Ghrelin growth hormone secretagogue receptor, with the "GHS-R1b" splice being inactive) is involved in mediating a wide variety of biological effects of ghrelin, including: stimulation of growth hormone release, increase in hunger, modulation of glucose and lipid metabolism, regulation of gastrointestinal motility and secretion, protection of neuronal and cardiovascular cells, and regulation of immune function. They are present in high density in the hypothalamus and pituitary, on the vagus nerve (on both afferent cell bodies and afferent nerve endings) and throughout the gastrointestinal tract. Ghrelin promotes intestinal cell proliferation and inhibits apoptosis during inflammatory states and oxidative stress. It also suppresses
Corticotropin-releasing hormone receptor Corticotropin-releasing hormone receptor Corticotropin-releasing hormone receptors (CRHRs), also known as corticotropin-releasing factor receptors (CRFRs) are a G protein-coupled receptor family that binds corticotropin-releasing hormone (CRH). There are two receptors in the family, designated as type 1 and 2, each encoded by a separate gene ( and respectively). CRHRs are important mediators in the stress response. Cells in the anterior lobe of the pituitary gland known as corticotropes express the receptors and will secrete adrenocorticotropic hormone (ACTH) when stimulated. This binding of corticotropin releasing-hormone (CRH) activates the hypothalamic-pituitary-adrenal (HPA) axis, one of the two parts of the fight-or-flight response to stress.