Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “SCOPOLAMINE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 883 records · Page 49Linked to original sources
PubMed1997

Scopolamine reversal of tremor produced by low doses of physostigmine in rats: evidence for a cholinergic mechanism.

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.

Animals↗
PubMed1999

Scopolamine enhances middle-latency auditory evoked magnetic fields.

To study the influence of central cholinergic muscarinic transmission on human cortical middle-latency auditory evoked magnetic fields (MAEF), centrally acting antagonist scopolamine hydrobromide (0.3 mg, i.v.), and peripheral muscarinic receptor antagonist glycopyrrolate (0.2 mg, i.v.), were administered to 13 healthy subjects in a double-blind randomized cross-over design. MAEF, measured with whole-head magnetoencephalography (MEG), were elicited with clicks applied at 10-Hz rate to the left ear. The amplitudes of N(b)m and P(a)m responses were augmented by scopolamine (P < 0.01 and P < 0.08). These effects were about equally strong for responses from ipsi- and contralateral auditory cortices. Thus, the present MEG findings revealed specific modulation of cortical generators of middle-latency auditory evoked responses by muscarinic transmission. These findings might be associated with auditory processing deficits observed in dementias with cholinergic disturbances.

Acetylcholine↗
PubMed1999

Scopolamine-sensitive and resistant components of increase in cerebral cortical blood flow elicited by periaqueductal gray matter of rats.

The present study attempted to evaluate the effects of inhibition of cortical muscarinic receptors on the increase in cortical blood flow (laser-Doppler flowmetry) elicited by chemical stimulation of the periaqueductal gray matter in 28 anesthetized rats with cervical cordotomy. A new device was introduced which allowed focal cortical superfusion with scopolamine, an antagonist for muscarinic receptors, without disturbing the temperature of an exposed cortical area under study. We found that although the flow increase was attenuated by scopolamine (31.6 micromol/l to 1 mmol/l) so applied, about one third of it was resistant to the treatment. Cortical muscarinic and non-muscarinic receptor mechanisms may thus subserve the mediation of the flow increase.

Animals↗
PubMed1999

Scopolamine augments transient auditory 40-hz magnetic response in humans.

The influence of neocortical muscarinic transmission on auditory-evoked 40-Hz magnetic response was studied in 13 healthy subjects in a double-blind randomized cross-over design. Either a centrally (scopolamine hydrobromide, 0.3 mg, i.v.) or a peripherally (glycopyrrolate, 0.2 mg, i.v.) acting antagonist of muscarinic transmission was administered during two sessions of magnetoencephalographic recording of 40-Hz response elicited by monaural tones. Scopolamine significantly (P < 0.01) augmented the 40-Hz magnetic response over the hemispheres ipsi- and contralateral to the ear stimulated. This finding suggests muscarinic modulation of the auditory evoked transient 40-Hz response.

Adult↗
PubMed1999

Korean red ginseng saponins with low ratios of protopanaxadiol and protopanaxatriol saponin improve scopolamine-induced learning disability and spatial working memory in mice.

The effects of two ginseng saponins having a different ratio of protopanaxadiol (PD) and protopanaxatriol saponins (PT) on the learning impairment induced by scopolamine, and learning and memory in mice were investigated in a passive avoidance task and a Morris water maze task. The ratio of PD and PT was 1.24 and 1.46, respectively. Before training, the ginseng saponins were administered intraperitoneally at doses of 50 and 100 mg/kg. The two saponins improved the scopolamine-induced learning impairment at different dosages in mice, 50 and 100 mg/kg, respectively. However, the two saponins did not show a favorable effect on learning and memory in normal mice. Korean red ginseng saponin with a low PD/PT ratio had an improving effect on spatial working memory, but the saponin with a high PD/PT ratio did not. This finding suggests that the PD/PT ratio of the ginseng saponins may be an important factor in the pharmacological role of red ginseng as a medicinal herb.

