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Postgraduate Medical Journal May 1972Antazoline was administered in sixty-five episodes of various types of cardiac arrhythmia. A complete suppression of the ectopic beats was achieved in five out of six...
Antazoline was administered in sixty-five episodes of various types of cardiac arrhythmia. A complete suppression of the ectopic beats was achieved in five out of six episodes of premature atrial systoles and in twenty-one of the twenty-four episodes of ventricular premature systoles. Conversion to sinus rhythm was observed in seven out of ten and four out of five episodes of paroxysmal atrial and nodal tachycardia respectively. Six out of ten episodes of ventricular tachycardia were controlled by intravenous therapy. However, the drug proved to be ineffective in cases of atrial fibrillation. The side-effects were few and transitory, consisting of nausea, vomiting and drowsiness.
Topics: Administration, Oral; Adolescent; Adult; Aged; Antazoline; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Electrocardiography; Female; Humans; Infusions, Intravenous; Male; Middle Aged; Treatment Outcome; Young Adult
PubMed: 18557243
DOI: 10.1136/pgmj.48.559.304 -
British Medical Journal Nov 1979
Topics: Adult; Alveolitis, Extrinsic Allergic; Antazoline; Erythema; Female; Humans; Imidazoles
PubMed: 519432
DOI: 10.1136/bmj.2.6201.1328 -
British Journal of Pharmacology Dec 19931. In rat whole portal veins, guanabenz (100 nM to 10 microM) and antazoline (100 nM to 100 microM) each increased the amplitude, frequency and duration of spontaneous...
1. In rat whole portal veins, guanabenz (100 nM to 10 microM) and antazoline (100 nM to 100 microM) each increased the amplitude, frequency and duration of spontaneous contractions. In addition, guanabenz (30 microM) and antazoline (30 microM) each antagonized the ability of levcromakalim (3 nM to 10 microM) to inhibit the spontaneous contractions of this tissue. 2. Whole-cell voltage-clamp recordings were made from freshly-isolated rat portal vein cells dispersed by a collagenase/pronase enzyme treatment. The ability of several agents (antazoline, cirazoline, clonidine, guanabenz and phentolamine, each containing an imidazoline or guanidine moiety), to modulate potassium (K) currents and to inhibit the actions of levcromakalim was investigated. 3. Antazoline, cirazoline, clonidine, guanabenz and phentolamine (each at a concentration of 30 microM) had little effect on control non-inactivating currents but inhibited the delayed-rectifier current, IK(V). 4. Levcromakalim (1 microM) induced a non-inactivating current, IK(ATP), and also inhibited the delayed rectifier current, IK(V). 5. Glibenclamide (1 microM) had no effect on control delayed rectifier or non-inactivating currents, but it inhibited the simultaneous induction of IK(ATP) and reduction of IK(V) produced by levcromakalim (1 microM). 6. Antazoline, cirazoline, clonidine and guanabenz (each at a concentration of 30 microM) prevented the induction of IK(ATP) by levcromakalim (1 microM). Phentolamine (30 microM) and clonidine (30 microM) each inhibited the IK(ATP) generated by levcromakalim (1 microM). 7. It is concluded that a variety of agents which possess either an imidazoline (antazoline, cirazoline, clonidine and phentolamine) or a guanidine (guanabenz) moiety within their structure inhibit the delayed rectifier current, IK(V). This action may thus be mediated via a so-called non-adrenoceptor imidazoline binding site. Furthermore, the ability of these ligands to inhibit IK(V) and to antagonize both the induction of IK(ATP) and the vasorelaxation produced by levcromakalim is consistent with the view that the channel (KATP) which underlies IK(ATP) is a voltage-insensitive state of the delayed rectifier K-channel (Kv).
Topics: Animals; Antazoline; Benzopyrans; Clonidine; Cromakalim; Glyburide; Guanabenz; Imidazoline Receptors; Male; Phentolamine; Portal Vein; Potassium Channels; Pyrroles; Rats; Rats, Sprague-Dawley; Receptors, Drug
PubMed: 8306101
DOI: 10.1111/j.1476-5381.1993.tb14001.x -
Cardiovascular Therapeutics Apr 2017The antihistaminic antazoline (ANT) was reported to be highly effective and safe for rapid conversion of atrial fibrillation (AF). We therefore analyzed underlying...
INTRODUCTION
The antihistaminic antazoline (ANT) was reported to be highly effective and safe for rapid conversion of atrial fibrillation (AF). We therefore analyzed underlying mechanisms in an experimental whole-heart model.
