACTH and 0.9±0.2 µg/dl for corticosterone. No significant differences between groups were found.</p