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Kumari A, Sreetama S, Mohanakumar KP. Atropine, a muscarinic cholinergic receptor antagonist increases serotonin, but not dopamine levels in discrete brain regions of mice. Neurosci Lett 2007; 423:100-3. [PMID: 17689188 DOI: 10.1016/j.neulet.2007.06.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2007] [Revised: 05/10/2007] [Accepted: 06/19/2007] [Indexed: 01/14/2023]
Abstract
We investigated the effects of atropine, a muscarinic acetylcholine (ACh) receptor antagonist, on the level of serotonin in discrete brain regions, the nucleus raphe dorsalis (NRD), nucleus caudatus putamen (NCP), cerebral cortex and the cerebellum. Biogenic amines were assayed employing HPLC electrochemistry in these regions 30 min following different doses of atropine (5, 10, 25mg/kg; i.p.), and at various time points (15, 30, 60, 120 min) after 25mg/kg of the drug. The cholinergic receptor antagonist caused a dose-dependent alteration in the level of serotonin in NRD, but the increase was not dose-dependent for other regions studied. The metabolite of serotonin, 5-hydroxyindoleacetic acid was unaffected. Atropine did not affect the levels of dopamine or its metabolites dihydroxyphenyl acetic acid and homovanillic acid. The present study suggests significant effect of this antimuscarinic agent on the synthesis of serotonin in the central serotoninergic pathways, which may have clinical relevance.
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Affiliation(s)
- Amrita Kumari
- Laboratory of Clinical & Experimental Neuroscience, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
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Sarkar S, Thomas B, Muralikrishnan D, Mohanakumar KP. Effects of serotoninergic drugs on tremor induced by physostigmine in rats. Behav Brain Res 2000; 109:187-93. [PMID: 10762688 DOI: 10.1016/s0166-4328(99)00171-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We investigated the effects of various serotoninergic drugs and serotonin (5-HT) depletion on physostigmine-induced visible tremor in rats. Physostigmine (0.25-1.5 mg/kg) caused dose-dependent tremor, initiated at 3-5 min (latency decreases as dose increases) and lasted for 30-35 min. Serotonin agonists, 8-hydroxy-2-(di-n-propylamino) tetralin (2.5 mg/kg) and buspirone (5 mg/kg) augmented the tremor response caused by physostigmine. The 5-HT(1)/5-HT(2) receptor antagonist, metergoline (1 mg/kg), and 5-HT(2) blocker, cyproheptadine (10 mg/kg) significantly decreased the duration (40%) as well as intensity (45-50%) of physostigmine-tremor. The 5-HT(2a)/5-HT(2c) antagonist ritanserin (5 mg/kg) significantly reduced the duration (60%) without affecting the intensity of the tremor. In 5-HT depleted rats (p-chlorophenylalanine; 300 mg/kg, for 3 days), physostigmine failed to produce tremor. Interestingly, in these animals, administration of a non-specific 5-HT agonist, 5-methoxy-N,N-dimethyl tryptamine, caused high intensity tremor. These results suggest that presence of 5-HT at the pre-synaptic terminals is needed for the tremor response by physostigmine and the response is greatly mediated via post-synaptic 5-HT receptors. The overall data indicated a direct involvement of central 5-HT system in the cholinergic tremor induced by physostigmine.
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Affiliation(s)
- S Sarkar
- Division of Pharmacology and Experimental Therapeutics, Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Calcutta, India
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3
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Abstract
Animal models of tremor have been widely used in experimental neurology, because they are an indispensable requirement for understanding the pathophysiology of human tremor disorders and the development of new therapeutic agents. This review focuses on three approaches to produce tremor in animals (application of tremorgenic drugs, experimental central nervous system lesions, study of genetic mutants) and their use in simulating tremor syndromes of humans. Whereas harmaline induces a postural/kinetic tremor in animals that shares some features with human essential tremor/enhanced physiological tremor, MPTP tremor is the best model available for rest tremor in people. The tremor following experimental lesion of the ventromedial tegmentum in primates closely resembles Holmes tremor in humans, whereas cerebellar intention tremor is mimicked by cooling of the lateral cerebellar nuclei. The "campus syndrome," discovered in a breed of Pietrain pigs, might be a useful model of human orthostatic tremor. However, no animal model has yet been generated that exactly recreates all features of any of the known tremor disorders in humans. Problems encountered when comparing tremor in animals and humans include differing tremor frequencies and the uncertainty, if specific transmitter abnormalities/central nervous system lesions seen in animal tremor models are characteristic for their human counterparts. The search for adequate tremor models continues.
