Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Research was conducted upon 28 patients with a diagnosis of endogenous depression after their pharmacological treatment with imipramine or chlorimipramine. The investigation considered the interrelationship between psychophysiological parameters (heart rate, respiration rhythm, postural muscular tension) and the indices of the cholinergic and adrenergic systems (kinetic parameters of choline transport in the blood; Vmax, the activity of plasmic pseudocholinesterase, Che; blood acetylcholinesterase AChE, monoaminoxidase in blood platelets, MAO; and dopamine beta hydroxylase DBH). The results indicate that during relapse of endogenous depression there occurs an imbalance in the cholinergic-adrenergic systems which may be the result of some somatic symptoms typically found in the depression syndrome. The appearance, after pharmacotherapy, of a correlation between the indices of the activity of the cholinergic system with the respiratory rhythm suggest that the part played by the cholinergic mechanism in the regulation of autonomic processes normalizes itself during the course of successful therapy. The appearance of characteristic correlations between the activity of the cholinergic and adrenergic systems and the psychophysiological parameters in the presence of relatively low psychological stress seems to accompany successful treatment with imipramine and chlorimipramine.
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PMID:[Psychophysiological characteristics and metabolic indices of neurotransmitter metabolism in patients ill with endogenous depression]. 130 98

The ability of acetylcholinesterase from fetal bovine serum (FBS AChE) to protect against soman, a highly toxic organophosphorus (OP) compound, was tested in rhesus monkeys. Intravenous administration of FBS AChE produced a minimal behavioral effect on the serial probe recognition task, a sensitive test of cognitive function and short-term memory. Pharmacokinetic studies of injected FBS AChE indicated a plasma half-life of 40 hr for FBS AChE in monkeys. Both in vitro and in vivo titration of FBS AChE with soman produced a 1:1 stoichiometry between organophosphate-inhibited FBS AChE and the cumulative dose of the toxic stereoisomers of soman. Administration of FBS AChE protected monkeys against the lethal effects of up to 2.7 LD50 of soman and prevented any signs of organophosphate intoxication, e.g., excessive secretions, respiratory depression, muscle fasciculations, or convulsions. In addition, monkeys pretreated with FBS AChE were devoid of any behavioral incapacitation after soman challenge, as measured by the serial probe recognition task. Compared to the current multicomponent drug treatment against soman, which does not prevent the signs or the behavioral deficits resulting from OP intoxication, use of FBS AChE as a single pretreatment drug provides significantly effective protection against both the lethal and the behavioral effects of soman.
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PMID:Protection of rhesus monkeys against soman and prevention of performance decrement by pretreatment with acetylcholinesterase. 163 92

There are at least five mechanisms by which the central nervous system regulates neural and humoral systems that control the blood pressure (BP). Particular attention has been paid to central cholinergic-adrenergic interactions in the regulation of BP. Physostigmine and other anticholinesterases which penetrate the blood-brain barrier, both carbamates and organophosphates, produce an increase of BP. This effect can be abolished by atropine, but not by methylatropine. The available evidence indicates that physostigmine and other AChE inhibitors initially produce an activation of central muscarinic receptors, which subsequently leads to an increase of the peripheral adrenergic activity. The hypertensive response to physostigmine is possible only if a functionally competent ChE is present in the brain. This effect of physostigmine is regularly associated with a dose-related increase in the neural activity in the preganglionic fibers of the cervical sympathetic nerve. BP rise after physostigmine is significantly less in immunosympathectomized animals and almost completely abolished after chemical sympathectomy. Physostigmine significantly increased the plasma concentration of catecholamines. After electrocoagulation of the locus coeruleus, not only did a significant decrease occur in the basic level of noradrenaline in plasma, but there was also a strong depression of the noradrenaline plasma response to physostigmine and immobilization. Physostigmine increased lipolysis and glycogenolysis, whereas neostigmine did not produce any change. Several directly acting cholinergic agonists alter the functions of the cardiovascular system when injected directly into the cerebral ventricular system, or directly into various brain regions. The most probable sites of action of AChE inhibitors and directly acting cholinergic agonists are the locus coeruleus, the nucleus tractus solitarii and the rostral ventrolateral medulla (RVLM). The primary activation of the cholinergic synapse is believed to take place in RVLM. Met-enkephalin, Leu-enkephalin and beta-endorphin, when applied exogenously, depress or even abolish the hypertensive effect of physostigmine. The same type of response was obtained after application of substances which inhibit the enkephalin-degrading enzymes (bestatin, phosphoramidon). Thus, the exogenous or endogenous enkephalins activate the opioid receptors in the brain and at the same time produce a depression of the cholinergic-adrenergic interaction in the central nervous system, which is a prerequisite for the hypertensive response to physostigmine. The functional role of the central cholinergic mechanisms in BP control under physiological conditions has not been established with certainty. These mechanisms might have a more significant role under pathological or homeostatic disturbances. For example, physostigmine showed a life-saving effect in acute hypovolemic shock in rabbits.
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PMID:Transmitter interactions in the central cholinergic control of blood pressure regulation. 168 40

