果糖暴食对大鼠下丘脑外侧核与伏隔核 Orexin 神经元的影响.

Objective: To investigate whether the rats given glucose in the intermittent access model(IAM) can cause hedonic feeding including bingeing, and the influence of nucleus accumbens and lateral hypothalamic(LHA) orexin(ORX)neurons on fructose eating behavior. Methods: The IAM rats were given 4 %, 8 % or 12 % fructose or Saline(NS). And the fructose intake and fructose eating behavior were observed and recorded in the rats. The receptors number(Bmax) and receptor affinity(Kd) of dopamine D1R and D2R were analyzed in the nucleus accumbens shell, nucleus accumbens core and dorsal striatum. The C-Fos neurons immunoreactivity(Fos-IR)were recorded in paraventricular nucleus, amygdala, nucleus accumbens of related nucleus of the long-term and short-term IAM rat. Food intake was observed while administration of OX1 R antagonist SB334867 in the long term IAM rats. Results: The rats given fructose solutions displayed fructose bingeing but unaltered DA D1R or D2R number following long-term exposure to the IAM. Fructose bingeing rats, as compared to chow bingeing controls, exhibited reduced nucleus accumbens neuron activation, as determined by c-Fos-immunoreactivity. Following short-term access to the IAM, rats exhibited bingeing but unchanged Fos-IR. Fructose bingeing and food intake were significantly reduced while OX1 R antagonist SB-334867(30 mg/kg) were administrated for 21 days in the IAM rats.Conclusion: Long-term fructose bingeing can increase the release of Orexin, reduce the nucleus accumbens Orexin neuron activation,enhance the lateral nucleus Orexin neurons activation. [ABSTRACT FROM AUTHOR]