In vitro the decarboxylation ofl-3,4-dihydroxyphenylalanine (DOPA) by total homogenate of rat liver and brain was markedly inhibited by 2.5 × 10−3M 3,4-dihydroxyphenylpyruvate, although the latter itself appeared to be aminated to a marked extent. In the homogenate or supernatant of various rat tissues, the decarboxylation of DOPA was not significantly affected by the simultaneous course of the DOPA-α-ketoglutarate-transamination.

In verschiedenen Hirnteilen des Kaninchens wurde nach i.v-Injektion vonDL-2-14C-3,4-Dihydroxyphenylalanin (14C-Dopa) die Radioaktivität der Fraktionen der aromatischen Aminosäuren, der Amine und der Oxydationsprodukte (z.B. Phenolcarbonsäuren) bestimmt. Klein- und Grosshirn enthielten relativ viel14C-Aminosäuren (wahrscheinlich vorwiegend Dopa) und wenig14C-Amine und -Phenolcarbonsäuren. Im Mes- und Diencephalon waren relativ viel14C-Oxydationsprodukte nachweisbar, während der Nucleus caudatus den höchsten14C-Amingehalt aufwies. Diese Abweichungen sind wahrscheinlich durch einen unterschiedlichen Dopa-Stoffwechsel bedingt, da die Total-Radioaktivität der einzelnen Hirnregionen 5 min nach der Injektion von14C-Dopa keinen signifikanten Unterschied aufwies.

In rats, three alpha-alkylated tryptamine derivatives (alpha-methyl, alpha-ethyl, and alphaalpha-dimethyltryptamine) caused alterations of 5-hydroxytryptamine metabolism typical of monoamine-oxidase inhibitors with short duration of action, viz., an increase of endogenous 5-hydroxytryptamine in brain, enhancement of the increase of 5-hydroxytryptamine in brain and heart after 5-hydroxytryptophan administration, an inhibition of the decrease in 5-hydroxytryptamine in brain induced by a benzoquinolizine derivative and of the increase induced by iproniazid. The increase after iproniazid was antagonized to the same extent by all the tryptamine derivatives and by harmaline, whereas dexamphetamine showed less effect. In the other experiments with brain, the tryptamine derivatives were less potent than harmaline, but somewhat more active than dexamphetamine. alpha-Methyltryptamine and alpha-ethyltryptamine were relatively more effective in the heart than in the brain. Among the tryptamine derivatives alphaalpha-dimethyltryptamine had the weakest activity in brain and in heart.

Journal of NeurochemistryVolume 6, Issue 3 p. 239-243 ACTIVITY OF MONOAMINE OXIDASE IN RELATION TO THE 5-HYDROXYTRYPTAMINE AND NOREPINEPHRINE CONTENT OF THE RAT BRAIN* K. F. Gey, K. F. Gey Medical Research Department of F. Hoffmann-La Roche & Co. Ltd., BaselSearch for more papers by this authorA. Pletscher, A. Pletscher Medical Research Department of F. Hoffmann-La Roche & Co. Ltd., BaselSearch for more papers by this author K. F. Gey, K. F. Gey Medical Research Department of F. Hoffmann-La Roche & Co. Ltd., BaselSearch for more papers by this authorA. Pletscher, A. Pletscher Medical Research Department of F. Hoffmann-La Roche & Co. Ltd., BaselSearch for more papers by this author First published: February 1961 https://doi.org/10.1111/j.1471-4159.1961.tb13471.xCitations: 38 * The results were partly reported in a preliminary form at the Meeting of the Swiss Society for Biochemistry, Zurich, May 30, 1959 (Gey and Pletscher, 1959). AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume6, Issue3February 1961Pages 239-243 RelatedInformation

INTRAPERITONEAL injection of 5-hydroxytryptophan (5HTP) shortly before death causes a considerable post-mortem rise of 5-hydroxytryptamine (5HT) in the brain of rats. This may be explained by the fact that 5HTP decarboxylation continues during the first few hours post-mortem whereas monoamine degradation by monoamine oxidase is probably considerably reduced1. In the work reported here the question was investigated whether this 5HTP induced post-mortem increase of brain 5HT might be used as a test for decarboxylase inhibitions. D,L-α-Methyl dihydroxyphenylalanine (α-methyl DOPA)2–6 served as a model inhibitor.