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Affiliation(s)
- H Wilms
- Klinik für Neurologie 1, Christian-Albrechts-Universität Kiel, Germany
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Stanford JA, Fowler SC. Scopolamine reversal of tremor produced by low doses of physostigmine in rats: evidence for a cholinergic mechanism. Neurosci Lett 1997; 225:157-60. [PMID: 9147394 DOI: 10.1016/s0304-3940(97)00207-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In order to provide evidence for the involvement of cholinergic mechanisms in a low-dose physostigmine-induced tremor, a novel technique for measuring forelimb tremor in rats was used. Rats that were administered physostigmine (0.05 and 0.1 mg/kg, s.c.), scopolamine (0.1 and 0.2 mg/kg, s.c.), and combinations of the two drugs, pressed a force-sensing operandum while a computer measured force output and performed Fourier analyses on resulting force-time waveforms. When given alone, both drugs decreased task engagement but mutually antagonized this effect when given together. Physostigmine increased tremors as well as peak force. Scopolamine decreased tremor and force when administered alone and reversed physostigmine-induced increases in force and tremor. Physostigmine's low-dose induction of increased tremor during rats' skilled forelimb use appears to have a prominent cholinergic component.
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Affiliation(s)
- J A Stanford
- Department of Human Development, University of Kansas, Lawrence 66045, USA
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Bymaster FP, Hemrick-Luecke SK, Perry KW, Fuller RW. Neurochemical evidence for antagonism by olanzapine of dopamine, serotonin, alpha 1-adrenergic and muscarinic receptors in vivo in rats. Psychopharmacology (Berl) 1996; 124:87-94. [PMID: 8935803 DOI: 10.1007/bf02245608] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The ability of the atypical antipsychotic drug candidate olanzapine to antagonize dopamine, serotonin, alpha-adrenergic and muscarinic receptors in vivo was assessed by various neurochemical measurements in rat brain. Olanzapine increased the concentrations of the dopamine metabolites DOPAC and HVA in striatum and nucleus accumbens. Olanzapine antagonized the pergolide-induced decrease of striatal DOPA concentrations in rats treated with gammabutyrolactone and NSD1015 and increased striatal 3-methoxytyramine concentrations in nomifensine-treated rats (but not after gammabutyrolactone administration), suggesting that olanzapine blocked terminal and somatodendritic autoreceptors on dopamine neurons. Inactivation of dopamine D1 and D2 receptors by EEDQ was antagonized by olanzapine. The ex vivo binding of the 5HT2 radioligand [3H]-ketanserin was inhibited by olanzapine treatment, as was quipazine-induced increases in MHPG-SO4, evidence suggesting that olanzapine antagonized 5HT2 receptors. At higher doses, olanzapine increased the concentrations of the norepinephrine metabolite, MHPG-SO4, probably by blocking alpha 1-adrenergic receptors. Olanzapine inhibited ex vivo binding of the muscarinic antagonist radioligand [3H]-pirenzepine and lowered concentrations of striatal, but not hippocampal, acetylcholine levels. The findings provide evidence that olanzapine antagonized dopamine, serotonin, alpha-adrenergic and muscarinic receptors in vivo, consistent with its high affinity for these receptor sites in vitro.
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Affiliation(s)
- F P Bymaster
- Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, IN 46285, USA
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Sethy VH, Heier RF, Moon MW. alpha-Methyl analogues of acetylenic amines as striatal muscarinic antagonists. J Pharm Pharmacol 1991; 43:670-1. [PMID: 1685530 DOI: 10.1111/j.2042-7158.1991.tb03562.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effect of acetylenic amines, with or without alpha-methyl substitution, on striatal acetylcholine (ACh) concentration in rats was investigated. Oxotremorine, oxotremorine-1, and U-77053 (trimethyl (4-(1-pyrrolidinyl)-2 butynyl)-urea), the unsubstituted amines, increased striatal ACh concentration. On the other hand, the corresponding alpha-methyl substituted analogues, alpha-methyl-oxotremorine, BM-5, and alpha-methyl U-77053, decreased the concentration of ACh in the striatum. The results indicate that substitution of alpha-methyl in acetylenic amines converts compounds from agonists to antagonists for striatal muscarinic receptors.
