Department of Pharmacology and Brain Biostructure, Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Street, Kraków, 31-343, Poland.
Department of Drug Addiction Pharmacology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12 Street, Kraków, 31-343, Poland.
Psychopharmacology (Berl). 2024 Dec;241(12):2585-2607. doi: 10.1007/s00213-024-06705-7. Epub 2024 Oct 27.
The literature indicates that nicotine exposure or its discontinuation impair adult hippocampal neurogenesis in rats, though the impact of exercise on this process remains unclear. We have previously shown that disturbances in the number of doublecortin (DCX, a marker of immature neurons)-positive (DCX) cells in the dentate gyrus (DG) of the hippocampus during nicotine deprivation may contribute to a depression-like state in rats.
This study aimed to investigate the effect of running on hippocampal neurogenesis, depression-like symptoms, and drug-seeking behaviour during nicotine deprivation.
The rats were subjected to nicotine (0.03 mg/kg/inf) self-administration via an increasing schedule of reinforcement. After 21 sessions, the animals entered a 14-day abstinence phase during which they were housed in either standard home cages without wheels, cages equipped with running wheels, or cages with locked wheels.
Wheel running increased the number of K-67 and DCX cells in the DG of both nicotine-deprived and nicotine-naive rats. Wheel-running exercise evoked an antidepressant effect on abstinence Day 14 but had no effect on nicotine-seeking behaviour on abstinence Day 15 compared to rats with locked-wheel access.
In summary, long-term wheel running positively affected the number of immature neurons in the hippocampus, which corresponded with an antidepressant response in nicotine-weaned rats. One possible mechanism underlying the positive effect of running on the affective state during nicotine cessation may be the reduction in deficits in DCX cells in the hippocampus.
文献表明，尼古丁暴露或戒断会损害大鼠海马体中的成年神经发生，尽管运动对这一过程的影响尚不清楚。我们之前已经表明，在尼古丁剥夺期间，海马齿状回（DG）中双皮质素（DCX，不成熟神经元的标志物）阳性（DCX）细胞数量的紊乱可能导致大鼠出现类似抑郁的状态。
本研究旨在探讨跑步对海马神经发生、抑郁样症状和尼古丁剥夺期间觅药行为的影响。
大鼠通过递增强化方案进行尼古丁（0.03mg/kg/inf）自我给药。21 个疗程后，动物进入为期 14 天的戒断期，在此期间，它们被安置在没有轮子的标准笼中、配备跑步轮的笼中或轮子被锁定的笼中。
轮跑增加了尼古丁剥夺和未剥夺大鼠 DG 中的 K-67 和 DCX 细胞数量。与锁定轮接触的大鼠相比，轮跑在戒断第 14 天对抑郁有抗抑郁作用，但对戒断第 15 天的尼古丁觅药行为没有影响。
总之，长期轮跑积极影响了海马体中不成熟神经元的数量，这与尼古丁戒断大鼠的抗抑郁反应相对应。跑步对尼古丁戒断期间情绪状态的积极影响的一种可能机制可能是减少海马体中 DCX 细胞的缺陷。
