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Scopolamine (Hyoscine) is an approved medication used to treat motion sickness and postoperative nausea and vomiting. It acts as a competitive and non-selective antagonist of muscarinic acetylcholine receptor with an IC50 of 55.3 nM.
ln Vitro |
In oocytes expressing 5-HT3-blocked oocytes, scopolamine did not elicit a response when applied alone; however, when scopolamine was applied concurrently with 2 μM 5-HT, the response was inhibited dependent on the concentration. With n = 6, the scopolamine pIC50 value is 5.68±0.05 (IC50=2.09) μM, the Hill Slope is 1.06±0.05, and the Kb is 3.23 μM. Scopolamine was applied during 5-HT administration, and the same concentration-dependent effects were seen. In order to conduct additional testing of competitive binding to the 5-HT3 receptor, [3H]granisetron, a well-known high-affinity competitive antagonist, was used to assess the competitiveness of unlabeled scopolamine. Scopolamine, with an average pKi of 5.17±0.24 (Ki=6.76 μM, n=3), shows concentration nutritional competition at 0.6 nM [3H]granisetron (~Kd)[1].
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ln Vivo |
In animal models of Alzheimer's disease, scopolamine can be used to create models of the disease. In histopathological studies, there were no significant changes in the brain's histology; however, acetylcholinesterase (AchE) activity (7.98±0.065; P<0.001) in the hippocampal cells of molds that received scopolamine only in tap water compared with the normal group (3.06±0.296). Moreover, scopolamine-treated animals had significantly higher levels of malondialdehyde (MDA) (34.61±4.85; P<0.01) compared to the normal group (12.82±2.86). The scopolamine-treated group (0.3906±0.02) showed still prototype glutathione (GSH); in comparison to the normal group (43.21±3.46), the amyloid (Aβ1-42) concentration in the scop
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ADME/Pharmacokinetics |
Absorption, Distribution and Excretion
The pharmacokinetics of scopolamine differ substantially between different dosage routes. Oral administration of 0.5 mg scopolamine in healthy volunteers produced a Cmax of 0.54 ± 0.1 ng/mL, a tmax of 23.5 ± 8.2 min, and an AUC of 50.8 ± 1.76 ng\*min/mL; the absolute bioavailability is low at 13 ± 1%, presumably because of first-pass metabolism. By comparison, IV infusion of 0.5 mg scopolamine over 15 minutes resulted in a Cmax of 5.00 ± 0.43 ng/mL, a tmax of 5.0 min, and an AUC of 369.4 ± 2.2 ng\*min/mL. Other dose forms have also been tested. Subcutaneous administration of 0.4 mg scopolamine resulted in a Cmax of 3.27 ng/mL, a tmax of 14.6 min, and an AUC of 158.2 ng\*min/mL. Intramuscular administration of 0.5 scopolamine resulted in a Cmax of 0.96 ± 0.17 ng/mL, a tmax of 18.5 ± 4.7 min, and an AUC of 81.3 ± 11.2 ng\*min/mL. Absorption following intranasal administration was found to be rapid, whereby 0.4 mg of scopolamine resulted in a Cmax of 1.68 ± 0.23 ng/mL, a tmax of 2.2 ± 3 min, and an AUC of 167 ± 20 ng\*min/mL; intranasal scopolamine also had a higher bioavailability than that of oral scopolamine at 83 ± 10%. Due to dose-dependent adverse effects, the transdermal patch was developed to obtain therapeutic plasma concentrations over a longer period of time. Following patch application, scopolamine becomes detectable within four hours and reaches a peak concentration (tmax) within 24 hours. The average plasma concentration is 87 pg/mL, and the total levels of free and conjugated scopolamine reach 354 pg/mL. Following oral administration, approximately 2.6% of unchanged scopolamine is recovered in urine. Compared to this, using the transdermal patch system, less than 10% of the total dose, both as unchanged scopolamine and metabolites, is recovered in urine over 108 hours. Less than 5% of the total dose is recovered unchanged. The volume of distribution of scopolamine is not well characterized. IV infusion of 0.5 mg scopolamine over 15 minutes resulted in a volume of distribution of 141.3 ± 1.6 L. IV infusion of 0.5 mg scopolamine resulted in a clearance of 81.2 ± 1.55 L/h, while subcutaneous administration resulted in a lower clearance of 0.14-0.17 L/h. Scopolamine hydrobromide is rapidly absorbed following IM or subcutaneous injection. The drug is well absorbed from the GI tract, principally from the upper small intestine. Scopolamine also is well absorbed percutaneously. Following topical application behind the ear of a transdermal system, scopolamine is detected in plasma within 4 hours, with peak concentrations occurring within an average of 24 hours. In one study in healthy individuals, mean free and total (free plus conjugated) plasma scopolamine concentrations of 87 and 354 pg/mL, respectively, have been reported within 24 hours following topical application of a single transdermal scopolamine system that delivered approximately 1 mg/72 hours. /Scopolamine hydrobromide/ Following oral administration of a 0.906-mg dose of scopolamine in one individual, a peak concentration of about 2 ng/mL was reached within 1 hour. Although the commercially available transdermal system contains 1.5 mg of scopolamine, the membrane-controlled diffusion system is designed to deliver approximately 1 mg of the drug to systemic circulation at an approximately constant rate over a 72-hour period. An initial priming dose of 0.14 mg of scopolamine