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Affiliation(s)
- V H Sethy
- CNS Research, Upjohn Company, Kalamazoo, MI 49001
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Anderson DR, Harris LW, Lennox WJ, Solana RP. Effects of subacute pretreatment with carbamate together with acute adjunct pretreatment against nerve agent exposure. Drug Chem Toxicol 1991; 14:1-19. [PMID: 1889370 DOI: 10.3109/01480549109017866] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Visual observations were made to compare the pretreatment benefits of subacute (75 micrograms/hr, sc) and acute (146 micrograms/kg, im, at 30 min) deliveries of physostigmine salicylate (Phy) against 2 or 5 LD50s (60 or 150 micrograms/kg, sc) of soman in guinea pigs; scopolamine, 80 micrograms/kg, im, was given routinely at 30 min. In a second set of studies, pretreatment with subacute carbamate [sc, Phy 36 micrograms/hr or pyridostigmine (Pyr), 50 micrograms/hr] and acute adjunct (im, scopolamine, 0.48 mg/kg, or trihexyphenidyl, 2 mg/kg) at 30 min, was used against soman (5 LD50s, sc) and VX (18.4 micrograms/kg, sc; 2 LD50s); atropine (16 mg/kg, im) and 2-PAM (25 mg/kg, im) were given at 1 min post soman. In all studies, lethality, % convulsing, convulsive/subconvulsive score, and recovery time were noted. Subacute dosing for 7 days was done via 14-day osmotic minipumps (OMPs). Results of the first set of studies indicate that subacute and acute deliveries of Phy give essentially comparable protection against 2 or 5 LD50s of soman. The second set of studies show that against soman, the adjuncts scopolamine and trihexyphenidyl when compared, and the carbamates, Phy and Pyr when compared, gave similar protective benefits as indicated by all four monitored measures of toxicity. Phy with either adjunct provided excellent protection against VX induced mortality and convulsions. With both carbamates, trihexyphenidyl gave similar protective benefits against VX. Scopolamine, however, under the conditions used herein, failed to act beneficially with Pyr against VX.
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Affiliation(s)
- D R Anderson
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010-5425
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Sethy VH, Francis JW, Hyslop DK, Patrick Sage G, Oien TT, Meyer AL, Collins RJ, Russell RR, Heier RF, Hoffmann WE, Piercey MF, Nichols NF, Schreur PJD, Moon MW. U-80816: A novel partial muscarinic agonist. Drug Dev Res 1991. [DOI: 10.1002/ddr.430240105] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Harris LW, Talbot BG, Lennox WJ, Anderson DR, Solana RP. Physostigmine (alone and together with adjunct) pretreatment against soman, sarin, tabun and VX intoxication. Drug Chem Toxicol 1991; 14:265-81. [PMID: 1935706 DOI: 10.3109/01480549109002189] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A pretreatment for organophosphorus (OP) anticholinesterase (e.g., soman) intoxication should prevent lethality and convulsions (CNV) at 2 LD50s and be behavioral-decrement-free when given alone. Behavioral-deficit-free pretreatment regimens (PRGs) for guinea pigs consisted of Physostigmine (0.15 mg/kg, im) and adjunct. Adjuncts [mg/kg, im] tested were akineton [0.25], aprophen [8], trihexyphenidyl [2], atropine [16], azaprophen [5], benactyzine [1.25], cogentin [4], dextromethorphan [7.5], ethopropazine [12], kemadrin [1], memantine [5], promethazine [5], scopolamine [0.08] and vontrol [2]. PRGs were given 30 min before soman (60 micrograms/kg, sc; 2 LD50s) or other OP agents. Animals were then observed and graded for signs of intoxication, including CNV at 7 time points and at 24 hr. Physostigmine alone reduced the incidence of CNV and lethality induced by 2 LD50s of soman by 42 and 60%, respectively. All of the PRGs tested abolished lethality and 12 shortened recovery time to 2 hr or less. Also, PRGs including azaprophen or atropine prevented CNV. When selected PRGs were tested against intoxication by sarin, tabun or VX, the efficacy was generally superior to that for soman. The data show that several PRGs are effective against soman intoxication in guinea pigs.
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Affiliation(s)
- L W Harris
- US Army Medical Research Institute of Chemical Defense, Aberdeen Proving Ground, MD 21010-5425
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Mohanakumar KP, Mitra N, Ganguly DK. Tremorogenesis by physostigmine is unrelated to acetylcholinesterase inhibition: evidence for serotoninergic involvement. Neurosci Lett 1990; 120:91-3. [PMID: 2293100 DOI: 10.1016/0304-3940(90)90175-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Studies were performed to bring out a serotoninergic involvement in physostigmine tremor, hitherto known to be working via the cholinergic system. 5-Hydroxytryptamine (5-HT) was estimated fluorimetrically after isolation on Sephadex G-10 and acetylcholinesterase (AChE) was assayed spectrophotometrically. The dose-dependent tremor was quantified by a double-blind study. No correlation (r = 0.01) existed between tremor and AChE inhibition since the non-tremoring dose of physostigmine caused the same degree of enzyme inhibition. An increase of 5-HT was found to be correlated (r = 0.59) with the duration and intensity of tremor. Cholinergic antagonists atropine (2 and 5 mg/kg, i.p.), scopolamine (0.5, 1.0, 2.0 mg/kg, i.p.) and mecamylamine (1 mg/kg, i.p.) failed to block the tremor while the 5-HT antagonists methysergide (5 mg/kg, i.v.) and cyproheptadine (10 and 30 mg/kg, s.c.) could afford more than 60% protection. These results suggest a serotoninergic rather than a cholinergic component in the genesis of physostigmine tremor.
