Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:EXPT02427 (Atropine)
 3,300 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Plasma gastrin concentrations and gastric acid output after modified sham feeding were determined in 20 duodenal ulcer patients. Sham feeding produced an acid response corresponding to 40-68% of the maximal acid output after pentagastrin stimulation, with no significant increase of plasma gastrin concentrations. In eight patients proximal gastric vagotomy almost abolished the acid responses to both insulin hypoglycaemia and sham feeding. Sham feeding in the vagotomised patients did not change the gastrin concentrations in plasma. After pretreatment with benzilonium, an anticholinergic with minimal central nervous effects, plasma gastrin concentrations increased after sham feeding. The study confirms that sham feeding is a poor stimulus for gastrin release in duodenal ulcer patients and supports a cholinergic inhibition of gastrin release. Intravenous injection of benzilonium bromide in a dose close to 70 micrograms/kg, and atropine in the low dose of 30 micrograms/kg inhibited the acid response to sham feeding by about 65%. Atropine in a dose of 50 micrograms/kg virtually abolished the acid sham feeding response, possibly owing to ganglionic or central nervous blockade. Vagal activation of the acid secretory glands does not seem to involve a purely cholinergic neurotransmission.
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PMID:Effect of proximal gastric vagotomy and anticholinergics on the acid and gastrin responses to sham feeding in duodenal ulcer patients. 39 71

The majority of mechanisms proposed to explain epileptic discharge suggest an excessive synaptic input into the cell or possible changes in cellular excitability which result in a decreased firing threshold and in the presence of self-sustained activity. It is likely that these changes are caused by modifications in the membrane receptor sensitivity to a specific neurotransmitter. In view of the above, the purpose of the present study has been to evaluate the sensitivity of the postsynaptic receptor by means of the microiontophoretic applications of substances whose pharmacological effect is known, thus determining its possible involvement in the epileptic process. Changes in cortical excitability were induced by electric stimuli in the sensorimotor cortex of rats anesthetized with urethane (1 g/kg intraperitoneally), immobilized with pancuronium bromide and kept alive with mechanical respiration. The electric stimuli consisted of trains of biphasic pulses, each lasting one millisecond, with a frequency of 100 pps and with a train duration of 1 second. The response of the neuron to acetylcholine was evaluated before and after the kindling had been established. The dosage was measured in nanoamperes of microiontophoretic ejecting current. Extracellular field potentials were recorded with the central barrel of 4-barrel micropipettes. Peripheral barrels were used for iontophoretic applications of Acetylcholine (Ach .1, 1M), Atropine (25mM). One of these barrels containing NaCl (2M) was used for the automatic passage of balancing current.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Rapidly recurring cortical seizures induce changes in neuronal responsiveness to acetylcholine. 129 72

The efficacy of nicotinic transmission in the rat superior cervical ganglion in vitro (24-26 degrees C) was estimated by extracellular recording of the postganglionic compound action potential response to stimulation of the preganglionic nerve at a slow rate (one shock every 60 s). Atropine (2 microM) was included to block muscarinic transmission, and hexamethonium (200-250 microM) was used to produce a submaximal response sensitive to potentiation and inhibition of nicotinic transmission. Upon exposure to 1-100 microM 8-bromo-guanosine 3',5'-cyclic monophosphate (8-Br-cGMP), nicotinic transmission was potentiated by 6 +/- 1% (n = 4) to 89 +/- 5% (n = 5) in a dose-dependent manner. 8-Bromo-adenosine 3',5'-cyclic monophosphate (8-Br-cAMP, 10-100 microM) also potentiated nicotinic transmission (3.8 +/- 0.3% (n = 3) to 43 +/- 4% (n = 3)). However, 8-Br-cGMP was at least 2-fold more effective than 8-Br-cAMP. Sodium nitroprusside (0.1 microM to 1 mM) and sodium azide (0.1-100 microM) were used to stimulate the formation of endogenous cGMP52. Nicotinic transmission was potentiated by these substances also. The response was increased by 3.4 +/- 0.7% (n = 4) to 32 +/- 2% (n = 5) upon exposure to 0.1-100 microM sodium nitroprusside, and by 5.5 +/- 0.9% (n = 3) to 18 +/- 4% (n = 4) upon exposure to 0.1-100 microM sodium azide. Ferricyanide ion (10-100 microM) appeared to be ineffective, as would be expected if the effect of nitroprusside was due to the nitric oxide rather than the cyanide or ferric moieties.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Potentiation of nicotinic transmission in the rat superior cervical sympathetic ganglion: effects of cyclic GMP and nitric oxide generators. 131 4