This study compared the effects of 3 novel antiAChE agents (derivatives of dimethylaminoethyl-phenyl carbamate) with that of physostigmine on the respiratory depression induced by morphine in rabbits. Each drug, RA6, (1 mg i.v., 2 mg s.c.) RA7 (1 or 2 mg i.v.); RA15 (0.25 or 0.5 mg i.v.), physostigmine (0.05 or 0.1 mg i.v.) or saline (1 ml), was injected simultaneously with morphine (8 mg i.v.) to groups of 6-10 rabbits. Respiration rate, blood gases and pH were monitored for 3 hr. Plasma ChE was measured before and at 15 min intervals after injection. The 4 antiAChE's were given to 40 other rabbits, which were sacrificed at the time of maximal antagonism of the respiratory depressant effect of morphine, in order to measure the activity of AChE in the medulla, cortex and hippocampus. Physostigmine (0.1 mg) only antagonized the increase in paCO2 induced by morphine at 15 and 30 min. The drugs RA15 (0.5 mg), RA6 (2.5 mg) and RA7 (2 mg) almost completely prevented the respiratory depression, without obvious signs of peripheral cholinergic hyperactivity, for at least 3 hr. There was no relationship between the degree of antagonism of the effects of morphine with any drug and that of inhibition of ChE in plasma. In contrast, a highly significant correlation (P less than 0.01) was found between the former and the amount of inhibition of AChE in the medulla. It is suggested that the novel carbamates may have potential therapeutic application in reducing the respiratory depression of opiates, without impairing analgesia.
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PMID:Antagonism of morphine-induced respiratory depression by novel anticholinesterase agents. 175 86

Before the onset of bovine paresis a stage of hyperactivity and hypersensitivity was observed in clinical as well as in immunologically provoked cases. By gas chromatographic analysis of choline (Ch) in plasma and serum from four immunologically provoked cows this stage was verified to be an initial immuno-cholinergic hyperactivation. In the first hour after antigen challenge with 0.5 mg nematode AChE there was a very sharp rise in Ch mainly from agonist-stimulated and phospholipase mediated phosphatidylcholine (PC) breakdown. A secondary massive influx of Ca into cells was mirrored in a 1 mmol/l depression of serum-Ca values during the first hours. The hyperagonism mediated Ca-translocation brought water into cells, resulting in reduced plasma volume. The generally supposed mechanism of secondary, Ca-mediated cell damage and cell death was initiated and sometimes resulted in "Downers" with persisting paralysis. All acetylcholine (ACh)-stimulated parts from CNS to the periphery are irregularly involved explaining the very varied clinical appearance of bovine paresis, and the influence on for instance the autonomous nerve system, adrenals and pancreas. In the experimental group, ACh in plasma showed a sharp fall within the first hour, while there were fairly constant values of serum-ACh in the first four hours, possibly indicating some antibody protection. When paresis was established between 15-28 hours after challenge the general anergetic state was characterised by low ACh-levels. Also in a larger field group ACh-levels were significantly depressed in paretic compared to healthy cows. The unexpected finding in this group was considerably higher levels of ACh and especially Ch in serum compared to plasma. The origin of ACh and Ch had to be blood cells. Preliminary gas chromatographic analysis has confirmed ACh-synthesis by leucocytes and an integrated immuno-cholinergic system of great importance can be anticipated. The general feature of bovine paresis is updated by immune-etiological, pathophysiological, blood chemical, clinical-experimental and nomenclature considerations. The exact mechanism of pathogenesis is not revealed in this investigation, though many circumstances favour an anti-Id mediated hyperagonism. Other types of investigations and above all more basic knowledge of distribution and functional character of cholinergic components on immune cells are required.
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PMID:Origin and significance of acetylcholine and choline in plasma and serum from normal and paretic cows. 179 76