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Affiliation(s)
- K P Mohanakumar
- Division of Pharmacology and Experimental Therapeutics, Indian Institute of Chemical Biology, Calcutta
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Freedman SB, Harley EA, Patel S. Direct measurement of muscarinic agents in the central nervous system of mice using ex vivo binding. Eur J Pharmacol 1989; 174:253-60. [PMID: 2630302 DOI: 10.1016/0014-2999(89)90317-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Muscarinic agents produce a range of side effects including hypothermia and tremor. Although these responses can be used to estimate the in vivo activity of these muscarinic agents in the central nervous system (CNS), the approach is limited by compensatory feedback mechanisms and the difficulty of equating degree of receptor occupancy to effect. We have developed an ex vivo assay to measure the potency and penetration of muscarinic agents into the CNS. The muscarinic antagonists scopolamine and N-methylscopolamine dose dependently inhibited the ex vivo binding of [3H]oxotremorine-M to homogenates of mouse whole brain membranes. Following intraperitoneal administration these compounds had ED50 values of 2.6 and 26 mg/kg respectively, which were comparable to the doses which inhibited RS86 induced hypothermia in mice. Three muscarinic agonists RS86, pilocarpine and arecoline also demonstrated CNS activity in this assay with ED50 values of 11, 23 and 220 mg/kg. RS86 and pilocarpine additionally showed good penetration into the CNS with estimated values of 1.5 and 0.31% of the administered dose. These values were comparable with the ability of these compounds to induce a centrally mediated hypothermic response. These studies demonstrate a simple, quick and reliable biochemical means of assessing a muscarinic agent's potency and penetration within the CNS.
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Affiliation(s)
- S B Freedman
- Merck Sharp and Dohme Research Laboratories, Neuroscience Research Centre, Harlow, Essex, U.K
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Clement JG, Dyck WR. Device for quantitating tremor activity in mice: antitremor activity of atropine versus soman- and oxotremorine-induced tremors. JOURNAL OF PHARMACOLOGICAL METHODS 1989; 22:25-36. [PMID: 2770314 DOI: 10.1016/0160-5402(89)90048-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A tremor monitor was constructed and tested that quantitates soman- and oxotremorine-induced tremors. The device consisted of a force transducer, from which was suspended a plastic beaker containing a mouse. The signal from the force transducer was fed into a tremor monitor, which was essentially a low-pass filter, and quantitated using the Applecounter from Columbus Instruments (Columbus, Ohio) with the data stored on floppy diskette in a personal computer or on a magnetic tape cassette. The tremor monitor demonstrated a dose response relationship to both soman- and oxotremorine-induced tremors and the antagonism of these tremors by various doses of atropine. In addition, the duration of action of a dose of atropine (17.4 mg/kg, ip) normally used in the therapy of organophosphate poisoning was assessed using the atropine antagonism of oxotremorine-induced tremors as an indicator. This device permits the unbiased determination of the tremor activity of a drug and allows the use of statistical analysis on the data produced.
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Affiliation(s)
- J G Clement
- Biomedical Defence Section, Defence Research Establishment Suffield, Ralston, Alberta, Canada
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Stone WS, Cottrill KL, Walker DL, Gold PE. Blood glucose and brain function: interactions with CNS cholinergic systems. BEHAVIORAL AND NEURAL BIOLOGY 1988; 50:325-34. [PMID: 3202815 DOI: 10.1016/s0163-1047(88)91018-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We recently found that glucose injections attenuate amnesia and hyperactivity produced by scopolamine, a muscarinic antagonist. The present study examined whether glucose would augment behavioral effects produced by a muscarinic agonist, physostigmine. In experiment I, doses were first determined for which neither glucose (10 mg/kg) nor physostigmine (0.05 mg/kg) altered scopolamine-induced hyperactivity. However, combined glucose-physostigmine injections significantly reduced scopolamine hyperactivity. Experiment II evaluated the effects of glucose on physostigmine-induced tremors. Glucose (10, 100, and 250 mg/kg) or saline injections were given 20 min before physostigmine injections (0.4 or 0.05 mg/kg). Observations of glucose effects on the severity of physostigmine-induced tremors were then obtained at 5-min intervals for 25 min after physostigmine injections. Glucose (100 mg/kg) significantly facilitated the onset of tremors when injected before either dose of physostigmine, and augmented (at 100 and 250 mg/kg) tremor severity when injected before the lower dose of physostigmine. These findings indicate that glucose can facilitate the actions of a cholinergic agonist on two behaviors, locomotor activity and tremors, adding support to the view that circulating glucose levels can modulate central cholinergic function. More generally, the results provide additional evidence that circulating glucose levels can influence brain function.
