Final answer:
Neurons in the hypothalamic-hypophyseal tract secrete oxytocin and antidiuretic hormone (ADH), also known as vasopressin. These hormones are transported to and stored in the posterior pituitary gland and released into the bloodstream.
Step-by-step explanation:
Neurons whose axons travel in the hypothalamo-hypophyseal tract include those that secrete oxytocin and vasopressin (also known as Antidiuretic Hormone, ADH). These neurons originate in the hypothalamus, specifically within the paraventricular and supraoptic nuclei. Their axons descend through the hypothalamic-hypophyseal tract and terminate in the posterior pituitary, where these hormones are stored and eventually released into the bloodstream.
The release of oxytocin and ADH into the blood occurs via neural signaling from the hypothalamus. While oxytocin is primarily associated with labor and milk ejection in lactating women, ADH plays a crucial role in water reabsorption in the kidneys, affecting blood pressure and overall fluid balance in the body.