Figure 5.26: How the hypothalamus controls pituitary hormones Specialized neurons in the hypothalamus, called neurosecretory cells, control the activity of the pituitary gland. Some neurosecretory cells secrete hormones directly into capillaries in the posterior pituitary, where they enter the general bloodstream. Others secrete hormones called releasing factors into a special capillary system that carries them to the anterior pituitary, where they stimulate the release of hormones manufactured there.