is released from the adhesive layer of the system at a controlled, asymptotically declining rate over 6 hours; then, the remainder of the dose is released at an approximate rate of 5 ug/hour for the remaining 66-hour functional lifetime of the system. The manufacturer states that the initial priming dose saturates binding sites on the skin and rapidly brings the plasma concentration to steady-state. In a crossover study comparing urinary excretion rates of scopolamine during multiple 12-hour collection intervals in healthy individuals, there was no difference between the rates of excretion of drug during steady-state (24-72 hours) for constant-rate IV infusion (3.7-6 mcg/hour) and transdermal administration. The transdermal system appeared to deliver the drug to systemic circulation at the same rate as the constant-rate IV infusion; however, relatively long collection intervals (12 hours) make it difficult to interpret the data precisely. During the 12- to 24-hour period of administration and after 72 hours, the rate of excretion of scopolamine was higher with the transdermal system than with the constant-rate IV infusion. The distribution of scopolamine has not been fully characterized. The drug appears to be reversibly bound to plasma proteins. Scopolamine apparently crosses the blood-brain barrier since the drug causes CNS effects. The drug also reportedly crosses the placenta and is distributed into milk.. Although the metabolic and excretory fate of scopolamine has not been fully determined, the drug is thought to be almost completely metabolized (principally by conjugation) in the liver and excreted in urine. Following oral administration of a single dose of scopolamine in one study, only small amounts of the dose (about 4-5%) were excreted unchanged in urine within 50 hours; urinary clearance of unchanged drug was about 120 mL/minute. In another study, 3.4% or less than 1% of a single dose was excreted unchanged in urine within 72 hours following subcutaneous injection or oral administration of the drug, respectively. Following application of a single transdermal scopolamine system that delivered approximately 1 mg/72 hours in healthy individuals, the urinary excretion rate of free and total (free plus conjugated) scopolamine was about 0.7 and 3.8 ug/hour, respectively. Following removal of the transdermal system of scopolamine, depletion of scopolamine bound to skin receptors at the site of the application of the transdermal system results in a log-linear decrease in plasma scopolamine concentrations. Less than 10% of the total dose is excreted in urine as unchanged drug and its metabolites over 108 hours. Metabolism / Metabolites Little is known about the metabolism of scopolamine in humans, although many metabolites have been detected in animal studies. In general, scopolamine is primarily metabolized in the liver, and the primary metabolites are various glucuronide and sulphide conjugates. Although the enzymes responsible for scopolamine metabolism are unknown, _in vitro_ studies have demonstrated oxidative demethylation linked to CYP3A subfamily activity, and scopolamine pharmacokinetics were significantly altered by coadministration with grapefruit juice, suggesting that CYP3A4 is responsible for at least some of the oxidative demethylation. Although the metabolic and excretory fate of scopolamine has not been fully determined, the drug is thought to be almost completely metabolized (principally by conjugation) in the liver and excreted in urine. Biological Half-Life The half-life of scopolamine differs depending on the route. Intravenous, oral, and intramuscular administration have similar half-lives of 68.7 ± 1.0, 63.7 ± 1.3, and 69.1 ±8/0 min, respectively. The half-life is greater with subcutaneous administration at 213 min. Following removal of the transdermal patch system, scopolamine plasma concentrations decrease in a log-linear fashion with a half-life of 9.5 hours. Following application of a single transdermal scopolamine system that delivered approximately 1 mg/72 hours, the average elimination half-life of the drug was 9.5 hours. |
Toxicity/Toxicokinetics |
Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation No information is available on the use of scopolamine during breastfeeding. Use during labor appears to have a detrimental effect on newborn infants' nursing behavior. Long-term use of scopolamine might reduce milk production or milk letdown, but a single systemic or ophthalmic dose is not likely to interfere with breastfeeding. During long-term use, observe for signs of decreased lactation (e.g., insatiety, poor weight gain). To substantially diminish the amount of drug that reaches the breastmilk after using eye drops, place pressure over the tear duct by the corner of the eye for 1 minute or more, then remove the excess solution with an absorbent tissue. ◉ Effects in Breastfed Infants Relevant published information was not found as of the revision date. ◉ Effects on Lactation and Breastmilk Anticholinergics can inhibit lactation in animals, apparently by inhibiting growth hormone and oxytocin secretion. Anticholinergic drugs can also reduce serum prolactin in nonnursing women. The prolactin level in a mother with established lactation may not affect her ability to breastfeed. A retrospective case-control study conducted in two hospitals in central Iran compared breastfeeding