METHODS AND RESULTS
Isolated and retrogradely perfused rabbit hearts underwent a standardized protocol employing atrial burst pacing-induced AF in five of 20 hearts under baseline conditions (seven episodes). Thereafter, a combination of acetylcholine and isoproterenol was employed to enhance AF occurrence. Two monophasic action potential recordings on the left- and two on the right atrial epicardium showed a decrease in atrial action potential duration (aAPD, -25 msec, P<.05) and atrial effective refractory period (aERP; -52 msec, P<.01) after infusion of acetylcholine (1 μmol/L) and isoproterenol (1 μmol/L). This led to induction of AF in 14 of 20 hearts (145 episodes). Simultaneous infusion of ANT (20 μmol/L) led to a complete suppression of AF in all inducible hearts. Treatment with ANT also led to a significant increase in aAPD (+41 msec, P<.01) and aERP (+74 msec, P<.05), leading to a marked increase in atrial postrepolarization refractoriness (aPRR, +33 msec, P<.01). Results were compared to 13 rabbits treated with flecainide. Flecainide induced a significant increase in aPRR and resulted in induction of AF in seven of 13 hearts (51 episodes) while 11 of 13 hearts were inducible with acetylcholine and isoproterenol (93 episodes).
CONCLUSION
Administration of ANT was highly effective in suppressing AF. The antiarrhythmic effect could be explained by a significant increase in postrepolarization refractoriness as a result of a more marked increase in aERP as compared with aAPD.
Topics: Acetylcholine; Action Potentials; Animals; Antazoline; Anti-Arrhythmia Agents; Atrial Fibrillation; Cardiac Pacing, Artificial; Dose-Response Relationship, Drug; Drug Discovery; Electrocardiography; Electrophysiologic Techniques, Cardiac; Flecainide; Heart Rate; Histamine H1 Antagonists; Isolated Heart Preparation; Isoproterenol; Rabbits; Refractory Period, Electrophysiological; Time Factors
PubMed: 28039911
DOI: 10.1111/1755-5922.12244 -
Polish Archives of Internal Medicine Apr 2024
Topics: Atrial Fibrillation; Humans; Anti-Arrhythmia Agents
PubMed: 38666721
DOI: 10.20452/pamw.16741 -
British Journal of Pharmacology Jul 1999This study was designed to assess the potential neuroprotective effect of several imidazol(ine) drugs and agmatine on glutamate-induced necrosis and on apoptosis induced... (Comparative Study)
Comparative Study
This study was designed to assess the potential neuroprotective effect of several imidazol(ine) drugs and agmatine on glutamate-induced necrosis and on apoptosis induced by low extracellular K+ in cultured cerebellar granule cells. Exposure (30 min) of energy deprived cells to L-glutamate (1-100 microM) caused a concentration-dependent neurotoxicity, as determined 24 h later by a decrease in the ability of the cells to metabolize 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) into a reduced formazan product. L-glutamate-induced neurotoxicity (EC50=5 microM) was blocked by the specific NMDA receptor antagonist MK-801 (dizocilpine). Imidazol(ine) drugs and agmatine fully prevented neurotoxicity induced by 20 microM (EC100) L-glutamate with the rank order (EC50 in microM): antazoline (13)>cirazoline (44)>LSL 61122 [2-styryl-2-imidazoline] (54)>LSL 60101 [2-(2-benzofuranyl) imidazole] (75)>idazoxan (90)>LSL 60129 [2-(1,4-benzodioxan-6-yl)-4,5-dihydroimidazole](101)>RX82 1002 (2-methoxy idazoxan) (106)>agmatine (196). No neuroprotective effect of these drugs was observed in a model of apoptotic neuronal cell death (reduction of extracellular K+) which does not involve stimulation of NMDA receptors. Imidazol(ine) drugs and agmatine fully inhibited [3H]-(+)-MK-801 binding to the phencyclidine site of NMDA receptors in rat brain. The profile of drug potency protecting against L-glutamate neurotoxicity correlated well (r=0.90) with the potency of the same compounds competing against [3H]-(+)-MK-801 binding. In HEK-293 cells transfected to express the NR1-1a and NR2C subunits of the NMDA receptor, antazoline and agmatine produced a voltage- and concentration-dependent block of glutamate-induced currents. Analysis of the voltage dependence of the block was consistent with the presence of a binding site for antazoline located within the NMDA channel pore with an IC50 of 10-12 microM at 0 mV. It is concluded that imidazol(ine) drugs and agmatine are neuroprotective against glutamate-induced necrotic neuronal cell death in vitro and that this effect is mediated through NMDA receptor blockade by interacting with a site located within the NMDA channel pore.
