Endocrinology/Hormones

Gastric inhibitory polypeptide (GIP) is an inhibiting hormone of the secretin family of hormones. While GIP is a weak inhibitor of gastric acid secretion, its main role is to stimulate insulin secretion - in a glucose-dependent mechanism. Therefore, GIP is referred to as a glucose-dependent insulinotropic peptide. In GIP (Pro 3) the glutamic acid at position 3 has been substituted for a proline.GIP is derived from a 153-amino acid proprotein encoded by the GIP gene and circulates as a biologically active 42-amino acid peptide. It is synthesised by K cells, which are found in the mucosa of the duodenum and the jejunum of the gastrointestinal tract. GIP receptors are seven-transmembrane proteins found on β-cells in the pancreas. These β-cells are those that are able to simultaneously detect glucose and release insulin as a result to GIP binding.The clinical relevance of GIP is related to type 2 diabetes mellitus (T2DM)- studies have found that T2DM diabetics are unresponsive to GIP and have lower levels of GIP secretion after a meal when compared to non-diabetics. In research involving knockout mice, it was found that absence of the GIP receptors correlates with resistance to obesity.

The heptapeptide Alexamorelin is a member of the Growth Hormone secretagogues (GHS) family. These are synthetic molecules which act through the central nervous system to stimulate the secretion of somatotrophs, prolactin, adrenocorticotrophin and cortisol. Alexamorelin has also been shown to inhibit 125I-Tyr-Ala-HEX binding in tissues. Due to their stimulation of growth hormone release, they are known as non-approved pharmaceuticals and are a concern to sport's drug testing organisations.

ANP (9-22) is derived from the atrial natriuretic peptide (ANP) which is a cardiac hormone involved in maintaining cardio-renal homeostasis. This occurs through the activation of the guanylyl cyclase-coupled receptor, resulting in the increased concentration of cyclic guanylate monophosphate. Moreover its function in the processes of anti-proliferation and anti-angiogenesis allow it to take part in the cardiovascular remodelling process.ANP is a member of the natriuretic peptide family and it is encoded by the NPPA gene, located on chromosome 1. Once synthesized from the 151 amino acid pre-prohormone into its biologically active form, ANP is secreted by the atrial cardiomyocytes in the circulating forms: ANP (1-98) and ANP (99-126). This synthesis process involves the signal peptide being removed from the pre-prohormone resulting in proANP (1-126) which is converted into the circulating forms by the type II transmembrane serine protease Corin.

Mammalian bombesin-like neuropeptide- first isolated from pig spinal cord, which can stimulate rat uterine smooth muscle contraction and gastrin and somatostatin secretion in vitro. Increases blood pressure and pancreatic exocrine secretion in dogs.

Estrone-d2 is a deuterated compound of Estrone. Estrone has a CAS number of 53-16-7. Estrone is an aromatized C18 steroid with a 3-hydroxyl group and a 17-ketone, a major mammalian estrogen. It is converted from ANDROSTENEDIONE directly, or from TESTOSTERONE via ESTRADIOL. In humans, it is produced primarily by the cyclic ovaries, PLACENTA, and the ADIPOSE TISSUE of men and postmenopausal women.

Fulvestrant-d3 is a isotope labeled compound of Fulvestrant.an estrogen receptor (ER) antagonist and GPR30 agonist thatinduces apoptosis and autophagy.

AR antagonist 6 (compound 6i), a diphenyl ether androgen receptor (AR) antagonist, binds to the AR with an affinity of 120 nM. It demonstrates low toxicity and effective in vitro activity in the golden Syrian hamster ear model. [19] [1]