behaviors in the first 2 hours postdelivery by infants of 4 groups of primiparous women with healthy, full-term singleton births who had vaginal deliveries. The groups were those who received no medications during labor, those who received oxytocin plus scopolamine, those who received oxytocin plus meperidine, and those who received oxytocin, scopolamine and meperidine. The infants in the no medication group performed better than those in all other groups, and the oxytocin plus scopolamine group performed better than the groups that had received meperidine. Protein Binding Scopolamine may reversibly bind plasma proteins in humans. In rats, scopolamine exhibits relatively low plasma protein binding of 30 ± 10%. Interactions Scopolamine should be used with care in patients taking other drugs that are capable of causing CNS effects such as sedatives, tranquilizers, or alcohol. Special attention should be paid to potential interactions with drugs having anticholinergic properties; e.g., other belladonna alkaloids, antihistamines (including meclizine), tricyclic antidepressants, and muscle relaxants. The absorption of oral medications may be decreased during the concurrent use of scopolamine because of decreased gastric motility and delayed gastric emptying. Concomitant administration of antimuscarinics and corticosteroids may result in increased intraocular pressure. /Antimuscarinics/Antispasmodics/ Antacids may decrease the extent of absorption of some oral antimuscarinics when these drugs are administered simultaneously. Therefore, oral antimuscarinics should be administered at least 1 hour before antacids. Antimuscarinics may be administered before meals to prolong the effects of postprandial antacid therapy. However, controlled studies have failed to demonstrate a substantial difference in gastric pH when combined antimuscarinic and antacid therapy was compared with antacid therapy alone. /Antimuscarinics/Antispasmodics/ For more Interactions (Complete) data for SCOPOLAMINE (8 total), please visit the HSDB record page. |
References |
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Additional Infomation |
Therapeutic Uses
Adjuvants, Anesthesia; Antiemetics; Muscarinic Antagonists; Mydriatics; Parasympatholytics Although transdermal scopolamine has been shown to decrease basal acid output and inhibit betazole-, pentagastrin-, and peptone-stimulated gastric acid secretion in healthy individuals, it has not been determined whether transdermal scopolamine is effective in the adjunctive treatment of peptic ulcer disease. /Use is not currently included in the labeling approved by the US FDA/ Transdermal scopolamine has shown minimal antiemetic activity against chemotherapy-induced vomiting. /Use is not currently included in the labeling approved by the US FDA/ Scopolamine hydrobromide is used as a mydriatic and cycloplegic, especially when the patient is sensitive to atropine or when less prolonged cycloplegia is required. The effects of the drug appear more rapidly and have a shorter duration of action than those of atropine. Scopolamine hydrobromide is also used in the management of acute inflammatory conditions (i.e., iridocyclitis) of the iris and uveal tract. /Scopolamine hydrobromide/ For more Therapeutic Uses (Complete) data for SCOPOLAMINE (10 total), please visit the HSDB record page. Drug Warnings The use of scopolamine to produce tranquilization and amnesia in a variety of circumstances, including labor, is declining and of questionable value. Given alone in the presence of pain or severe anxiety, scopolamine may induce outbursts of uncontrolled behavior. Scopolamine in therapeutic doses normally causes CNS depression manifested as drowsiness, amnesia, fatigue, and dreamless sleep, with a reduction in rapid eye movement (REM) sleep. It also causes euphoria and is therefore subject to some abuse. The depressant and amnesic effects formerly were sought when scopolamine was used as an adjunct to anesthetic agents or for preanesthetic medication. However, in the presence of severe pain, the same doses of scopolamine can occasionally cause excitement, restlessness, hallucinations, or delirium. These excitatory effects resemble those of toxic doses of atropine. Scopolamine-induced inhibition of salivation occurs within 30 minutes or within 30 minutes to 1 hour and peaks within 1 or 1-2 hours after IM or oral administration, respectively; inhibition of salivation persists for up to 4-6 hours. Following IV administration of a 0.6-mg dose in one study, amnesia occurred within 10 minutes, peaked between 50-80 minutes, and persisted for at least 120 minutes after administration. Following IM administration of a 0.2-mg dose of scopolamine in one study, antiemetic effect occurred within 15-30 minutes and persisted for about 4 hours. Following IM administration of a 0.1- or 0.2-mg dose in another study, mydriasis persisted for up to 8 hours. The transdermal system is designed to provide an antiemetic effect with an onset of about 4 hours and with a duration of up to 72 hours after application. Small doses of ... scopolamine inhibit the activity of sweat glands innervated by sympathetic cholinergic fibers, and the skin becomes hot and dry. Sweating may be depressed enough to raise the body temperature, but only notably so after large doses or at high environmental temperatures. For more Drug Warnings (Complete) data for