Gastrointestinal peptide-hormone

New initiatives towards the development of anorectic treatments for obesity are centring on satiety mechanisms of some gastrointestinal peptide hormones, especially within the CNS, including amylin, CCK, and bombesin-like peptides. See amylin receptor agonists cholecystokinin RECEPTOR agonists bombesin receptor agonists. 

Cholecystokinin (CCK) is a 33 amino acid gastrointestinal peptide hormone of that was originally isolated from porcine gut and was given its name "the gallbladder mover" due to its ability to stimulate bile flow [1],... 

The substrates studied include the carboxy terminal seven residues of the gastrointestinal peptide hormone cholecysto-kinin, denoted CCK7, with sequence ... 

The principal hormones of the human posterior pituitary include the two nonapeptides, oxytocin [50-56-6] and arginine vasopressin [11000-17-2] (antidiuretic hormone, ADH). Many other hormones, including opioid peptides (see Opioids, endogenous), cholecystokinin [9011-97-6] (CCK) (see Hormones, BRAIN oligopeptides), and gastrointestinal peptides, also have been located in mammalian neurohypophysis (6), but are usually found in much lower concentrations (7). Studies have demonstrated that oxytocin and vasopressin are synthesized in other human organs, both centrally and peripherally, and there is considerable evidence for their role as neurotransmitters (see Neuroregulators) (8). 

A further type of PM-located GC is gastrointestinal (GI) C-type GC that is activated by the paracrine peptide hormone guanylin. Guanylin is secreted by GI cells and resultant GC activation and cGMP elevation results in increased Cl transport via the cystic fibrosis transmembrane conductance regulator (CFTR) into the intestinal lumen with resultant increased water flow. The Escherkhia coli heat-stable enterotoxin mimics guanylin in activating this intestinal C-type GC and consequently causes diarrhoea. 

Peptide-hormones like hypothalamus-pituitary, gastrointestinal, parathyroid, neurohormones, Gfs related peptide-hormones cannot penetrate the plasma membrane and their receptors are located on the cell surface and the signal transport to the nucleus is becoming via a second messenger. The main hormone action seems to be DNA synthesis whereas other including mediation of neurotransmission, enzyme synthesis, regulation and synthesis of structural proteins are responsible for the specific characteristics of differentiated cell. 

Motilin is a 22-amino acid peptide hormone found in the gastrointestinal (GI) M cells, as well as in some... 

Pancreatic polypeptide Gastrointestinal peptide Vasoactive intestinal polypeptide Kidney hormones Renin... 

Irrespective of the validity of the hypothetical membrane-bound pathway great efforts have been made in the last few years to determine preferred conformations of peptide hormones in media mimicking the more hydrophobic environments of membranes and/or receptor binding clefts. Our contributions in this field of research are confined to a pair of closely related gastrointestinal hormones, i.e. to gastrin and cholecystoklnin (CCK), which were chosen as model bioactive peptides. 

Motilin (Mot), FVPIFTYGEL QRMQE KERNK GQ, a 22-peptide hormone belonging to the —r ghrelin family. MotUin stimulates the contraction of smooth muscle in the gastrointestinal tract. MotUin was originally isolated from porcine gut. 

When Bruckner accepted the invitation to work in Budapest, peptide chemistry did not come to a halt in Szeged. Led by his former associate K. Kovacs, an active research group is engaged in synthesis and study of peptide hormones. The contributions of L. Balaspiri and B. Penke to the chemistry of gastrointestinal peptides are certainly noteworthy. 

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