Showing papers by "Serge Gauthier published in 1981"
TL;DR: A significant difference between mean baseline scores and treatment scores was found on tests of new learning ability, indicating a practice effect in outpatients with Alzheimer disease of moderate severity, but there were no differences between mean placebo and lecithin scores on any of the psychological test measures.
Abstract: Eleven outpatients with Alzheimer disease of moderate severity completed a double-blind placebo-controlled crossover trial of lecithin. Each patient received 10 gm three times daily of a placebo for 3 months. Plasma choline levels rose threefold and remained at that level throughout the lecithin administration period. A significant difference between mean baseline scores and treatment scores was found on tests of new learning ability, indicating a practice effect in these tests. However, there were no differences between mean placebo and lecithin scores on any of the psychological test measures.
67 citations
TL;DR: The data presented here suggest that control of human brain 5HT synthesis by precursor availability is similar to that in the rat, and that tryptophan administration increases indoleamines function, as well as indoleamine synthesis, in depressed patients.
Abstract: Administration of tryptophan to the rat results in an increased synthesis of 5-hydroxytryptamine (5HT) in the brain. (Ashcroft et al., 1965), because the rate-limiting enzyme in 5HT synthesis, tryptophan hydroxylase, is not normally saturated with tryptophan (Friedman et al., 1972). This is important physiologically as amounts of tryptophan as small as one twentieth of a rat’s normal daily intake can result in a significant rise of plasma and brain tryptophan and of brain 5HT (Fernstrom and Wurtman, 1971). In humans, as in rats, tryptophan administration will increase CNS 5HT synthesis (Eccleston et al.,1970). The fact that the level of a dietary component (tryptophan) can control the synthesis of a neurotransmitter (5HT) that is implicated in the control of various aspects of mood and the etiology of neuropsychiatric disorders is of obvious interest. Therefore we have attempted to gain more information on the role of tryptophan availability in controlling indoleamine synthesis and function in human CNS. The specific questions we have attempted to answer for humans are: (i) What is the relationship between plasma and brain tryptophan? (ii) Is control of the brain 5HT by tryptophan availability physiologically important? (iii) Is tryptophan availability important in controlling the synthesis of a related indoleamine, tryptamine? (iv) To what extent can tryptophan administration influence brain 5HT and tryptamine synthesis? (v) Can tryptophan administration influence indoleamine function as well as indoleamine synthesis?
31 citations
TL;DR: A patient representing with palatal myoclonus was diagnosed as suffering from possible multiple sclerosis and a reduction of cerebrospinal 5-hydroxy-indole-acetic acid suggested a decreased central serotonergic turnover.
Abstract: A patient representing with palatal myoclonus was diagnosed as suffering from possible multiple sclerosis. A reduction of cerebrospinal 5-hydroxy-indole-acetic acid suggested a decreased central serotonergic turnover. A therapeutic trial with clonazepam, a serotonergic agonist, improved the myoclonus symptomatically. The possible involvement of serotonergic inhibitory systems in the expression of palatal myoclonus is discussed.
12 citations
01 Jan 1981
TL;DR: The role of central nervous pathways in this induction of adrenal TH is delineated, with Identified central transmitters involved in this process include: inhibitory serotonergic systems (partially localized in the medial raphe nucleus), and excitatory dopaminergic path(s) (Lewander et al., 1977; Quik and Sourkes, 1977).
Abstract: The regulation of adrenal medullary tyrosine hydroxylase (TH, tyrosine 3-monooxygenase, EC 1.14.16.2) involves predominantly two neural mechanisms: (1) rapidly acting enzymic activation (Lovenberg et al., 1978) and (2) long-term enzyme induction (Costa and Guidotti, 1978; Thoenen and Otten, 1977), operating through sympathetic stimulation by way of the splanchnic nerves. Several stressors and drug treatments cause a transynaptic induction of adrenal TH (Hoeldtke et al., 1974; Joh et al., 1973), associated with an increased in vitro activity (ATHA). We have been interested in delineating the role of central nervous pathways in this induction. Identified central transmitters involved in this process include: (1) inhibitory serotonergic systems (partially localized in the medial raphe nucleus), (2) excitatory dopaminergic (DA) path(s) and (3) excitatory cholinergic path(s) (Lewander et al., 1977; Quik and Sourkes, 1977; Quik et al., 1977). Their effects are ultimately funneled to the adrenals through the splanchnic nerves.
5 citations