Under control (intact and laparotomized) conditions, arterial pressure of urethan-anesthetized ferrets rose significantly in response to intragastric copper sulfate (CuSO4; 10 ml of 5 mg/ml). CuSO4 was emetic 75-90% of the time, and a cardiovascular response always immediately preceded and accompanied emetic responses. The cardiovascular response was significantly reduced or abolished by hexamethonium (0.35 mg/kg) pretreatment combined with atropine methyl bromide (1 mg/kg). Addition of the alpha 2-receptor antagonist 2,3-dichloro-alpha-methylbenzylamine HCl (DCMB, 10 mg/kg) and the beta-receptor antagonist propranolol (3 mg/kg) to the hexamethonium and atropine combination prevented its reduction of the cardiovascular response. Given individually, these agents did not alter cardiovascular response, nor did yohimbine (0.30 mg/kg), RS(+/-)-zacopride (0.30 mg/kg), or granisetron (0.50 mg/kg). Only RS(+/-)-zacopride significantly reduced incidence of emesis. Atropine methyl bromide alone, with hexamethonium, or with hexamethonium, propranolol, and DCMB significantly delayed the first emetic episode. Conversely, bilateral abdominal vagotomy significantly reduced the number of vomiting animals without affecting cardiovascular response. These results suggest that the neural pathways mediating the two events are not identical. In another series of experiments, a significantly greater proportion of animals vomited in response to intragastric CuSO4 than to intraduodenal CuSO4, suggesting that the primary site of CuSO4 action in the ferret is the stomach.
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PMID:Surgical and pharmacological dissociation of cardiovascular and emetic responses to intragastric CuSO4. 135 43

Although five muscarinic receptor subtypes have now been cloned, only three receptor subtypes have been demonstrated pharmacologically in bronchial tissue (designated M1, M2 and M3). By using drugs that show selectivity for these receptor subtypes, in combination with a sensitive and specific high-pressure liquid chromatography method that enables the direct measurement of acetylcholine (ACh) release, the existence and function of these muscarinic receptor subtypes was investigated in rabbit trachea in vitro. Atropine and ipratropium bromide, nonselective antimuscarinic agents, dose-dependently suppressed contraction of rabbit trachea induced by transmural electrical stimulation, but at the same time enhanced the release of ACh, suggesting the presence of an autoregulatory feed-back system. The M2/M4 receptor antagonists methoctramine, 11-((2-[(diethylamino)methyl]-1-piperidinyl)acetyl)-5, 11-dihydro-6H-pyrido(2,3-b)(1,4)benzodiazepine-6-one, 5,11-dihydro-11-([(2-(2-[(dipropylamino)methyl]-1-piperidinyl)ethyl) amino]carbonyl)-6H-pyrido(2,3-b)(1,4)benzodiazepine-6-one and 11-((4-[4-(diethylamino)butyl]-1-piperidinyl)acetyl)-5, 11-dihydro-6H-pyrido(2,3-b)(1,4)benzodiazepine-6-one also dose-dependently increased ACh release during electrical stimulation, indicating that the powerful negative feedback system is mediated by presynaptic autoreceptors of the M2 or M4 type.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Selective M3 muscarinic receptor antagonists inhibit smooth muscle contraction in rabbit trachea without increasing the release of acetylcholine. 135 17

Atropine (1 mg intravenously) and a new antimuscarinic compound, cimetropium bromide (5 mg intravenously), as well as placebo (physiological saline) were tested for their effects on gastric emptying and antroduodenal motility in healthy humans. In a first single-blind cross-over study, the emptying rate was assessed in 12 subjects by measuring paracetamol absorption. In a second single-blind parallel-group study, antroduodenal motor activity was measured in 20 subjects through four perfused open tip catheters with orifices positioned in the antroduodenal region. Atropine, unlike cimetropium bromide, significantly delayed gastric emptying. Antral and duodenal motility index was reduced significantly by atropine, but not by cimetropium bromide. Heart rate significantly increased only after atropine. Three subjects taking atropine complained of dry mouth and one of blurred vision. In conclusion, the results of these studies show that atropine, unlike cimetropium bromide, strongly inhibits gastric emptying of liquids and reduces antroduodenal motor activity in man.
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PMID:Different effects of atropine and cimetropium bromide on gastric emptying of liquids and antroduodenal motor activity in man. 234 Nov 21

The effects of flutropium bromide (Ba598Br), a new antiasthma drug possessing the quarternary ammonium structure of atropine derivatives, on mediator release from mast cells and on actions of leukotriene (LT) D4 and serotonin were investigated. Flutropium bromide (3 and 10 mg/kg, i.v.) showed an inhibitory action on the 48 hr homologous PCA in guinea pigs. Atropine showed no inhibitory effect. Flutropium bromide also inhibited the release of histamine from isolated rat mast cells stimulated by antigen, although the inhibitory action was weaker than that of disodium cromoglycate. Atropine also had no inhibitory action in this case. Flutropium bromide and atropine showed no antagonistic action against LTD4-induced contraction of isolated tracheal smooth muscle of guinea pigs. Inhalation of flutropium bromide (0.3%) also showed no antagonistic action against serotonin-induced bronchoconstriction in dogs. From the above results, it is indicated that flutropium bromide has a weak mast cell stabilizing action, but no antagonistic action against LTD4 and serotonin.
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PMID:[Effects of flutropium bromide, a new antiasthma drug, on mediator release from mast cells and actions of mediators]. 245 23

