What is the Origin of GHSR1a?

The acronym GHSR1a stands for Growth Hormone Secretagogue Receptor type 1a, reflecting its original identification as the receptor for synthetic molecules that stimulated GH release. Its endogenous ligand, ghrelin, was later discovered, cementing the receptor's role in the somatotropic axis. The nomenclature emphasizes its key function in initiating the secretion of growth hormone.

What is the Mechanism of GHSR1a?

Ghrelin binding to the GHSR1a receptor initiates an intracellular signaling cascade, primarily through the Gq/11 protein pathway, which increases intracellular calcium concentration. This rise in calcium is the direct stimulus for the somatotroph cells in the anterior pituitary to release growth hormone into the circulation. Furthermore, activation of GHSR1a in the hypothalamus modulates neuropeptide release, driving the sensation of hunger and influencing overall energy expenditure. The receptor's constitutive activity is also a notable feature.

GHSR1a

Meaning

GHSR1a, or Growth Hormone Secretagogue Receptor type 1a, is a G protein-coupled receptor that serves as the primary receptor for the endogenous hormone ghrelin. This receptor is predominantly expressed in the pituitary gland and the hypothalamus, where its activation plays a central role in regulating the pulsatile release of growth hormone (GH) and stimulating appetite. Its function is therefore crucial in the neuroendocrine control of energy balance, growth, and metabolism. GHSR1a is a key pharmacological target for managing appetite and growth disorders.