The present study demonstrates that the reversible and irreversible anti-ChE agents have direct actions on the nicotinic acetylcholine receptor-ionic channel (AChR) and on the locust glutamatergic neuromuscular junction. In addition, the prophylaxis of lethality of organophosphorus anti-ChE compounds was studied. The lethality of VX and sarin was diminished when the rats were pretreated with physostigmine and atropine. The effectiveness of this protection, however, was markedly increased when a ganglionic blocker, either mecamylamine or chlorisondamine, was added, such that all the animals survived after receiving four times a lethal dose of VX. Pretreated animals receiving sarin showed significant recovery of morphological and functional properties of the neuromuscular junction as compared to the damage of structures from animals without pretreatment. Blood ChE inhibition was slightly decreased while brain and muscle AChE levels were significantly recovered (from 98 and 70% to 56 and 32%, respectively) by the pretreatment. This effect may partially explain the protection given by physostigmine but not that afforded by addition of a non-anti-ChE agent. Physostigmine, at concentrations greater than 20 microM, showed both a marked depression of the peak amplitudes of the endplate current (EPC) and a shortening of the decay time constants tau EPC. These effects were mostly due to a direct drug interaction with the nicotinic AChR blocking the ionic channel in its open conformation. Single-channel recordings showed that physostigmine decreases conductance and open times of the channels activated in the presence of ACh and in addition has an agonistic property on the nicotinic AChR. VX, on the other hand, only shortened the open times of ACh-activated channels without affecting the conductance. No agonist property was detected with VX. On glutamatergic synapses, the ChE inhibitors generated spontaneous firing of end-plate potentials (EPPs) and action potentials (APs). This effect was blocked in the presence of low external Ca2+ concentration or tetrodotoxin. It seems that the spontaneous EPP and AP firing resulted from an increased transmitter release induced by an increase in Na+ influx at the presynpatic nerve terminal. Physostigmine and some irreversible ChE inhibitors (VX and DFP) also blocked the postjunctional glutamate receptors. Similar to the nicotinic AChR, this effect was mostly related to a blockade of the open channels. In conclusion, the present studies showed significant protection of rats by physostigmine in combination with some ganglionic antagonists against lethality by organophosphate agents.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Multiple actions of anticholinesterase agents on chemosensitive synapses: molecular basis for prophylaxis and treatment of organophosphate poisoning. 286 60

During chronic intoxication by diisopropyl fluorophosphate (Isoflurophate, DFP; s.c. treatment on alternate days - first dose of 1.1 mg/kg, subsequent doses of 0.7 mg/kg each until the 23rd day) a partial recovery of enzymatic activity was found at 24 h after each DFP administration. Relative to maximal AChE depression at 90 min, these rises were more pronounced in the soluble portion of the enzyme than in total enzyme preparation, i.e., that containing mainly membrane-bound AChE. Moreover, from the 2nd DFP administration on, there was a persistent increase of medium-molecular-weight forms both in soluble and in total AChE. The results suggest an important role of the soluble portion of AChE and of medium forms in the process of recovery of enzymatic activity.
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PMID:Mechanisms of recovery of brain acetylcholinesterase in rats during chronic intoxication by isoflurophate. 695 89