Animals↗
PubMed2003

Decursin from Angelica gigas mitigates amnesia induced by scopolamine in mice.

We previously reported that a total methanolic extract of the underground part of Angelica gigas Nakai (Umbelliferae) (here-in-after abbreviated AG) significantly inhibited acetylcholinesterase (AChE) activity. We characterized 12 coumarin derivatives including both decursin and decursinol from extracts of AG. In this study, we evaluated the anti-amnestic activity of decursin, a major coumarin constituent isolated from AG, in vivo using ICR mice with amnesia induced by scopolamine (1 mg/kg body weight, s.c.). Decursin, when administered to mice at 1 and 5 mg/kg body weight i.p., significantly ameliorated scopolamine-induced amnesia as measured in both the passive avoidance test and the Morris water maze test. Moreover, decursin significantly inhibited AChE activity by 34% in the hippocampus of treated mice. These results indicate that decursin may exert anti-amnestic activity in vivo through inhibition of AChE activity in the hippocampus.

Acetylcholinesterase↗
PubMed1991

Scopolamine- and morphine-induced impairments of spontaneous alternation performance in mice: reversal with glucose and with cholinergic and adrenergic agonists.

Administration of epinephrine and glucose, as well as drugs that influence cholinergic and opiate systems, can enhance or impair memory. The present experiments examined the possibility that peripheral glucose administration might reverse scopolamine- and morphine-induced impairments in a spontaneous alternation task. Mice received all drug administrations 30 min before testing. Scopolamine-induced (3 mg/kg) deficits in alternation performance were reversed by glucose (100 and 250 mg/kg), amphetamine (1 mg/kg), epinephrine, physostigmine, and oxotremorine (each 0.1 mg/kg). Morphine (10 mg/kg) also impaired spontaneous alternation performance, and glucose (100 and 300 mg/kg) reversed this impairment as well. These findings are consistent with the view that central cholinergic systems, possibly under inhibitory opiate regulation, may contribute to glucose and epinephrine effects on memory storage.

Amphetamine↗
PubMed1993

Disruption of human eyeblink conditioning after central cholinergic blockade with scopolamine.

Human (Homo sapiens) volunteers (N = 72) received saline, a low dose of oral scopolamine (0.6 mg), a high dose of oral scopolamine (1.2 mg), or a peripheral analogue (glycopyrrolate). They then underwent classical conditioning of the eyeblink response to a tone conditioned stimulus (CS) and a corneal airpuff unconditioned stimulus (UCS) in a delay conditioning paradigm. There was a dose-related decline in acquisition of the conditioned response. These drug-induced conditioning deficits were similar to those previously reported in rabbit eyeblink conditioning and could not be attributed to such nonassociative factors as changes in auditory thresholds to the tone CS, magnitude of reflexive blinks to the airpuff UCS, or to changes in spontaneous blink rates.

Administration, Oral↗
PubMed1994

Scopolamine injection into the olfactory bulb impairs short-term olfactory memory in rats.

A previous experiment showed that systemic administration of the muscarinic antagonist scopolamine altered delayed matching in an olfactory task in rats. The present experiment tested whether the impairment could result from blockade of the cholinergic transmission in the first relay structure of the olfactory system, the olfactory bulb. Drug was infused directly into both olfactory bulbs before test sessions. Results showed that the intrabulbar infusion reproduced the effect of the systemic administration. With a 4-s delay between target odor and choice test, performances of treated rats remained unchanged; but with a 30-s delay, rats performed randomly. Results from a complementary electrophysiological experiment in anesthetized rats support the idea that scopolamine injected into the olfactory bulb was unlikely to have reached more central structures. Further evidence for the involvement of pure sensory areas in short-term memory is concluded.

Animals↗
PubMed2000

Medial septal microinfusion of scopolamine disrupts hippocampal activity and trace jaw movement conditioning.

