Pituitary gland Rathke's pouch. This contrasts with the posterior pituitary, which originates from neuroectoderm. Endocrine cells of the anterior pituitary are controlled by regulatory hormones released by parvocellular neurosecretory cells in the hypothalamic capillaries leading to infundibular blood vessels, which in turn lead to a second capillary bed in the anterior pituitary. This vascular relationship constitutes the hypothalamo-hypophyseal portal system. Diffusing out of the second capillary bed, the hypothalamic releasing hormones then bind to anterior pituitary endocrine cells, upregulating or downregulating their release of hormones. The anterior lobe of the pituitary can be divided into the pars tuberalis (pars glandularis) and pars
Pituitary apoplexy one of the nerves. In half of these cases, the oculomotor nerve (the third cranial nerve), which controls a number of eye muscles, is affected. This leads to diagonal double vision and a dilated pupil. The fourth (trochlear) and sixth (abducens) cranial nerves are located in the same compartment and can cause diagonal or horizontal double vision, respectively. The oculomotor nerve is predominantly affected as it lies closest to the pituitary. The cavernous sinus also contains the carotid artery, which supplies blood to the brain; occasionally, compression of the artery can lead to one-sided weakness and other symptoms of stroke.