Tetragastrin is commonly used in scientific research to induce panic attacks
ASPARTAME WAS DISCOVERED IN 1965 BY JAMES M. SCHLATTER, A CHEMIST WORKING FOR G.D. SEARLE & COMPANY. SCHLATTER SYNTHESIZED ASPARTAME AS AN INTERMEDIATE STEP IN GENERATING A TETRAPEPTIDE OF THE HORMONE GASTRIN, FOR USE IN ASSESSING AN ANTI-ULCER DRUG CANDIDATE. HE DISCOVERED ITS SWEET TASTE WHEN HE LICKED HIS FINGER, WHICH HAD BECOME CONTAMINATED WITH ASPARTAME, TO LIFT UP A PIECE OF PAPER.
WIKIPEDIA, ASPARTAME PAGE
- Tetragastrin (N-((phenylmethoxy)carbonyl)-L-tryptophyl-L-methionyl-L-aspartyl-L-phenylalaninamide) is the C-terminal tetrapeptide of gastrin. It is the smallest peptide fragment of gastrin which has the same physiological and pharmacological activity as gastrin.
- Cholecystokinin tetrapeptide (CCK-4, Trp–Met–Asp–Phe-NH2) is a peptide fragment derived from the larger peptide hormone cholecystokinin. Unlike cholecystokin which has a variety of roles in the gastrointestinal system as well as central nervous system effects, CCK-4 acts primarily in the brain as an anxiogenic, although it does retain some GI effects, but not as much as CCK-8 or the full length polypeptide CCK-58.
- CCK-4 reliably causes severe anxiety symptoms when administered to humans in a dose of as little as 50μg,
- Eser D, di Michele F, Zwanzger P, Pasini A, Baghai TC, Schüle C, et al. (January 2005). “Panic induction with cholecystokinin-tetrapeptide (CCK-4) Increases plasma concentrations of the neuroactive steroid 3alpha, 5alpha tetrahydrodeoxycorticosterone (3alpha, 5alpha-THDOC) in healthy volunteers”. Neuropsychopharmacology. 30 (1): 192–5. doi:10.1038/sj.npp.1300572. PMID 15467707.
- and is commonly used in scientific research to induce panic attacks for the purpose of testing new anxiolytic drugs.
- Bradwejn J (July 1993). “Neurobiological investigations into the role of cholecystokinin in panic disorder”. Journal of Psychiatry & Neuroscience. 18 (4): 178–88. PMC 1188527. PMID 8104032.
- Schunck T, Erb G, Mathis A, Gilles C, Namer IJ, Hode Y, et al. (July 2006). “Functional magnetic resonance imaging characterization of CCK-4-induced panic attack and subsequent anticipatory anxiety”. NeuroImage. 31 (3): 1197–208. doi:10.1016/j.neuroimage.2006.01.035. PMID 16600640. S2CID 2430104.
- Eser D, Schüle C, Baghai T, Floesser A, Krebs-Brown A, Enunwa M, et al. (July 2007). “Evaluation of the CCK-4 model as a challenge paradigm in a population of healthy volunteers within a proof-of-concept study”. Psychopharmacology. 192 (4): 479–87. doi:10.1007/s00213-007-0738-7. PMID 17318504. S2CID 21457632.
- Eser D, Leicht G, Lutz J, Wenninger S, Kirsch V, Schüle C, et al. (February 2009). “Functional neuroanatomy of CCK-4-induced panic attacks in healthy volunteers”. Human Brain Mapping. 30 (2): 511–22. doi:10.1002/hbm.20522. PMC 6870703. PMID 18095276.
- Since it is a peptide, CCK-4 must be administered by injection, and is rapidly broken down once inside the body so has only a short duration of action,
- See also Pentagastrin
- Pentagastrin (trade name Peptavlon) is a synthetic polypeptide that has effects like gastrin when given parenterally.
- Braganza JM, Herman K, Hine P, Kay G (April 1979). “The effect of pentagastrin (I.C.I. 50, 123) on peptic secretion in man”. The Journal of Physiology. 289: 9–16. doi:10.1113/jphysiol.1979.sp012721. PMC 1281354. PMID 379305.
- It stimulates the secretion of gastric acid, pepsin, and intrinsic factor, and has been used as a diagnostic aid as the pentagastrin-stimulated calcitonin test.
- Pentagastrin binds to the cholecystokinin-B receptor, which is expressed widely in the brain. Activation of these receptors activates the phospholipase C second messenger system. When given intravenously it may cause panic attacks.
- Pentagastrin’s IUPAC chemical name is “N-((1,1-dimethylethoxy)carbonyl)-beta-alanyl-L-tryptophyl-L-methionyl-L-alpha-aspartyl-L-phenylalaninamide”.
- Pentagastrin stimulation test
- Pentagastrin is also used as a stimulation test to elevate of several hormones, such as serotonin. It provokes flushing and is useful in evaluating patients who describe flushing, but have normal or only marginally elevated biochemical markers for carcinoid syndrome.[citation needed]
- It has been used to stimulate ectopic gastric mucosa for the detection of Meckels diverticulum by nuclear medicine.[citation needed]
- Calcitonin test
- The pentagastrin-stimulated calcitonin test is a diagnostic test for medullary carcinoma of the thyroid (MTC). MTC is a malignancy of the calcitonin-secreting cells of the thyroid gland, and thus MTC is commonly associated with an elevated calcitonin level, but an elevated level may not always be obvious. The pentagastrin-stimulated calcitonin test is useful in cases of suspected MTC that are not associated with elevated calcitonin. In these patients, injecting pentagastrin will cause calcitonin levels to rise significantly above the normal or basal range.
- Barbot N, Calmettes C, Schuffenecker I, Saint-André JP, Franc B, Rohmer V, et al. (January 1994). “Pentagastrin stimulation test and early diagnosis of medullary thyroid carcinoma using an immunoradiometric assay of calcitonin: comparison with genetic screening in hereditary medullary thyroid carcinoma”. The Journal of Clinical Endocrinology and Metabolism. 78 (1): 114–20. doi:10.1210/jcem.78.1.7904611. PMID 7904611.
- After a total thyroidectomy for medullary thyroid carcinoma, the pentagastrin-stimulated calcitonin release can be used to detect residual parafollicular C-cells.
- See also
- Pentagastrin (trade name Peptavlon) is a synthetic polypeptide that has effects like gastrin when given parenterally.
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From Wikipedia where the main page was last updated July 2, 2022
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