Early deprivation increases high-leaning behavior, a novel anxiety-like behavior, in the open field test in rats

Dong

Intl J of Devlp Neuroscience

et al. 2017

There is little research on the effects of adolescent administration of antidepressants on behavioural function and inflammation in early-life stressed adult mice. Using maternal separation (MS), a paradigm of early adversity, we investigated the effects of adolescent (PND 33-54) escitalopram (ES; 10mg/kg) exposure on depression- and anxiety-like behaviours and the levels of inflammatory cytokines (interleukin [IL]-1β, tumor necrosis factor [TNF]-α, and IL-10) in the ventral hippocampus (HPV), prefrontal cortex (PFC), and serum in adult (PND 61) male offspring mice. The results showed that MS has no effect on locomotor activity, but increased depression-like behaviours in the saccharin preference test and increased anxiety-like behaviours in the social preference and elevated plus maze tests. MS increased the levels of IL-1β in the HPV, PFC, and serum, while decreasing the level of IL-10 in the HPV. Furthermore, adolescent ES treatment inhibited these depression- and anxiety-like behaviours, decreased the levels of IL-1β, and increased the level of IL-10 in the HPV. The results also showed that there are no effects of chronic escitalopram administration on normal behaviour in control mice. Taken together, the current data provide experimental evidence that MS increases depression and anxiety levels in adult male offspring. Additionally, the findings support the idea that early pharmacological intervention with ES may be an effective treatment for reducing the behavioral abnormalities induced by early adversity and regulating the underlying inflammatory mechanisms involved.

Section: Discussionsupporting

confidence: 94%

Adolescent escitalopram prevents the effects of maternal separation on depression‐ and anxiety‐like behaviours and regulates the levels of inflammatory cytokines in adult male mice

Dong

Intl J of Devlp Neuroscience

et al. 2017

“…Rats tend to avoid the center region of the arena in favor of the wall. 15 Rats in each group were allowed to explore the arena for 10 min and movement distance, time spent in the center and wall, movement velocity, and fecal pellets were recorded for anxiety mood evaluation.…”

Section: Open Field Testmentioning

confidence: 99%

<p>Dexmedetomidine Promotes Hippocampal Neurogenesis and Improves Spatial Learning and Memory in Neonatal Rats</p>

Zhang¹,

Gao²,

Wu³

et al. 2020

DDDT

Background: Dexmedetomidine (Dex) is a highly selective α2-adrenoceptor agonist used as an off-label medication for pediatric sedation and analgesia. Recently, Dex was reported to exhibit neuroprotective efficacy in several brain injury models. Here we investigate whether neonatal Dex administration promotes hippocampal neurogenesis and enhances hippocampus-dependent spatial learning and memory under physiological conditions. Methods: Postnatal day 7 (P7) pups were administered saline (vehicle control) or Dex (10, 20, or 40 µg/kg) by intraperitoneal injection. Neurogenesis and astrogenesis were examined in brain slices by BrdU immunostaining on P8 and changes in the expression levels of GDNF, NCAM, CREB, PSD95, and GAP43 were assessed by Western blotting on P35, respectively. Open field and Morris water maze (MWM) tests were conducted from P28 to P36 in order to assess effects on general motor activity and spatial learning, respectively. Results: Dexmedetomidine at 20 µg/kg significantly enhanced neurogenesis and astrogenesis in hippocampus and upregulated GDNF, NCAM, CREB, PSD95, and GAP43 compared to vehicle and other Dex doses. Moreover, 20 µg/kg Dex-injected rats showed no changes in motor or anxiety-like behavior but performed better in the MWM test compared to all other groups. Conclusion: Neonatal injection of Dex (20 µg/kg) enhances spatial learning and memory in rat pups, potentially by promoting hippocampal neurogenesis and synaptic plasticity via activation of GDNF/NCAM/CREB signaling.

“…The open field test (OFT) was undertaken as described previously (Kuniishi et al, 2017). The device contained a square arena (100 cm × 100 cm) surrounded by walls (40 cm high), which was divided into 16 equal squares and its central part occupied the four squares in the middle.…”

Section: Open Field Testmentioning

confidence: 99%

Bulleyaconitine A Exerts Antianxiety and Antivisceral Hypersensitivity Effects

Huang

Yang

et al. 2020

Front. Pharmacol.

Visceral pain is one of the leading causes for abdominal pain in gastroenterological diseases and is still hard to treat effectively. Bulleyaconitine A (BAA) is an aconitine analog and has been used for the treatment of pain. Our previous work suggested that BAA exerted analgesic effects on neuropathic pain through stimulating the expression of dynorphin A in spinal microglia. Here, we investigated the inhibitory effect of BAA on visceral pain and examined whether the expression of dynorphin A in spinal microglia was responsible for its effects. We found that BAA produced significant antivisceral pain effect induced by acetic acid through stimulating dynorphin A expression in spinal microglia. In addition, anxiety and chronic visceral pain are highly prevalent comorbid conditions in clinical research, which is still a problem to be solved. We also aimed to evaluate the effects of BAA on anxiety. A comorbidity model with characteristics of both chronic visceral pain and anxiety was developed by colorectal injection of 2,4,6-trinitrobenzene sulfonic acid and the induction of heterotypic intermittent chronic stress protocol. In comorbid animals, BAA exerted great antianxiety effects. Meanwhile, the antianxiety mechanism of BAA was different with the antivisceral pain mechanism of BAA. In conclusion, our study demonstrated, for the first time, that BAA exerted marked antivisceral pain and antianxiety effects, which expands the analgesic spectrum and clinical application of BAA. Furthermore, it also it provides a better guidance for the clinical use of BAA.