Activation by S-adenosylhomocysteine of norepinephrine and serotonin in vitro uptake in synaptosomal preparations from rat brain

Summary S-Adenosylhomocysteine (10^–7–10^–5 M) activated norepinephrine (NE) and serotonin (5HT) in vitro uptake in synaptosomal preparations from rat brain, but did not affect dopamine (DA) uptake. When administered to rats (7 mg/kg i.p.), it had the same effect on in vitro NE and 5HT uptake. It did not affect NE and 5HT release.Work achieved within the frame of the research contract institut Mérieux., Institut National des Sciences Appliquées.     

Lysosome-rich synaptosomal preparations from rat mesencephalus (author's transl)]

Subcellular fraction, enriched with synaptosomes, obtained from rat brain has been found contaminated by lysosomes, as evidenced by the high content of acid phosphatase, their biochemical marker.     

Effects of S-adenosylmethionine and S-adenosylhomocysteine on in vivo synthesis of noradrenaline and serotonin in different parts of the rat brain]

S-adenosylmethionine (0,1 mg/kg/ip) decreases in vivo, norepinephrine (NE) synthesis and does not affect 5-hydroxytryptamine (5 HT) synthesis in the Rat brain. S-adenosylhomocysteine (7 mg/kg/ip) increases NE synthesis and decreases 5 HT synthesis. Neither nucleoside affects dopamine synthesis.     

5-hydroxytryptamine-sensitive adenylate cyclase activity in brain synaptosomal membrane preparations]

A serotonine-sensitive adenylate cyclase system has been observed in horse brain membrane preparations. In crude mitochondrial fraction two types of activation sites were characterized, the Ka being = 2 nM and 1 micrometer. In purified synaptosomal membranes, a single adenylate cyclase activation was observed corresponding to the highest apparent affinity (KD = 2nM). This activation site might be related to the high affinity binding site (KD = 2NM) were previously described in the same membrane preparations.     

Effect of lidoflazine on norepinephrine,angiotensin and serotonin responses in isolated smooth muscle preparations

Résumé Les effets de la lidoflazine ont été étudiés sur les bandelettes aortiques isolées du lapin et les bandelettes gastriques isolées du rat. La lidoflazine antagonise significativement la sérotonine sur ces 2 préparations sans altérer leurs réponses à l'angiotensine et à la noradrénaline.     

Effect of sulpiride on oxygen uptake by rat's brain tissue in vitro

Resumen El Sulpiride in vitro a la concentración de 1×10^–2 M disminuye el consumo de Oxígeno en cortes de cerebro de rata. El exceso de potasio o ausencia de calcio en el medio de incubación, no modifican este efecto. En homogeneizado de cerebro total, unicamente a la concentración de 1×10^–2 M deprime el consumo de oxígeno. A las concentraciones 1×10^–3 y 1×10^–4 M no modifica el consumo de oxígeno en cortes ni homogeneizados de cerebro.     

Effect of 5-hydroxydopamine on uptake and content of serotonin in rat striatum

Zusammenfassung 5-OH-Dopa und 5-OH-Dopamin senken in vivo den Serotoningehalt und vermindern in vitro dosisabhängig die Aufnahme von³H-Serotonin im Striatum von Ratten. Es kann daher angenommen werden, dass 5-OH-Dopamin in vivo überwiegend eine Verdrängung von Serotonin aus den serotoninergen Speichern verursacht, während in vitro zusätzlich eine Verdrängung von unspezifisch in katecholaminerge Speicher aufgenommenem Serotonin auftreten kann.     

Effect of mecloqualone on the oxygen and glucose uptake by brain tissue in vitro

Resumen La mecloqualona inhibe in vitro, la respiración de cortes y homogenizados de cerebro, incrementando el consumo de glucosa; este último efecto no se produce cuando al medio de incubación se añaden 100 mM de potasio.     

Effect of Ketamine hydrochloride on oxygen and glucose uptake by brain tissue in vitro

Resumen El clorhidrato de Ketamina (1×10^–3 M y 1×10^–4 M) incrementa el consumo de oxigeno de cortes de cerebro de rata incubados en Krebs-Ringer fosfato conteniendo 5 mM ó 100 mM de potasio. La droga no modifica el consumo de oxigeno de homogeneizado de cerebro total.     

Pharmacological effects of carbaryl II. Modification of serotonin metabolism in the rat brain

Zusammenfassung Nachweis, dass Carbaryl die Konzentration von Serotonin und 5-Hydroxyindolessigsäure im Rattenhirn steigert. Der Zusammenhang mit einem Stress wird als möglich angenommen.     

Effects of levophacetoperane, pemoline, fenozolone, and centrophenoxine on catecholamines and serotonin uptake in various parts of the rat brain]

These drugs, except centrophenoxine, inhibit in vitro in a competitive manner, norepinephrin uptake in Rat hypothalamus and cortex, and dopamine uptake in corpus striatum and cortex, at higher concentrations than d.l. amphetamine; this alone inhibits serotonin uptake in hypothalamus.     

The effects of physostigmine on the oxygen uptake in rat brain tissue.

Physostigmine in a dose of 0.1 mg/kg i.v. expressly stimulated the oxygen uptake in the rat cerebral cortex. This effect was blocked by propranolol and seems be mediated by catecholamines. Since atropine also antagonized the stimulant effect of physostigmine, it appears that the action of physostigmine is primarily cholinergic and that the adrenergic effect is a secondary phenomenon. The higher dose of physostigmine (0.4 mg/kg i.v.) caused a depression of rat brain oxygen uptake.     

The effect of adrenalectomy on the norepinephrine and serotonin content of the brain and on reserpine action in rats

Zusammenfassung Sieben Tage nach Adrenalektomie ist der 5-HT-Gehalt des Rattengehirns vermindert, während der NA-Gehalt unverändert bleibt. Chronische Hydrocortisonbehandlung restituiert, DOCA-Behandlung bleibt wirkungslos. Nach 5-HTP-Behandlung steigt der 5-HT-Gehalt auch im Gehirn der adrenalektomierten Tiere.     

Interaction of CDP-choline with synaptosomal transport of biogenic amines and their precursors in vitro and in vivo in the rat corpus striatum.

Added to a striatal synaptosomal homogenate of rat brain, CDP-choline 10(-4) M inhibits the uptake of norepinephrine (NE), dopamine (DA) and serotonin (5 HT) in a competitive fashion and enhances the uptake of tyrosine and tryptophan; administered to animals, CDP-choline (50 mg/kg/l h/i.v.) inhibits only the in vitro uptake of DA but enhances the uptake of precursors.     

Effect of des-Tyr1-gamma-endorphin on serotonin metabolism in rat brain regions

Intracerebroventricular (i.c.v.) administration of des-Tyr1-gamma-endorphin (0.1 and 1.0 microgram) caused a decrease of the serotonin (5-HT) concentration of the hippocampus. The concentration of 5-HIAA and the pargyline-induced alterations in 5-HT and 5-HIAA were not affected. No effects were noticed in other brain regions.     

The effects of various agents in vitro on homocarnosine-carnosine synthetase from rat brain

Summary The present paper reports the first evidence that homocarnosine-carnosine synthetase from rat brain requires free sulfhydryl groups for activity. The activity of the synthetase can be stabilized by dithioerythritol and inhibited strongly by Cu²⁺, Cd²⁺, Hg²⁺, Zn²⁺, and to a lesser extent by Ca²⁺, Ni²⁺, Li, chlorpromazine, -methyl DOPA and norepinephrine at the concentrations tested.Acknowledgment. This work was supported by United States Public Health Service Grant No. NS-06137.