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Affiliation(s)
- W S Stone
- Department of Psychology, University of Virginia, Charlottesville 22903
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Abstract
This paper reports the use of an RF capacitance field transducer and spectral analysis to examine the effects of the cholinesterase inhibitor physostigmine on the behavior of unrestrained rats. The technique is shown to permit simultaneous quantification of changes in a variety of motor behaviors. Physostigmine induced a dose-related increase in high-frequency movements and reduced low-frequency movements, but had no effect upon habituation of five to ten Hz movements which occurred with continuous exposure to the testing apparatus.
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Harris L, Stitcher D. Protection against diisopropylfluorophosphate intoxication by pyridostigmine and physostigmine in combination with atropine and mecamylamine. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1984; 327:64-9. [PMID: 6493352 DOI: 10.1007/bf00504993] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Atropine (A), mecamylamine (M), pyridostigmine (Py) and physostigmine (Ph) are pretreatment components of Mix I (A = 0.79, M = 0.79, Py = 0.056 mg/kg) and Mix II (A = 0.79, M = 0.79, Ph = 0.026 mg/kg). They have been successfully used in antagonizing Soman intoxication in experimental animals. Rats were pretreated with either Mix I or Mix II and subsequently exposed to diisopropylfluorphosphate (DFP). Pretreatment with Mix I or Mix II (i.m.) 30 min before DFP (i.v.) protected rats from the lethal effects of DFP. The protective ratios were 2.8 (Mix I) and 6.9 (Mix II). Changes in brain levels of acetylcholine (ACh) were measured to help understand the basis for effectiveness of these pretreatments. In the absence of DFP, pretreatments had no significant (P greater than 0.05) effect on bound or free ACh. Pretreatment did not prevent the DFP-induced rise in bound and free ACh nor the agent-induced physical incapacitation at 30 min post exposure. At 2 h after DFP exposure, rats pretreated with Mix II, but not Mix I, showed significant recovery from signs of physical incapacitation. At 30 min after the administration of 3.3 mg/kg of DFP (i.v.), the levels of free and bound ACh in rats given Mix I or Mix II pretreatment increased above control levels by 705% and 116% and 120% and 43%, respectively. By 2 h after DFP, cerebral ACh levels had changed to 437% and 91% with Mix I pretreatment and 26% and 50% with Mix II pretreatment. These data suggest a correlation between DFP-induced increases in the levels of cerebral ACh, possibly free, and physical incapacitation.(ABSTRACT TRUNCATED AT 250 WORDS)
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Gothóni P, Lehtinen M, Fincke M. Drugs for Parkinson's disease reduce tremor induced by physostigmine. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1983; 323:205-10. [PMID: 6621715 DOI: 10.1007/bf00497664] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The effects of anticholinergic and dopaminergic drugs used for Parkinson's disease were studied on the tremor induced by physostigmine (0.3-3.0 mg/kg) in rats. For the measurement of tremor a new electronic device was employed. Atropine (0.3-1.2 mg/kg) and biperiden (0.01-1.0 mg/kg) reduced the physostigmine-induced tremor in a dose-related manner and could abolish it. Biperiden was less potent than atropine. Methylatropine in a dose of 1.2 mg/kg slightly inhibited the tremor. Amantadine (0.3-3.0 mg/kg) reduced the tremor but only to a certain degree. Bromocriptine (0.1-10.0 mg/kg) reduced it in a manner that was not dose-related. Pimozide potentiated the tremor in the dose of 0.2 mg/kg but not in larger doses. At the onset of the tremor, a small decrease in rectal temperature occurred. The hypothermia lasted significantly longer than the tremor. Neither the anticholinergic nor the dopaminergic anti-Parkinson drugs altered the hypothermic effect of physostigmine. The results show that those anti-Parkinson drugs, which act by increasing the dopaminergic activity can counteract the tremor induced by physostigmine. However, these drugs are clearly less active than th anticholinergic anti-Parkinson drugs.
