Obese female Zucker rats (fa/fa) exhibit dendritic retraction in neurons in the ventromedial hypothalamic nucleus

•Female Zucker rats show dendritic retraction in the ventromedial hypothalamic nucleus.•Neurons of the ventromedial hypothalamic nucleus are small in female Zucker rats.•Female Zucker rats show few dendritic arbors within the VHM nucleus.•The dendritic length of VMH neurons in female Zucker rats is reduced.•Changes exist in the neurons of the circuit that regulate food intake in obese rats. The ventromedial hypothalamic nucleus (VMH) is located in the tuberal region of the hypothalamus and is traditionally considered the satiety center. In obese Zucker rats, which express a mutation in the leptin receptor gene and exhibit obesity from the first weeks of life, the morphology of VMH neurons is unknown. In the present study, we found that the dendritic length of VMH neurons in obese Zucker rats was significantly shorter than that in Long Evans rats. This finding allows us to suggest that obese Zucker rats exhibit both neuronal metabolic alterations related to leptin and a reduction in the flow of information within the neuronal circuits in which the VMH nucleus participates to regulate foraging.