The involvement of 5-hydroxytryptaminergic (5-HT) system for the Ptychodiscus brevis toxin (PbTx)-induced depression of spinal reflexes was evaluated. The reflex potentials were recorded at ventral root by stimulating the corresponding dorsal root in neonatal rat spinal cord in vitro. Superfusion of PbTx (2.8-84microM) depressed the monosynaptic (MSR) and polysynaptic (PSR) reflexes in a concentration-dependent manner. The depression of the reflexes was maximal with 84microM of the toxin. Ondansetron (0.1microM), a 5-HT(3) receptor antagonist, blocked the PbTx-induced depression of MSR and PSR. Spiperone (a 5-HT(2A) antagonist) or ketanserin (5-HT(2A/2C) antagonist and also at 5-HT(1B/1D)) failed to block the PbTx-induced depression of the reflexes. The 5-HT concentration of the cords was increased by four-fold after exposure to PbTx (28microM) and the increase was not seen in the cords pretreated with dl-2 amino-5-phosphonovaleric acid (APV, a NMDA receptor antagonist). Superfusion of 5-HT or phenylbiguanide (PBG, a 5-HT(3) receptor agonist) also produced depression of the spinal reflexes in a concentration-dependent manner. The 5-HT-induced depression of reflexes was blocked by ondansetron but not by spiperone. The results demonstrate that the PbTx-induced depression of spinal reflexes involves 5-hydroxytryptamine via 5-HT(3) receptors modulated by NMDA receptor.
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http://dx.doi.org/10.1016/j.neulet.2006.09.019 | DOI Listing |
Cogn Affect Behav Neurosci
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School of Psychology, Shandong Second Medical University, 7166# Baotong West Street, Weifang, Shandong, 261053, P. R. China.
Background: Post-traumatic stress disorder (PTSD) is a serious psychiatric disorder that occurs after an individual has witnessed or experienced a major traumatic event. Emotional contagion seems to play an important role in witnessing trauma, highlighting the importance of understanding the neurobiological consequences of psychological or emotional stress and its impact on the individual's mental health. Therefore, understanding the relationship between emotional contagion and PTSD susceptibility and the abnormal neurobiological and behavioral changes behind it could help find effective molecular treatment targets.
View Article and Find Full Text PDFSci Rep
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Department of Anesthesiology, Cangzhou Central Hospital, Cangzhou, China.
The potential role of hydrogen sulfide (HS) in the modulation of neuropathic pain is increasingly recognized. This study investigated the therapeutic effect of intraperitoneal injection of the HS donor sodium hydrosulfide (NaHS) on neuropathic pain. Utilizing the spared nerve injury (SNI) model in mice, the research investigates the role of astrocytes and the excitatory neurotransmitter glutamate in chronic pain.
View Article and Find Full Text PDFWorld J Psychiatry
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Pain Ward of Orthopedics Department of TCM, Honghui Hospital, Xi'an Jiaotong University, Xi'an 710054, Shaanxi Province, China.
Background: Traumatic injuries, such as falling, car accidents, and crushing mostly cause spinal fractures in young and middle-aged people, and > 50% of them are thoracolumbar fractures. This kind of fracture is easily combined with serious injuries to peripheral nerves and soft tissues, which causes paralysis of the lower limbs if there is no timely rehabilitation treatment. Young patients with thoracolumbar fractures find it difficult to recover after the operation, and they are prone to depression, low self-esteem, and other negative emotions.
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Pharmacology and Therapeutics, School of Medicine, University of Galway, Galway, Ireland.
Paclitaxel (PTX) is a commonly used chemotherapeutic drug, however, one of its major adverse effects is chronic neuropathic pain, with the incidence being higher in women than in men. The neurobiological mechanisms behind this sex difference are still largely unclear, and the endocannabinoid system, which exhibits sexual dimorphism and plays a key role in pain regulation, is a promising area for further studies. The present study aimed to characterise pain-, cognition-, anxiety-, and depression-related behaviours in male and female rats following PTX administration, and associated alterations in the endocannabinoid system.
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