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Velasco F, Velasco M, Romo R. Effect of carbachol and atropine perfusions in the mesencephalic tegmentum and caudate nucleus on experimental tremor in monkeys. Exp Neurol 1982; 78:450-60. [PMID: 7140907 DOI: 10.1016/0014-4886(82)90062-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Vezzani A, Zatta A, Ladinsky H, Caccia S, Garattini S, Consolo S. Effect of dimethylamino-2-ethoxyimino-2-adamantane (CM 54903), a non-polar dimethylaminoethanol analog, on brain regional cholinergic neurochemical parameters. Biochem Pharmacol 1982; 31:1693-8. [PMID: 7104032 DOI: 10.1016/0006-2952(82)90670-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
CM 54903, a new psychotropic drug with a particular pharmacological profile, produced a widespread but short-lasting decrease in acetylcholine content in rat brain hemispheric regions but not in the midbrain-hindbrain or cerebellum at the dose of 40 mg/kg, i.p. The decrease was most conspicuous in the striatum. Brian regional choline contents were unaltered as were the acetylcholine turnover rates in the striatum and hippocampus. Neither choline acetyltransferase nor acetylcholinesterase activities were altered after the in vitro incubation or the in vivo administration of high amounts of the drug. CM 54903 was found to be a competitive, reversible inhibitor of the sodium-dependent high affinity uptake of choline by crude hippocampal and striatal synaptosomal preparations showing an IC50 of 10 microM in vitro. Despite the fact that the drug readily crosses the blood-brain barrier and achieves brain concentrations several-fold greater than its in vitro IC50, CM 54903 did not inhibit choline uptake in vivo although it was capable of preventing the pentylenetetrazol-stimulated choline uptake by hippocampal synaptosomes. The changes in striatal acetylcholine content induced by the blockade or the stimulation of muscarinic cholinergic receptors or dopaminergic receptors did not interfere with the effect of CM 54903 on striatal acetylcholine content while pentylenetetrazol completely prevented the decrease. The results taken together indicate that the major effect of CM 54903 on the cholinergic neurons is at the presynaptic level to compete with choline at its uptake sites.
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Bohman B, Halaris A, Karbowski M. Effects of tricyclic antidepressants on muscarinic cholinergic receptor binding in mouse brain. Life Sci 1981; 29:833-41. [PMID: 7300578 DOI: 10.1016/0024-3205(81)90040-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Tune L, Coyle JT. Acute extrapyramidal side effects: serum levels of neuroleptics and anticholinergics. Psychopharmacology (Berl) 1981; 75:9-15. [PMID: 6117922 DOI: 10.1007/bf00433493] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
An assay technique for measuring anticholinergic drugs in human serum based upon their inhibition of the specific binding of [3H]-quinuclidinyl benzilate to rat brain muscarinic receptors is described. The assay was validated by demonstrating a close correlation (r = 0.99) between serum levels of nortriptyline measured by the radioenzymatic assay and a GLC technique. The assay measures free anticholinergics, and under standard assay conditions, approximately 95% of benztropine is bound to serum protein. Marked variation in serum anticholinergic levels in patients receiving the same oral dose was observed, and in individual patients there was a non-linear relationship between increasing oral dose and serum anticholinergic levels. In a cross-sectional study of 109 patients receiving concurrently neuroleptics and anticholinergics, there was no correlation (r = 0.029) between serum neuroleptic levels measured by radioreceptor assay and extrapyramidal side effects (EPS). In the patients whose serum anticholinergic levels were also determined, there was a significant inverse correlation (r = 0.44) between anticholinergic levels of EPS. In this cohort of patients, there was no significant correlation between serum anticholinergic and serum neuroleptic levels (r = 0.16) and the ratio of serum anticholinergic to serum neuroleptic was a poor predictor of EPS (r = 0.26). The results suggest a marked variation in sensitivity of patients to the EPS-inducing of neuroleptics; nevertheless, the incidence of EPS decreases with increasing serum levels of anticholinergics. An optimal serum anticholinergic level of 10 pmole atropine equivalent per ml was associated with a low incidence of EPS and is relevant to drug action at the striatal muscarinic receptor.
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Abstract
A simple and accurate device for recording tremor intensity in unanaesthetized and unrestrained rats is described. The physical measures of tremor are shown to have several advantages over previous devices. First, the new apparatus, unlike some earlier ones, does not restrict the animal's movements to an unusually small cage, with weighty mechanical devices or with electrical leads. Second, most earlier methods for measuring tremor use a subjective rating scale. However, the present method uses objective and reliable measures. In a double-blind, illustrative experiment involving complete crossover, Wistar rats were randomly injected IP with physostigmine in doses of 0.2, 0.4, 0.6 and 0.8 mg/kg or the corresponding amount of 0.9% NaCl solution as control. The recorded tremor intensity showed a clear dose-response relationship for physostigmine. Moreover, linear regression of the dose-response relationship showed that tremor intensity increased linearly with increasing doses of physostigmine. The cholinergic antagonist atropine (0.3 mg/kg SC) antagonized physostigmine-induced tremor, whereas methylatropine (0.3 mg/kg SC) tended to potentiate it. These results show that the technique described is suitable for quantification of tremor intensity in rats and for testing drug interactions on physostigmine-induced tremor.
