Showing papers in "European Journal of Pharmacology in 1971"

TL;DR: In this article, the effects of six stimulants (amphetamine, methamphetamine, phenmetrazine, pipradrol, NCA and methylphenidate) on the brain dopamine and noradrenaline metabolism were investigated.

TL;DR: Results support an α-adrenergic component in the inhibitory effect of catapresan on vasomotor centres and in dogs, decrease in blood pressure, heart rate and aortic blood flow induced by intracisternal injection of piperoxane was reduced or reversed.

TL;DR: 3H-methylhistamine occurred more slowly in the newborn than in the adult rat brain, probably in relation with incomplete development of monoamine oxidase activity, and the efflux of 3H-deaminated metabolites from brain was not modified by treatment with probenecid.

TL;DR: At least part of this increase in DA turnover is due to a compensatory increase in the activity of DA neurons initiated by the DA receptor blockade caused by the neuroleptic drugs.

TL;DR: It is suggested that activation of α-adrenergic receptors in the brain induces sedation and the involvement of cholinergic pathways in mice for this effect.

TL;DR: Mianserin was more effective than cyproheptadine in counteracting tryptamine-induced responses in rabbits and rats and did not produce CNS depression, other than transient inhibition of the sensory activation of the EEG in rabbits.

TL;DR: The equivalent of p A 2 values were determined for morphine-naloxone in mice using the tail-flick, hot plate and writhing analgesic assays, which suggests that, in the case of morphine, the three analgesicAssays are probably measuring similar analgesic-receptor interactions.

TL;DR: The functional findings on rotational behaviour, reflex activity and locomotor behaviour show that the increased release of DA and NA induced by amantadine in the brain also results in increasedDA and NA receptor activity.

TL;DR: Doses of morphine became analgesic if rats had been previously stimulated in the nucleus raphe dorsalis but not after stimulation in the lateral nucleus raph dorsalis, and this effect may be related to a release of forebrain 5-HT.

TL;DR: The results suggest that the suppressive effect of small doses of morphine is mainly mediated through its facilitatory effect on the lower brain stem which has descending inhibitory influences on the spinal sensory transmission.

TL;DR: The results support the presence of a previously postulated interneuronal feedback mechanism in brain which can regulate dopamine synthesis and this may function at least in part through an effect on tyrosine hydroxylase activity.

TL;DR: With high doses, direct cardiodepressant actions of morphine may contribute to the fall in blood pressure and there is also evidence of direct peripheral release of catecholamines.

TL;DR: It is concluded that angiotensin increases the amount of transmitter released, per nerve impulse, from the sympathetic nerve terminals, and favoured the O-methylation of noradrenaline during nerve stimulation, probably by increasing the extraneuronal norad Renaline concentration.

TL;DR: Analysis of the tissues from the rat and dog indicated that the drug was completely cleared from the body, and salbutamol- 3 H inhaled by dogs and humans as an aerosol was slowly adsorbed from the lung, and excreted via the urine.

TL;DR: Assays of peripheral plasma corticosterone, 45 min after intraperitoneal injection of 2 to 16 mg/kg of Δ 1 -tetrahydrocannabinol (Δ 1 -THC), showed strong pituitary-adrenal activation which persisted undiminished after a week of daily doses.

TL;DR: Although responsiveness to footshock was not affected, preliminary results suggest that the drug exerts its effects on acquisition through an action on visual registration, and it seems that UCB 6215 enhances acquisition through its effect on registration mechanisms.

TL;DR: Either caffeine prevents the release of brain serotonin or is able to increase serotonin synthesis, as indicated by the concentration of 5-hydroxyindole acetic acid in the brain indicating that caffeine did not prevent serotonin deamination by monoamine oxidase.

TL;DR: The pathway in the metabolism of prostaglandins E 1 in kidney, spleen and liver from swine is oxidation of the 15-hydroxyl group to a ketone, reduction of the Δ 13 -double bond and stereospecific reduction ofThe 15-keto group to dihydro-prostaglandin E 1 (15 S).

TL;DR: The present findings indicate that the hypotensive effect of clonidine is due to stimulation of central NA receptor sites, and dopaminergic mechanism may also be involved in vasomotor regulation.

TL;DR: The results indicate involvement of adrenergic receptors in central vagus activity in pentobarbital anaesthetized dogs pretreated with the β-blocking agent Ko 592, and this effect was significantly antagonized by phentolamine.

TL;DR: The results are consistent with the concept that vasodilatation is associated with an increase and vasoconstriction with a decrease, in 3 H-cyclic AMP levels in vascular smooth muscle.

TL;DR: It is argued that the possible effectiveness of such drugs in migraine may not be due to antagonism of the actions of 5-HT, but could possibly result from a potentiation of the latter's vasoconstrictor effect in the external carotid bed.

TL;DR: Yohimbine, 5 or 20 mg/kg given intraperitoneally, increased the concentration of brain serotonin and decreased that of 5-HIAA, in the rat and could be considered as a potential tool to test the involvement of serotoninergic processes in endogenous depression.

TL;DR: It is suggested that the lesion alters the balanced control of motor output mediated by the basal ganglia and thereby the stimulatory effects of the neurotransmitter, dopamine, released by amphetamine from the corpus striatum.

TL;DR: Evidence was presented which indicated that the nicotine-induced elevation of arousal levels was correlated (at the 400 μg/kg dose) to an inhibition of 5-HT systems, which supports previous research in this laboratory which suggests that there may be a significant relationship between animal temperament and forebrain biogenic amine function.

TL;DR: Intraperitoneal injections of L-dopa decreased the concentrations of tryptophan, tyrosine and serotonin in rat brain in order to regulate the levels of serotonin and dopamine in the brain.

TL;DR: Histamine and betazole caused a biphasic blood pressure response in pigs which could explain the increase of blood pressure after injection of 48/80, and some of the other tissues studied showed decreased histamine concentrations.

TL;DR: It is concluded that adenosine exerts its effect on the heart rate by an extracellular site of action and may result from an inhibition of the uptake of the nucleoside into the tissues.

TL;DR: The results indicate that when an inhibitor of catecholamine synthesis is used to study norepinephrine disposition or synthesis in peripheral tissues both norpinephrine and epinephrine must be determined.

TL;DR: It is suggested that the polydipsia caused by isoprenaline and by lithium chloride is mediated through the release of renin, which increased significantly their water intake.