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Gene & Protein in Disease Orexin in depression

Figure 6. Diagram of pathways involved in orexin signaling. Acting on presynaptic OX1R in the VTA, orexin can stimulate the release of glutamate onto
dopamine neurons to regulate complex behaviors and physiological processes related to arousal, motivation, reward, food intake, emotion, and cognition.
OX1R activation in dopamine neurons can recruit PLC, inhibiting the release of GABA from interneurons. (Created using Figdraw.com).
Abbreviations: AMPAR: Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor; BNST: Bed nucleus of the stria terminalis; CB1:
Cannabinoid receptor 1; CeA: Central nucleus of the amygdala; DR: Dorsal raphe; Hip: Hippocampus; KOP: κ-opioid receptors; LC: Locus coeruleus; LH:
Lateral hypothalamus; LHb: Lateral habenula nucleus; MOP: μ-opioid receptors; mPFC: Medial prefrontal cortex; NAc: Nucleus accumbens; NMDAR:
N-methyl-d-aspartic acid receptor; PLC: Phospholipase C; PVN: Hypothalamic paraventricular nucleus; VLPO: Ventrolateral preoptic area; VTA: Ventral
tegmental area; 2-AG: 2-Arachidonoylglycerol.

male rats induced by single prolonged stress (SPS) were diminished the behavioral alterations in SPS-exposed rats
observed through elevated cross-maze, sucrose water and partially recovered the increased OX1R level in the
preference, and wilderness experiments. Rats exposed to medial prefrontal cortex; these findings demonstrate that
SPS exhibited increased anxiety levels, reduced exploration PTSD symptoms associated with depression and anxiety
activities, and a lack of pleasure. Moreover, there was an are influenced by the orexin system. 55,56
increased OX1R expression in the medial prefrontal cortex A link between depression and the orexin system
and a decreased OXA expression in the hypothalamus as a may exist, and the pathological regulation of depression
consequence of SPS. Lateral ventricular injection of OXA may relate to orexin. Acquired helplessness (AH)
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Volume 4 Issue 2 (2025) 8 doi: 10.36922/gpd.4210