+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Importance of tryptophan pyrrolase and aromatic amino acid decarboxylase in the catabolism of tryptophan

, : Importance of tryptophan pyrrolase and aromatic amino acid decarboxylase in the catabolism of tryptophan. Biochemical Pharmacology 27(5): 763-767

Benserazide, an inhibitor of aromatic amino acid decarboxylase, potentiates the rise of plasma tryptophan in rats given a tryptophan load. It also inhibits 14CO2 release from animals given carboxyl-labeled tryptophan. These results are explained by the ability of benserazide to inhibit tryptophan pyrrolase, the most important enzyme catabolizing tryptophan. Direct decarboxylation is not a quantitatively important pathway of tryptophan catabolism and carboxyl-labeled tryptophan is metabolized to 14CO2 primary by the pyrrolase pathway. These data have implications for the clinical use of tryptophan as an antidepressant. Pyridoxine, which is often given with tryptophan in clinical use, can activate aromatic amino acid decarboxylase. Pyridoxine does not inhibit the rise of plasma tryptophan in rats given a tryptophan load and is unlikely to antagonize the therapeutic effect of tryptophan. It may be possible to potentiate the therapeutic effect of tryptophan by administering it with benserazide to inhibit its peripheral catabolism through the pyrrolase pathway.


PMID: 77669

DOI: 10.1016/0006-2952(78)90517-8

Other references

Bailey, B.J.; Chalabi, Z.S., 1994: Improving the cost effectiveness of greenhouse climate control. A control philosophy is described for maximising the financial margin between the value of a greenhouse crop and the cost of controlling the greenhouse climate. This uses physical models, which describe how the conditions inside the greenhouse are...

Kalmar, J.A.; Cammoun, D.; Eick, J.J.; Connolly, E.S., 1986: Magnetic resonance imaging and cervical disc herniations. Journal of the Louisiana State Medical Society 138(10): 34-37

Grass, A., 1971: A barred owl record for Manning Park, BC. Murrelet, 52(2): 26

Schneider, L.S., 2016: WHO's dementia research priorities: a prescription for failure?. Lancet. Neurology 15(12): 1202-1203

Bacon, D., 2005: The 2004 AORN Salary Survey--trends among perioperative nurses. Estimating average compensation of perioperative nurses can be complicated because of nurses' unique workplace situations. For this salary survey, a multiple regression model was used to examine how a number of variables, including job title,...

Taglietti, V.; Tanzi, F.; Romero, R., 1983: Electrophysiological study of the frog egg at various stages of development. IV. Changes associated with the maturation process. The I/V relationship of frog oocytes is markedly modified following maturation, lacking the mature unfertilized egg cell membrane of K-selective channels and the leakage being strongly reduced. The only kind of voltage-dependent channels still pre...

Aune, T.M.; Pierce, C.W., 1983: Properties of the SIRS suppressor pathway. The SIRS suppressor pathway is initiated by activation of Ly 2+ T lymphocytes by either con A or IFN beta. SIRS is a protein which has been purified and exists as two species with mol. wts. of 14,000 and 21,500. The target of SIRS is the macrophag...

Nicholls, J.W.; Santer, L., 1961: A new tree-sampling device. The difficulties met with in using existing machine methods of increment-core sampling, viz. increasing frictional forces due to the inability of the tool to dispose of cutting waste, with subsequent degrade of the specimen through heating and com...

Del Bosco, Giovanni Fatta, 1967: Short note on arboriculture and scientific research in Tunisia. Tec Agr 19(2): 137-142

Lee, S.S.; Lin, M.T.; Liu, C.L.; Lin, Y.Y.; Liu, K.C., 1996: Six lignans from Phyllanthus myrtifolius. Six lignans comprising phyllamyricins D (1), E (2), and F (3) and phyllamyricosides A (4), B (5), and C (6) were isolated in a continuing study of Phyllanthus myrtifolius. Compounds 1 and 2 are 2a-methoxy-4-aryl-2,3-naphthalides. Compounds 3-6 bel...