Influence of anabolic steroid on anxiety levels in sedentary male rats

Abstract

The aim of this study was to evaluate the influence of nandrolone decanoate on anxiety levels in rats. Male Wistar rats were treated with nandrolone decanoate (5mg/kg, two times per week, i.m.) or vehicle (propylene glycol--0.2 ml/kg, two times per week, IM) for 6 weeks. Control rats were subject only to procedures related to their routine husbandry. By the end of 6 weeks, all groups (24-29 rats/group) were submitted to the elevated plus maze test in order to evaluate their anxiety level. Some of these animals (12-14/group) were treated with diazepam (1 mg/kg i.p.) 30 min before the elevated plus maze test. Nandrolone decanoate significantly decreased the percentage of time spent in the open arms (1.46+/-0.49%) compared with control (3.80+/-0.97%) and vehicle (3.96+/-0.85%) groups, with no difference between control and vehicle treatments. The percentage of open arm entries was also reduced in the group treated with nandrolone decanoate in comparison with the vehicle and control. No changes in the number of closed arm entries were detected. Diazepam abolished the effects of nandrolone decanoate on the percentage of time in, and entries into the open arms. The present study showed that chronic treatment with a high dose of nandrolone decanoate increased the anxiety level in male rats.

Acute 19-nortestosterone transiently suppresses hippocampal MAPK pathway and the phosphorylation of the NMDA receptor

“…A reduction of the phosphorylation state in the hippocampus is shown to impair the retrieval of contextual fear memory in mice [17,18]. Androgens are reported to affect mood and while long-term treatment with AAS is anxiogenic in rats [41,42], testosterone has been shown to rapidly (after 30 min) decrease anxiety in mice [16]. Moreover, male rats with recent sexual experience show increased hippocampal testosterone and decreased anxiety-like behaviour [43].…”

Metabolic and behavioral effects of ractopamine at continuous low levels in rats under stress

“…The longer the animal stay in open arms and the larger the number of entries in these arms, their anxiety would be lower (Cruz et al 1994). On the other hand, the larger the number of entries in both the arms (open and closed), the greater would be their locomotor activity (Cruz et al 1994;Rocha et al 2007). The EPMT of this study pointed to the changes in rat response due to an interaction between the RAC and stress, as increased entries and time spent in open arms.…”

“…The results were converted to: 1) Percentage of opened arm exploration time (%OAT); 2) Percentage of entries on opened arms (%EOA); 3) Number of entries on closed arms (ECA) (Cruz et al, 1994). Other two parameters were also assessed: number of times final edge of opened arms and number of times the animal walked towards the center of the maze, but did not enter another arm (Cruz et al 1994;Rocha et al 2007). …”

“…Each animal was submitted only once to this test, being put in the center of the maze facing one of the closed arms. Their behavior was recorded for five min, and the film was viewed and assessed by three trained investigators who did not know, which treatment the animal was subjected, (i.e., blind experiment) (Rocha et al 2007). The results were converted to: 1) Percentage of opened arm exploration time (%OAT); 2) Percentage of entries on opened arms (%EOA); 3) Number of entries on closed arms (ECA) (Cruz et al, 1994).…”

“…They were submitted to the last stress session, and immediately after restraining, they were taken to the elevated plus-maze (EPMT). The maze was constructed according to Rocha et al (2007), with wood painted black and consisted of two open arms, positioned opposite of each other, and intersected at a 90° angle by two other arms, which were closed. This behavioral test was done in a room with artificial light (Lamp 100w), and acoustic and thermal insulation.…”