Corticotropin-releasing factor (CRF) has been widely implicated as playing a major role in modulating the endocrine, autonomic, behavioral and immune responses to stress. Corticotropin Releasing Factor (CRF) is a hypothalamic peptide that releases adrenocorticotropic hormone (ACTH) and endorphin from the anterior pituitary. Corticotropin Releasing Factor (CRF) is also a neurotransmitter in the central nervous system, and is involved in autonomic and endocrine responses to stress.