Pathway:
Cell bodies of hypothalamic neurons send axons inferiorly towards the pituitary gland.
Axons deliver hypothalamic hormones to the portal blood vessels
Hypothalamic-hypophyseal portal blood vessels deliver blood and hormonal signals from the hypothalamus to the pituitary gland (hypophysis). The the primary capillary plexus forms at the base of the hypothalamus (specifically, at the median eminence); it arises from the superior hypophyseal artery and drains, via portal vessels, inferiorly to the secondary capillary plexus, which bathes the endocrine cells of the anterior pituitary lobe.
The secondary capillary plexus delivers neurohormones that stimulate or inhibit hormonal secretion by the nearby anterior lobe endocrine cells.
Upon secretion, the anterior lobe hormones drain into systemic venous return to the heart; from here, they circulate within the systemic arterial blood to reach their target tissues.