SCOPOLAMINE (21 total), please visit the HSDB record page. Pharmacodynamics Scopolamine is an anticholinergic belladonna alkaloid that, through competitive inhibition of muscarinic receptors, affects parasympathetic nervous system function and acts on smooth muscles that respond to acetylcholine but lack cholinergic innervation. Formulated as a patch, scopolamine is released continuously over three days and remains detectable in urine over a period of 108 hours. Scopolamine is contraindicated in angle-closure glaucoma and should be used with caution in patients with open-angle glaucoma due to scopolamine's ability to increase intraocular pressure. Also, scopolamine exhibits several neuropsychiatric effects: exacerbated psychosis, seizures, seizure-like, and other psychiatric reactions, and cognitive impairment; scopolamine may impair the ability of patients to operate machinery or motor vehicles, play underwater sports, or perform any other potentially hazardous activity. Women with severe preeclampsia should avoid scopolamine. Patients with gastrointestinal or urinary disorders should be monitored frequently for impairments, and scopolamine should be discontinued if these develop. Scopolamine can cause blurred vision if applied directly to the eye, and the transdermal patch should be removed before an MRI procedure to avoid skin burns. Due to its gastrointestinal effects, scopolamine can interfere with gastric secretion testing and should be discontinued at least 10 days before performing the test. Finally, scopolamine may induce dependence and resulting withdrawal symptoms, such as nausea, dizziness, vomiting, gastrointestinal disturbances, sweating, headaches, bradycardia, hypotension, and various neuropsychiatric manifestations following treatment discontinuation; severe symptoms may require medical attention. |
Molecular Formula |
C17H21NO4
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Molecular Weight |
303.35
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Exact Mass |
303.147
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CAS # |
51-34-3
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Related CAS # |
Scopolamine hydrobromide;114-49-8;Scopolamine butylbromide;149-64-4;Scopolamine hydrobromide trihydrate;6533-68-2;Scopolamine hydrochloride;55-16-3
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PubChem CID |
11968014
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Appearance |
White to off-white <55°C powder,>55°C liquid
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Density |
1.3±0.1 g/cm3
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Boiling Point |
460.3±45.0 °C at 760 mmHg
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Melting Point |
59ºC
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Flash Point |
232.2±28.7 °C
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Vapour Pressure |
0.0±1.2 mmHg at 25°C
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Index of Refraction |
1.614
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LogP |
0.76
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Hydrogen Bond Donor Count |
1
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Hydrogen Bond Acceptor Count |
5
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Rotatable Bond Count |
5
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Heavy Atom Count |
22
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Complexity |
418
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Defined Atom Stereocenter Count |
5
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SMILES |
O1[C@]2([H])[C@@]3([H])C([H])([H])C([H])(C([H])([H])[C@@]([H])([C@]12[H])N3C([H])([H])[H])OC([C@@]([H])(C1C([H])=C([H])C([H])=C([H])C=1[H])C([H])([H])O[H])=O
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InChi Key |
STECJAGHUSJQJN-SFSMXDMGSA-N
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InChi Code |
InChI=1S/C17H21NO4/c1-18-13-7-11(8-14(18)16-15(13)22-16)21-17(20)12(9-19)10-5-3-2-4-6-10/h2-6,11-16,19H,7-9H2,1H3/t11?,12-,13-,14+,15+,16+/m1/s1
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Chemical Name |
[(1R,2S,4S,5S)-9-methyl-3-oxa-9-azatricyclo[3.3.1.02,4]nonan-7-yl] (2S)-3-hydroxy-2-phenylpropanoate
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Synonyms |
Scopolamine Transderm SCOP l-Scopolamine SEE
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HS Tariff Code |
2934.99.9001
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Storage |
Powder -20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light. |
Shipping Condition |
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
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Solubility (In Vitro) |
DMSO : ~100 mg/mL (~329.65 mM)
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Solubility (In Vivo) |
Solubility in Formulation 1: ≥ 2.5 mg/mL (8.24 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.5 mg/mL (8.24 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C,1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. View More
Solubility in Formulation 3: ≥ 2.5 mg/mL (8.24 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. |
Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
1 mM | 3.2965 mL | 16.4826 mL | 32.9652 mL | |
5 mM | 0.6593 mL | 3.2965 mL | 6.5930 mL | |
10 mM | 0.3297 mL | 1.6483 mL | 3.2965 mL |
*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.
