The hypothalamus controls secretion by the adenohypophysis by

A) direct neural stimulation.

B) indirect osmotic control.

C) secreting releasing and inhibiting factors into a tiny portal system.

D) altering ion concentrations and pH in the anterior pituitary.

E) gap synaptic junctions.

The correct answer is: C) secreting releasing and inhibiting factors into a tiny portal system.

Hypothalamus is part of the brain that consists of many nuclei and has the function to connect the nervous system to the endocrine system via the pituitary gland. Hypothalamus is linked with the anterior pituitary via hypothalamic-adenohypophyseal axis. Releasing hormones or factors produced in hypothalamic nuclei are first released from the prolongation of the hypothalamus and then into a tiny portal system called hypophyseal portal system. This system of blood vessels transports hormones to the anterior pituitary where they act on the secretion of adenohypophyseal hormones.