This study investigated the effects of microinfusion of scopolamine into the medial septum (MS Scp) on hippocampal neurophysiology and learning of the rabbit's classically conditioned jaw movement response. The percentage of hippocampal theta slow waves (2-8 Hz) decreased after drug infusion in the MS Scp group but did not change in control groups that received infusion of saline into the MS or scopolamine into the cortex. Unit recordings from the MS Scp group showed significantly smaller conditioning-related hippocampal neural responses than seen in controls, and during conditioning, rabbits in the MS Scp group took significantly longer to reach learning criterion than either control group. Thus, the neural and behavioral impairments previously reported for systemic muscarinic blockade were reproduced by microinfusions restricted to the medial septal nucleus.

Animals↗
PubMed2002

Posttraining intra-basolateral amygdala scopolamine impairs food- and amphetamine-induced conditioned place preferences.

The present study investigated the role of cholinergic muscarinic receptor function within the basolateral amygdala memory in the consolidation of conditioned place preference (CPP) memory. Adult male Long-Evans rats were confined to treatment- or nontreatment-paired compartments for 30 min on 4 alternating days. After training, rats received intrabasolateral amygdala infusions of scopolamine (2.5 microg or 5.0 microg/0.5 microl) or saline. The rats were then given a 20-min test session, and the time spent in each of the compartments was recorded. Immediate posttraining (but not delayed 2 hr) scopolamine (5.0 microg) blocked acquisition of food- and amphetamine-induced CPPs. The findings indicate a time-dependent role for basolateral amygdala muscarinic receptors in memory consolidation underlying CPPs for natural and drug rewards.

Amphetamine↗
PubMed2003

Lorazepam and scopolamine: A single-dose comparison of effects on human memory and attentional processes.

This placebo-controlled, double-blind, double-dummy, independent groups study directly compared effects of the benzodiazepine, lorazepam (2.0 mg/70 kg orally administered), and the anticholinergic scopolamine (0.6 mg/70 kg subcutaneously administered) on memory and attentional measures hypothesized to differentiate the drugs. At the studied doses, lorazepam and scopolamine produced similar decrements in psychomotor performance, free recall, and overall sensitivity in distinguishing between studied and nonstudied items on a recognition memory test. However, the drugs differed with respect to effects on working memory, response bias, metacognition, subjective awareness, and selective attention. In addition to providing information about the cognitive psychopharmacological profiles of drugs with distinct neurochemical and pharmacological mechanisms of action, this study also informs the understanding of memory and attentional processes.

Adult↗
PubMed1985

Influence of transdermal scopolamine on motion sickness during 7 days' exposure to heavy seas.

We conducted a double-blind, placebo-controlled study to evaluate the efficacy and tolerability of transdermal scopolamine in the prevention of motion sickness (MS) aboard a frigate during 7 days of continuously moderate or heavy seas. Forty-nine healthy sailors with a previous history of MS were randomly assigned to receive a transdermal therapeutic system of scopolamine (TTS-S) or transdermal placebo (TD-P). Patches were placed behind the ears at least 4 hours before departure and were removed 72 hours later. Subjects were observed on days 1 to 4 and 6. In the TTS-S group, both subjective feeling of MS and the incidence of nausea were reduced during the first 2 days. Because of adaptation, differences in signs and symptoms of MS between subjects receiving TTS-S and TD-P disappeared after the second day. During the first 3 days, vomiting occurred less often in the TTS-S group. On day 6, 3 days after removal of the patch, vomiting occurred in 23% of the TTS-S group, probably due to delay in adaptation, but none of the subjects in the TD-P group vomited. Concentration was not adversely influenced, since the ability to work increased in the TTS-S group. During prolonged continuous exposure to heavy and moderate seas, 2.5 cm2 TTS-S discs proved to be efficacious in preventing MS, with xerostomia as a tolerable side effect and no significant ocular side effects.