Calculation results
Working concentration: mg/mL;
Method for preparing DMSO stock solution: mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.
Method for preparing in vivo formulation::Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O,mix and clarify.
(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
(2) Be sure to add the solvent(s) in order.
NCT Number | Recruitment | interventions | Conditions | Sponsor/Collaborators | Start Date | Phases |
NCT04314713 | TERMINATED | Drug: Scopolamine Hydrobromide Trihydrate | Scopolamine Causing Adverse Effects in Therapeutic Use | Battelle Memorial Institute | 2020-06-02 | Phase 1 |
NCT03029650 | COMPLETEDWITH RESULTS | Drug: Transderm Scop® Drug: Intravenous scopolamine hydrobromide |
Healthy | University of Iowa | 2016-11 | Phase 4 |
NCT03874130 | UNKNOWN STATUS | Drug: Scopolamine | Major Depressive Disorder (MDD) | Repurposed Therapeutics, Inc. | 2018-08-01 | Phase 1 |
NCT02516098 | COMPLETEDWITH RESULTS | Drug: hyoscine butylbromide | Healthy | Boehringer Ingelheim | 2015-10 | Phase 1 |
NCT04349722 | COMPLETED | Drug: Hyoscine Butylbromide Other: Placebo |
Labor Long | National University of Malaysia | 2019-12-01 | Phase 4 |
Chemical structures of endogenous agonist 5-HT, 5-HT3 receptor antagonists granisetron, tropisetron and SDZ-ICT 322, scopolamine, atropine and the radioligand [3H]N-methylscopolamine. Note that scopolamine is a single enantiomer whereas atropine is a mixture of epimers at the indicated (asterisk) carbon atom.[1]. Lochner M, et al. The muscarinic antagonists Scopolamine and atropine are competitive antagonists at 5-HT3 receptors. Neuropharmacology. 2016 Sep;108:220-8. td> |
The effect of scopolamine on 5-HT3 receptor currents. (A) Concentration-response curve for 5-HT. (B) Concentration-inhibition of the 2 μM 5-HT response by co-applied scopolamine. The data in 2A are normalised to the maximal peak current response for each oocyte and represented as the mean ± S.E.M. for a series of oocytes. In Fig. 2B, inhibition by scopolamine is shown relative to the peak current response to 2 μM 5-HT alone. For 5-HT curve fitting yielded a pEC50 of 5.65 ± 0.02 (EC50 = 2.24 μM, n = 6) and Hill slope of 2.06 ± 0.14. The pIC50 value for scopolamine was 5.68 ± 0.05 (IC50 = 2.09 μM, n = 6) with a Hill Slope of 1.06 ± 0.05. (C) Sample traces showing the onset (τon) and recovery (τoff) of scopolamine inhibition (grey bar) during a 2 μM 5-HT application (filled bar). (D) Onset of inhibition was well fitted by mono-exponential functions to give kobs (n = 17). A plot of the reciprocal of these time constants versus the scopolamine concentration showed a linear relationship where the slope = kon (2.60 × 104 M−1 s−1) and the y-axis intercept = koff (0.32 s−1).[1]. Lochner M, et al. The muscarinic antagonists Scopolamine and atropine are competitive antagonists at 5-HT3 receptors. Neuropharmacology. 2016 Sep;108:220-8. td> |
The mechanism of 5-HT3 receptor inhibition by scopolamine. (A) Concentration-response curves were performed in the absence or presence of the indicated concentrations of scopolamine. The curves showed parallel dextral shifts with maximal currents restored by increasing concentrations of 5-HT. Parameters derived from these curves can be seen in Table 1. (B) A Schild plot was created from the dose ratios of the curves shown in 3A and fitted with Eq. (3) to yield a slope of 1.06 ± 0.10 (R2 = 0.97) and a pA2 of 5.03 ± 0.43 (Kb, 9.33 μM).[1]. Lochner M, et al. The muscarinic antagonists Scopolamine and atropine are competitive antagonists at 5-HT3 receptors. Neuropharmacology. 2016 Sep;108:220-8. td> |