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Harris LW, Stitcher DL, Heyl WC. The effects of pretreatments with carbamates, atropine and mecamylamine on survival and on soman-induced alterations in rat and rabbit brain acetylcholine. Life Sci 1980; 26:1885-91. [PMID: 7401906 DOI: 10.1016/0024-3205(80)90617-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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24
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Lassen JB. Inhibition of apomorphine-induced climbing in mice by cholinergic drugs and neuroleptics. ACTA PHARMACOLOGICA ET TOXICOLOGICA 1979; 45:161-5. [PMID: 40391 DOI: 10.1111/j.1600-0773.1979.tb02376.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Apomorphine (ap) was administered subcutaneously to mice kept in individual cages. Ap elicited an abnormal vertical climbing behaviour. The muscarinomimetics physostigmine and oxotremorine as well as the neuroleptics clozapine and haloperidol inhibited the climbing produced by ap 1 mg/kg. A small inactive dose of physostigmine potentiated the effect of clozapine but not that of haloperidol. The anticholinergic atropine antagonized the effect of physostigmine, oxotremozine, clozapine and haloperidol. The climbing behaviour produced by ap is presumably due to stimulation of dopamine receptors and this effect can be antagonized either by blockade of dopamine receptors or by activation of muscarinic receptors. Some lines of evidence suggest that the ap-inhibitory effect of clozapine may be partly due to a muscarinomimetic effect.
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Wecker L, Dettbarn WD. Relationship between choline availability and acetylcholine synthesis in discrete regions of rat brain. J Neurochem 1979; 32:961-7. [PMID: 430073 DOI: 10.1111/j.1471-4159.1979.tb04581.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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26
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Harris LW, Heyl WC, Stitcher DL, Moore RD. Effect of atropine and/or physostigmine on cerebral acetylcholine in rats poisoned with soman. Life Sci 1978; 22:907-10. [PMID: 642705 DOI: 10.1016/0024-3205(78)90615-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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27
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Maayani S, Egozi Y, Pinchasi I, Sokolovsky M. On the interaction of drugs with the cholinergic nervous system--V. Characterization of some effects induced by physostigmine in mice: in vivo and in vitro studies. Biochem Pharmacol 1978; 27:203-11. [PMID: 623676 DOI: 10.1016/0006-2952(78)90302-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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28
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Stitcher DL, Harris LW, Heyl WC, Alter SC. Effects of pyridostigmine and cholinolytics on cholinesterase and acetylcholine in Soman poisoned rats. Drug Chem Toxicol 1978; 1:355-62. [PMID: 755675 DOI: 10.3109/01480547809016047] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Soman reduced blood and brain cholinesterase (ChE) activity to less than 15% and increased cerebral acetylcholine (ACh) levels to 137.4% of control. When pyridostigmine (P) was used as a prophylactic adjunct, it reduced blood ChE activity to 31.6% of control, failed to significantly alter brain ChE activity, and protected more than 70% of the blood (but not brain enzyme) from phosphonylation by soman. Benactyzine (B) was more effective than atropine (A) in reducing cerebral ACh concentrations, while a combination of the two was more effective than either alone. A prophylaxis of P + A + B was effective in controlling ACh levels in rats poisoned with one LD50 dose of Soman. Since P did not diminish the effects of the cholinolytics on cerebral ACh, this (together with the enzyme data) suggests that the two cholinolytics alone provided the central protection.
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29
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Does histamine interact with cholinergic neurones in its cataleptogenic action in the rat? Neuropharmacology 1977. [DOI: 10.1016/0028-3908(77)90146-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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30
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Egbe PC, Wray SR. Differential attenuation by atropine and d-amphetamine on hyperactivity: possible clinical implications. Psychopharmacology (Berl) 1977; 54:25-30. [PMID: 410057 DOI: 10.1007/bf00426536] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Intraperitoneal administration of physostigmine (0.025 to 0.18 mg/kg) to rats resulted in significant increases in motor activity as measured with jiggle platforms. Doses of physostigmine 0.2 mg/kg or more decreased motor activity. The physostigmine-induced hyperactivity was attenuated by atropine (5 mg/kg) given before or after physostigmine (0.05 mg/kg). On the contrary, d-amphetamine (2 mg/kg), given before or after, significantly potentiated the physostigmine-induced increase in motor activity. The relevance of the cholinergic system in mediating hyperactive behaviour in children is discussed.