Administration, Topical↗
PubMed1988

Scopolamine reduces frontal cortex perfusion.

While the cognitive deficits of Alzheimer's disease are considered related to a cholinergic deficit, no attempt has yet been made to test the hypothesis that the characteristic regional cerebral blood flow (rCBF) pattern of Alzheimer's disease may also relate to such a deficit. We therefore measured rCBF using the [133Xe] inhalation technique in 15 young normal subjects before and after induction of reversible cholinergic blockade with scopolamine at doses of 6.1 and 7.3 micrograms/kg i.v. Significant cognitive impairment was observed at both doses, while rCBF changes occurred only at the higher dose. Global CBF was significantly reduced 25 min after scopolamine. The pattern of regional change in CBF was not similar to Alzheimer's disease. Rather than a focal parietotemporal deficit as seen in Alzheimer's disease, we observed a predominantly frontal reduction in flow of about 20%. These results suggest that the frontal but not the parietotemporal deficits seen in several dementing conditions may be related to cholinergic dysfunction.

Acetylcholine↗
PubMed2001

Anisocoria from transdermal scopolamine.

A transdermal scopolamine patch is an effective medication for relieving motion sickness, treating nausea and vomiting from chemotherapy and decreasing withdrawal side-effects from wearing off opioids. A 14-year-old boy with chronic granulomatous disease and severe infection was admitted to the hospital because of left shoulder aspergillus' infection and pain. The patient required high dose opioid to control the shoulder pain. A unilateral fixed and dilated pupil was noted. We assumed this to be related to the advancing central nervous system aspergillosis. After extensive neurological 'work up', we realized that the anisocoria was related to the transdermal scopolamine patch that we had prescribed for weaning off the opioid.

Adjuvants, Anesthesia↗
PubMed2001

Decreased scopolamine yield in field-grown Duboisia plants regenerated from hairy roots.

Hairy root cultures were obtained from hybrid clones of Duboisia myoporoides x D. leichhardtii following transformation by Agrobacterium rhizogenes strain A4. Shoots spontaneously regenerating from the hairy root cultures were rooted and transferred to soil. The plants displayed typical morphological alterations known as hairy root syndrome to varying degrees. PCR analysis confirmed that all transformed plants contained the rolA, rolB and rolC genes, irrespective of the degree of morphological alterations. A field test of the transformed regenerated plants revealed that those plants displaying the strongest hairy root syndrome symptoms had the highest content of the tropane alkaloid scopolamine. However, the overall scopolamine and hyoscyamine yield of all transformed plants was clearly reduced compared to untransformed control plants. These results demonstrate that the A. rhizogenes-transformed plants tested in this study do not provide a viable alternative to agricultural farming of hybrid clones of D. myoporoides x D. leichhardtii obtained by conventional breeding.

Atropine↗
PubMed1988

Transdermal scopolamine-induced psychosis.

Transdermal scopolamine (Transderm-Scop) is being increasingly used for effective prophylaxis of motion sickness. It is reported to have a lower incidence of CNS side effects than orally administered scopolamine. Although uncommon, such side effects occur more often in the elderly, in those with preexisting psychiatric disease, and in patients concurrently taking other medications with anticholinergic activity. Correct diagnosis may be delayed by the occult location of the delivery system, delayed onset of symptoms, prolonged action, absence of peripheral manifestations, and negative toxicologic screening tests. Treatment is usually supportive. Physostigmine should be reserved for the treatment of severe symptoms.

Administration, Cutaneous↗
PubMed1990

Scopolamine withdrawal syndrome.

As travel by air and ship becomes increasingly popular, more and more travelers are using transdermal scopolamine to avoid motion sickness. In fact, it has become almost fashionable for ocean travelers to sit on the sun deck with a patch behind the ear. This article describes withdrawal symptoms in a patient who used transdermal scopolamine beyond the recommended 3 days.

Administration, Cutaneous↗