The term magnocellular division of the paraventricular nucleus refers to one of three divisions of the paraventricular nucleus of the hypothalamus as defined by multiple methods in the rat. It is located in the medial zone of the anterior hypothalamic region dorsomedial to the anterior hypothalamic nucleus. It has three components: the anterior magnocellular part of the paraventricular nucleus, the medial magnocellular part of the paraventricular nucleus, and the posterior magnocellular part of the paraventricular nucleus. Functionally it and the parvicellular division of the paraventricular nucleus belong to the magnocellular neuroendocrine cell groups of the subcortical motor system. The third division, the descending division of the paraventricular nucleus, belongs to the behavior control column ( Swanson-2004 ).