Metyrapone decreases locomotion acutely

Metyrapone blunts stress-induced hyperthermia and increased locomotor activity independently of glucocorticoids and neurosteroids

“…Metyrapone also depressed locomotion acutely in agreement with other studies (Halmy et al, 1970;Canini et al, 2009). Metyrapone may have acted at a peripheral level as (i) its effect on locomotion was concomitant to hypothermia and (ii) the decrease in locomotion occurred without any modification in the u frequency band, which is closely related to locomotion speed (Whishaw and Vanderwolf, 1971;Oddie and Bland, 1998;Slawinska and Kasicki, 1998).…”

Behavioral effects of glucocorticoids during the first exposures to the forced swim stress

“…In the pretest, rats treated with MET showed a marked decrease in immobility in comparison with VEH-treated animals (p<0.05). This decrease in immobility, i.e., an increase in the activity during the forced swimming, was not secondary to the drug effect on motor activity per se because, as was shown previously in the open field test (Canini et al 2009), MET at a dose used inhibits rather than activates animal's locomotion. The decreasing effect of MET on immobility persisted 1 day later, in test session, but the magnitude of the behavioral change became smaller and was only at trend level (p = 0.084).…”

“…In the present study, we blocked the increase in the FS stress-induced corticosterone levels by metyrapone (MET), a glucocorticoid synthesis inhibitor, at a dose that did not affect the basal hormone concentrations (Báez and Volosin 1994;Canini et al 2009;Drouet et al 2010;Roozendaal et al 1996). Instead of corticosterone that binds to both MRs and GRs, dexamethasone (DEX), a synthetic glucocorticoid acted predominantly through GRs (Reul et al 1987(Reul et al , 1989, was used to mimic the acute stress-induced glucocorticoid signal.…”

Behaviour of tail-docked lambs tested in isolation

“…We were not able to clearly determine whether ECs were attempts to establish social contact with flock mates, or whether they were related to exploration of the environment. However, distinguishing vertical from horizontal movements of isolated individuals has been previously reported to provide important information regarding their state (Canini et al, 2009). Therefore, further attention should be paid to EC frequency as it was the only indicator that we found to be affected by the treatments over time.…”