Endocrine and Releasing factor

Endocrine noun - Any of the glands of the endocrine system that secrete hormones directly into the bloodstream.

Releasing factor and endocrine are semantically related. In some cases you can replace phrase "Releasing factor" with "Endocrine", this terms are similar.

Releasing factor noun - Any of several hormones produced in the hypothalamus and carried by a vein to the anterior pituitary gland where they stimulate the release of anterior pituitary hormones; each of these hormones causes the anterior pituitary to secrete a specific hormone.

Endocrine and releasing factor are semantically related. You can use "Endocrine" instead a noun phrase "Releasing factor".