ACCORDING to a large number of reports, vegetable oils (such as corn, cotton-seed, rape-seed, safflower oil, etc.) are able to decrease serum cholesterol both in man and experimental animals. Some evidence exists that this effect is, at least partly, related to the presence of highly unsaturated fatty acids such as linoleic acid. It is not clear, however, whether such vegetable oils also have beneficial effects on arterio-sclerotic lesions. After cholesterol-feeding, conflicting results have been reported with rabbits as well as with cockerels. Experimental arteriosclerosis due to cholesterol-feeding may, however, be different from arteriosclerosis in man. Probably the spontaneous arteriosclerotic lesions in old birds, for example hens1, are more like human arteriosclerosis. We have therefore investigated the effect of dietary corn oil on spontaneous arteriosclerosis of old hens.

Ratten mit und ohne Iproniazid-Vorbehandlung erhielten 30 min vor Dekapitation 5-Hydroxytryptophan (5HTP) i. p. Das intakte Hirn wurde bis zu 4 h bei 37° C, Zimmertemperatur und in 0·1n HCl aufbewahrt. In allen Fällen ergab sich eine starke postmortale 5-Hydroxytryptamin (5HT)-Vermehrung im Gehirn.

Annals of the New York Academy of SciencesVolume 80, Issue 3 p. 555-567 AMINO ACID AND FATTY ACID HYDRAZIDES: CHEMISTRY AND ACTION ON MONOAMINE OXIDASE P. Zeller, P. Zeller Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorA. Pletscher, A. Pletscher Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorK. F. Gey, K. F. Gey Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorH. Gutmann, H. Gutmann Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorB. Hegedüs, B. Hegedüs Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorO. Straub, O. Straub Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this author P. Zeller, P. Zeller Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorA. Pletscher, A. Pletscher Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorK. F. Gey, K. F. Gey Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorH. Gutmann, H. Gutmann Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorB. Hegedüs, B. Hegedüs Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this authorO. Straub, O. Straub Research Department, F. Hoffmann-La Roche & Co., Ltd., Basel, SwitzerlandSearch for more papers by this author First published: September 1959 https://doi.org/10.1111/j.1749-6632.1959.tb49234.xCitations: 23AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume80, Issue3Amine Oxidase InhibitorsSeptember 1959Pages 555-567 RelatedInformation

AbstractThe influence of nearly all known physiological isoprene‐like carboxylic acids with 5 and 6 carbon atoms on the incorporation of [1‐14C]‐acetate into substances precipitated by digitonine was investigated by means of liver homogenates in buffers with various supplements.β,δ‐Dihydroxy‐β‐methylvaleric acid and β‐hydroxy‐ β‐methylglutaric acid appear to be the most closely related to the hypothetical isoprene unit; isovaleric acid, β, β‐dimethylacrylic acid and β‐hydroxyβ isovaleric acid appear to lie on a by‐path leading probably via β‐hydroxy‐β‐methylglutaric acid to cholesterol. Trans‐ and cis‐β‐methyl‐ glutaconic acid do not seem either to be necessary intermediates in cholesterol biosynthesis. β‐Methyl‐crotylaldehyde, β‐methyl‐crotyl‐ alcohol and isomylalcohol considerably inhibited the incorporation of acetate; however, it was uncertain whether this was due to a true inhibition or whether it indicates a metabolic pathway from isovaleric acid and β, β‐dimethylacrylic acid to cholesterol which does not proceed via β‐hydroxy‐β‐methylglutaric acid.

The action of blood sugar depressing sulfonylureas on glucose and oxygen uptake, as well as on glycogen content and formation of C14O2 from uniformly labelled C14-glucose was investigated in rat hemidiaphragms incubated in phosphate buffer. The following results were obtained: (1) Tolbutamide and Carbutamide increased the glucose uptake. (2) Tolbutamide decreased the glycogen-content. (3) Oxygen uptake as well as formation of C14O2 were increased by Tolbutamide. (4) The action of Tolbutamide and insuline was equal with respect to glucose uptake but different as regarding the glycogen content, oxygen uptake and CO2-formation.

AbstractLabeled cholesterol was prepared by incubation of rat liver homogenate with β‐hydroxy‐,β‐methyl‐δ‐valerolactone‐[2‐14C]. The partial degradation of the biosynthetic cholesterol shows the presence of activity in the carbon atoms 7, 22 and either 26 or 27, and absence of activity in the carbon atoms 20, 21, 23, 24, 25 and either 26 or 27. From these results it can be concluded that the normal sequence of isoprene units (head to tail) is achieved by condensation of the hydroxymethyl group of one molecule of β,δ‐dihydroxy‐β‐methylvaleric acid with the methylene group in α‐position to the carboxyl group of the next molecule.