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31
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Guyenet PG, Javoy F, Euvrard C, Glowinski J. The effect of drugs on the choline and acetylcholine content of the rat striatum following two methods of sacrifice. Neuropharmacology 1977; 16:385-90. [PMID: 904768 DOI: 10.1016/0028-3908(77)90078-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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32
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Nordberg A, Sundwall A. Effect of oxotremorine on endogenous acetylcholine and on uptake and biotransformation of radioactive choline in discrete regions of mouse brain in vivo. Biochem Pharmacol 1976; 25:135-40. [PMID: 1259775 DOI: 10.1016/0006-2952(76)90280-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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33
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Silbergeld EK, Goldberg AM. Pharmacological and neurochemical investigations of lead-induced hyperactivity. Neuropharmacology 1975; 14:431-44. [PMID: 1171389 DOI: 10.1016/0028-3908(75)90026-x] [Citation(s) in RCA: 133] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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34
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Paalzow G, Paalzow L. Antinociceptive action of oxotremorine and regional turnover of rat brain noradrenaline, dopamine and 5-HT. Eur J Pharmacol 1975; 31:261-72. [PMID: 238855 DOI: 10.1016/0014-2999(75)90048-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In the rat, oxotremorine increases the threshold for vocalisation after-discharge (affective component of pain reactions) dose dependently at subtremor doses (30-67 mug/kg s.c.). Doses of 225-506 mug/kg were needed to elevate the thresholds for vocalisation and motor response. 1-Tryptophan, PCPA, alpha-methyl-p-tyrosine, 1-Dopa, pimozide and LSD-25 did not affect the antinociceptive activity of oxotremorine, while phenocybenzamine slightly increased the threshold for vocalisation. Oxotremorine did not change the endogenous brain concentrations of noradrenaline and dopamine or 5-HT but decreased that of 5-HIAA in all brain regions at the time of maximal analgesia. The decrease of 5-HIAA was still present after pretreatment with probenecid. After inhibition of tyrosine hydroxylase, oxotremorine accelerated the depletion of dopamine in telencephalic cortex during maximal antinociceptive activity and of noradrenaline in all brain regions at a time when this activity had vanished. Atropine significantly antagonized the analgesic activity of oxotremorine. It is concluded that oxotremorine antinociceptive activity in the rat is related to a cholinergic compoent, while a monoaminergic component is not directly involved.
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Rommelspacher H, Kuhar MJ. Effects of dopaminergic drugs and acute medial forebrain bundle lesions on striatal acetylcholine levels. Life Sci 1975; 16:65-70. [PMID: 234165 DOI: 10.1016/0024-3205(75)90209-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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36
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Rommelspacher H, Kuhar MJ. Effects of drugs and axotomy on acetylcholine levels in central cholinergic neurons. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1975; 291:17-21. [PMID: 172807 DOI: 10.1007/bf00510817] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Administration of cholinergic nuscarinic agonists either did not alter, or increased hippocampal Ach levels, while antagonists lowered the levels. As observed previously, placement of lesions in the medial septal area resulted in a rise in hippocampal Ach levels in the first thirty minutes. Agonist drugs administered immediately before lesion, further increased the post-lesion rise in Ach levels. With antagonists, inconsistent results were obtained in that atropine blocked the post-lesion rise, while scopolamine and quinuclidinyl benzilate (QNB) potentiated the post-lesion rise. These results suggest that there may be receptor-mediated effects on Ach synthesis or release after axotomy.
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37
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Sethy VH, Van Woert MH. Regulation of striatal acetylcholine concentration by dopamine receptors. Nature 1974; 251:529-30. [PMID: 4421728 DOI: 10.1038/251529a0] [Citation(s) in RCA: 103] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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38
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Sethy VH, Van Woert MH. Brain acetylcholine and cholinesterase: effect of phenothiazines and physostigmine interaction in rats. J Neurochem 1974; 23:105-9. [PMID: 4850818 DOI: 10.1111/j.1471-4159.1974.tb06922.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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39
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Svenneby G, Roberts E. Elevated acetylcholine contents in mouse brain after treatment with bicuculline and picrotoxin. J Neurochem 1974; 23:275-7. [PMID: 4152870 DOI: 10.1111/j.1471-4159.1974.tb06947.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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40
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Consolo S, Ladinsky H, Garattini S. Effect of several dopaminergic drugs and trihexyphenidyl on cholinergic parameters in the rat striatum. J Pharm Pharmacol 1974; 26:275-7. [PMID: 4151386 DOI: 10.1111/j.2042-7158.1974.tb09272.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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41
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Kilbinger H, Krieglstein J. Applicability of the isolated perfused rat brain for studying central cholinergic mechanisms. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1974; 285:407-11. [PMID: 4280524 DOI: 10.1007/bf00501469] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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