The effects of acute administration of diisopropyl fluorophosphate, Isofluorophate (DFP) 1.1 mg/kg SC on soluble brain acetylcholinesterase were studied in male Sprague-Dawley rats sacrificed at time intervals ranging from 3 hr to 25 days. Three main molecular forms of AChE were separated by polyacrylamide gel electrophoresis followed by enzymatic reaction with acetylthiocholine, staining and scanning densitometry for their quantitative evaluation. In some experiments the same three forms were separated by chromatography-gel filtration. In the brain of untreated animals the slowly-, medium- and fast-migrating forms accounted respectively for 64, 18 and 18% of the soluble AChE activity. At 3 hr after treatment with DFP, resulting in an 80% reduction of soluble AChE, the relative contribution of slowly-migrating forms to the residual enzymatic activity was decreased, while that of medium-forms was significantly increased. These changes became gradually more pronounced and reached their maximum at 4 days, when AChE had recovered to about 50% of control level. Subsequently, the distribution of the molecular forms showed a progressive return toward the control pattern. The partial recovery in the initial period after maximal enzyme depression was mainly due to an increase of medium-migrating forms. Thus these may be precursors of the biosynthesis of slowly-migrating forms and/or there may be functional specialization of different forms.
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PMID:Molecular forms of rat brain acetylcholinesterase in DFP intoxication and subsequent recovery. 729 Feb 86

In the course of investigating a large number of non-demented subjects, a 68 year old female dying of coronary artery disease was found to have Pick bodies in her grossly normal brain. Although only mild subcortical gliosis and no neuron loss were observed. Pick bodies were found throughout the brain and occasional balloon cells were noted. Pick bodies and numerous neurons were also ALZ-50 and Tau-1 immunoreactive. Retrospective studies indicated a lack of overt intellectual decline or depression in this individual. Frontal, temporal and occipital poles, amygdala, hypothalamus and nucleus basalis of Meynert (nbM) were analyzed for ChAT, AChE and MAO-A and -B enzymatic activities and for the binding of 5HT and imipramine. Cholinergic decreases were found only in subcortical structures. Serotonin binding decreases were widespread, excluding the nbM. Altered MAO-B activity was regionally variable, and no differences in MAO-A activity or imipramine binding were observed. Few differences in neurochemical alterations were observed in the current non-demented subject with abundant Pick bodies compared to previous studies of demented Pick's patients. This case strongly suggests that chemical dysfunction and neuropathological features of Pick's disease occur in advance of overt clinical manifestations of the disorder.
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PMID:Neurochemical and histopathologic alterations characteristic of Pick's disease in a non-demented individual. 830 18

We have investigated the role of the projection from the magnocellular basal forebrain to the olfactory bulb in regulating synaptic transmission in the commissural connection between the two olfactory bulbs. Commissural fibers arise in the contralateral anterior olfactory nucleus, travel in the anterior wing of the anterior commissure (AC), and terminate in the granule cell layer of the olfactory bulb. Electrical stimulation of the commissure causes synaptic activation of granule cells in the granule cell layer of the bulb; the resulting field potential is a reliable indicator of this synaptic current. Microinjections of cholinergic agonists, but not of identical, or larger, quantities of vehicle, reduced the amplitude of this AC field potential. Systemic injection of scopolamine reversed this depression and returned the AC response amplitude to control levels. Irreversible AChE inhibition also reduced the amplitude of the AC response, and muscarinic blockade reversed this effect. Cholinergic terminals in the olfactory bulb arise entirely from the axons of magnocellular basal forebrain neurons in the nucleus of the diagonal band (NDB). Electrical stimulation of NDB, which should release ACh, as well as other transmitters, depressed the AC response. Brief trains of NDB shocks caused a moderate decrease in the AC response that lasted 1-2 sec. Longer shock trains, which caused marked potentiation of the NDB field potential, caused a profound, prolonged (> 20 sec) inhibition of the AC response. Antidromic tests demonstrated that NDB stimulation significantly decreased the excitability of AC terminals. This and other characteristics of the inhibition strongly suggest that the decrease in amplitude of the field potential response to AC stimulation caused by cholinergic agonists and stimulation of NDB is due to presynaptic inhibition leading to reduced release of transmitter from AC terminals. These results suggest that one function of the basal forebrain projection to the olfactory bulb is inhibition of the commissural connection between the two olfactory bulbs. As NDB has been implicated in theta pacemaker input to the olfactory bulb, phasic NDB inhibition of centrifugal afferents to the bulb could function to coordinate signal processing temporally in the olfactory system. Temporal coordination may be particularly important to olfactory circuit function, as this system lacks the point-to-point topographical organization characteristic of other sensory systems.
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PMID:Evidence for presynaptic inhibition of the olfactory commissural pathway by cholinergic agonists and stimulation of the nucleus of the diagonal band. 842 31


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