Cholecystokinin-pancreozymin CCK

The conclusion that a peptide such as bradykinin consisting of nine amino acids does not have a preferred conformation but that a well defined geometry develops from a certain chain length on (secretin contains twenty-seven amino acids, glucagon with fairly similar sequence and somewhat similar spectra twenty-nine amino acids), would be attractive but is not well founded. Examination of the ORD and CD spectra of the intestinal hormone cholecystokinin-pancreozymin (CCK), a single chain peptide of 33 amino acids, gives no evidence for structural rigidity which would express itself in spectra similar to those of helical molecules. 

Cholecystokinin (= Pancreozymin)] (4kDa protein) Animals brain GI tract CCK-R agonist ianorexigenic, nociception, T pancreatic exocrine secretion, J- gastric emptying]... 

Evidently there is in the three different dilutions no considerable difference between the two preparations as to pancreozymin activity, and the ratio cholecystokinin pancreozymin will be the same. The pancreozymin activity is proportional to the amount of cholecystokinin injected, irrespective of the degree of purity of the preparation of 0. 3 or 220 Ivy dog units of CCK per mg. Thus, on increasing the cholecystokinin activity of the preparation about 650 times there is an equal rise in the pancreozymin activity (Jorpes and Mutt 1966). 

Cholecystokinin, CCK or pancreozymin (gallbladder, pancreas), many forms exist CCK 58 58 ... 

C-terminal octapeptide SQ 19844 Kinevac. C H N -OjjS mol wt [143.29. C 51.48%, H 5.47%, N 12.25%, O 22.39%, S 8.41%. The C-terminal octapeptide of choleeys-tokinin-pancreozymin (see cholecystokinin). Structurally similar to caerulein, q.v., it evokes a variety of biological responses similar to CCK-PZ, includiug smooth-muscle contraction of the gall bladder and small intestine, relaxation of the choledochoduodenal junction, protein secretion by the pancreas and acid secretion by the stomach. It is more active than cholecystokinin on a weight or molar basis. Initial isoln V. Mutt, J. E. Jorpes, Eur. J. Biochem. 6, 156 (1968). Prepn M. A. Ondetti et al. Get. pat. 1,922,185 corresp to U.S. pat, 3,723,406 (1969, 1970, both to Squibb) eidem, J. Am. Chem. Soc. 92, 195 (1970), Mechanical and metabolic effects K. E. Andersson ef al., Acta Physiol... 

Pancreozymin. As pointed out by the present authors in 1961 and 1962, it is quite remarkable how closely cholecystokinin and pancreozymin accompany each other during the various purification steps, whereas secretin separates very early. This applies to the chromatography on the acidic carboxymethyl cellulose and on the basic TEAE-cellulose up to a strength of 200-250 Ivy dog units of CCK per mg substance. 

At this stage of purity we determined the pancreozymin activity of the cholecystokinin preparations and the ratio CCK PZ was compared with that in Harper and Raper s original pancreozymin preparation, given to us by professor Harper in 1959, as well as in a recent sample of Pancreozymin Boots, The two last ones had about the same CCK activity, 0. 3 Ivy dog units per mg dry substance. 

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