Effects of oxitropium bromide (Ba253), which was administered by inhalation, on the resting and stimulus-induced airway resistance were examined in the artificially ventilated guinea pig and compared with those of ipratropium bromide (Sch1000), atropine and isoproterenol. Results obtained were as follows: 1) Ba253 as well as other reference compounds hardly affected the resting resistance. 2) Ba253 strongly and persistently inhibited the acetylcholine (ACh)-induced resistance. Sch1000 caused a similar but relatively weaker inhibition than Ba253. Either atropine or isoproterenol caused only a transient inhibition. 3) The increase in resistance induced by histamine, serotonin, leukotriene D4 or antigen was prevented by Ba253. Atropine, Sch1000 and isoproterenol also inhibited these reactions, but the effects and the duration were generally weaker and shorter than those of Ba253. 4) Repeated inhalations of Ba253 for 7 days did not influence the inhibition of the ACh-induced increase in airway resistance by this drug. However, isoproterenol tended to attenuate the suppression of the resistance by the drug. From these results, it is suggested that Ba253 is a useful inhalant drug for asthma.
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PMID:Effect of oxitropium bromide (Ba253) on increased airway resistance induced by various agonists and antigen in the guinea pig. 252 46

The principles of aerosol drug delivery by compressed-air nebulization are described, and the therapeutic agents administered by this process for management of asthma are reviewed. For therapy of acute and chronic asthma, aerosol inhalation has become the primary method of drug administration. Aerosolized particles with aerodynamic diameters of 1 to 5 microns are most efficiently deposited in the lower respiratory tract. Delivery systems for therapeutic aerosols include compressed-air nebulizers and metered-dose inhalers. Compressed-air nebulizers are less efficient than metered-dose inhalers; therefore, the drug dosages recommended for nebulizer solutions are 3 to 10 times higher than those delivered by a metered-dose inhaler. Because many asthma patients are treated with nebulization drug therapy at home, both patients and pharmacists must understand how to use the equipment correctly. Drugs used in aerosol therapy of acute and chronic asthma include the beta 2-receptor agonists epinephrine, isoproterenol, isoetharine, metaproterenol, terbutaline, and albuterol; cromolyn sodium; and the anticholinergic agents atropine and ipratropium bromide. Terbutaline and albuterol have longer durations of action and greater beta 2-receptor selectivity than metaproterenol, isoetharine, and isoproterenol. Cromolyn is a first-line prophylactic agent for asthma management. Atropine is indicated for maintenance therapy of chronic asthma and in combination with the beta 2-receptor agonists for therapy of acute asthma; ipratropium bromide is a new agent similar to atropine but with substantially fewer adverse effects. Acute and chronic asthma may be managed by aerosol administration of beta 2-receptor agonists, cromolyn, and atropine, alone or in combination. Inhalation is the preferred route of drug delivery because small doses of medication provide maximal therapeutic benefit with minimal adverse effects.
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PMID:Principles of nebulizer-delivered drug therapy for asthma. 267 64

The effect of cimetropium bromide, a new antimuscarinic compound, on bethanechol- and electrically-induced contractions was studied on isolated guinea-pig gallbladder. Atropine and two other widely employed antispasmodics (i.e., rociverine and octylonium bromide) were employed as reference compounds. Cimetropium and atropine proved to be competitive antimuscarinics, their pA2 being 7.77 +/- 0.14 and 8.31 +/- 0.14, respectively. On the contrary, rociverine displayed a dual effect being a competitive antagonist at low (up to 10(-5) mol/l) and a mixed one at high (greater than 10(-5) mol/l) concentrations. When tested against bethanechol- and electrically-induced contractions, all the compounds, with the exception of octylonium bromide, showed a concentration-dependent relaxant effect. In both experimental conditions, the potency of cimetropium was of the same order of magnitude as that of atropine and 150-200 times higher than that of rociverine. These data, together with the reported activity on human gallbladder in vivo and the well known involvement of cholinergic system in the control of gallbladder motility, could represent the rationale for the clinical use of cimetropium in the treatment of biliary colics as well as spasms of biliary tree.
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PMID:Effect of cimetropium bromide and other antispasmodic compounds on in vitro guinea-pig gallbladder. 275 78


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