Topics: Agmatine; Animals; Antazoline; Benzofurans; Cell Line; Cells, Cultured; Cerebellum; Dioxanes; Dizocilpine Maleate; Dose-Response Relationship, Drug; Electrophysiology; Glutamic Acid; Humans; Idazoxan; Imidazoles; Neuroprotective Agents; Patch-Clamp Techniques; Potassium; Radioligand Assay; Rats; Rats, Wistar; Receptors, N-Methyl-D-Aspartate; Styrenes
PubMed: 10455281
DOI: 10.1038/sj.bjp.0702679 -
Pharmacological Reports : PR 2005The aim of this study was to evaluate the effects of H(1) (antazoline and astemizole) or H(2) (cimetidine and famotidine) histamine receptor antagonists on the clonic...
The aim of this study was to evaluate the effects of H(1) (antazoline and astemizole) or H(2) (cimetidine and famotidine) histamine receptor antagonists on the clonic phase, tonic seizures and morality of mice challenged with aminophylline to induce convulsions in mice. Moreover, the total plasma and brain concentrations of theophylline were evaluated. Astemizole (1 mg/kg) did not affect the threshold for aminophylline-induced seizures, but when administered at a dose of 2 mg/kg, it significantly reduced the CD(50) value of aminophylline from 249 mg/kg to 211 mg/kg (p < 0.01). The remaining histamine receptor antagonists studied i.e., antazoline (up to 1 mg/kg), cimetidine (up to 40 mg/kg) and famotidine (up to 10 mg/kg) had no impact on seizure susceptibility in aminophylline-induced convulsions. Furthermore, astemizole (2 mg/kg) decreased latency to the clonic phase of aminophylline-induced convulsions from 51.1 +/- 4.5 to 32.1 +/- 4.3 min (p < 0.01). It is noteworthy that astemizole, a novel H(1) receptor antagonist, did not alter the brain and plasma levels of theophylline, so the existence of pharmacokinetic interactions was excluded. Our results indicate that some interactions between methylxanthines and histamine receptor antagonists may be clinically important since these drugs are usually combined during the treatment of status asthmaticus.
Topics: Aminophylline; Animals; Antazoline; Astemizole; Brain; Cimetidine; Dose-Response Relationship, Drug; Drug Interactions; Famotidine; Female; Histamine Antagonists; Mice; Seizures; Theophylline; Time Factors
PubMed: 16129921
DOI: No ID Found -
The American Journal of Cardiology Oct 1964
Topics: Antazoline; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Cardiac Complexes, Premature; Coronary Disease; Drug Therapy; Electrocardiography; Heart Diseases; Histamine H1 Antagonists; Humans; Procainamide; Quinidine; Rheumatic Heart Disease; Tachycardia; Tachycardia, Paroxysmal; Toxicology; Ventricular Fibrillation
PubMed: 14215062
DOI: 10.1016/0002-9149(64)90035-9 -
Acta Poloniae Pharmaceutica 2000Four drugs in the form of coated tablets: Amitryptylinum (Amitryptyline) (1), Imipramin (Imipramine) (2), Chloropyribenzaminum (Chloropyramine) (3), and Phenazolinum...
Four drugs in the form of coated tablets: Amitryptylinum (Amitryptyline) (1), Imipramin (Imipramine) (2), Chloropyribenzaminum (Chloropyramine) (3), and Phenazolinum (Antazoline) (4) were determined gravimetrically and spectrophotometrically in the same process by using complexes with ammonium molybdate. Stoichiometry of the complexes was established by elemental analysis and analysis of the incineration residue (MoO3). The complexes were characterized by IR and UV spectra and melting points. Contents of the drugs in the complexes were also determined spectrophotometrically. In this method Beer's law was found to obey over the concentration ranges 10-80 micrograms/ml (complex of 1), 10-100 micrograms/ml (complexes of 2 and 3), and 10-60 micrograms/ml (complex of 4). This method was validated in terms of precision, linearity, limit of detection and limit of quantitation. The two methods of the drug determination used in a single process of analysis, verify each other.
Topics: Amines; Chemical Phenomena; Chemistry, Physical; Spectrophotometry, Ultraviolet; Tablets, Enteric-Coated
PubMed: 10934785
DOI: No ID Found -
The Journal of the Royal College of... Jul 1987A series of comparative trials on nine popular and pharmacologically distinct regimens for the treatment of hay fever was undertaken in the course of normal general... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
A series of comparative trials on nine popular and pharmacologically distinct regimens for the treatment of hay fever was undertaken in the course of normal general practice in the pollen seasons of 1981-83. One hundred and forty doctors recruited 640 patients to assess the overall usefulness of the treatments on daily diaries. ;Usefulness' was scored on a linear analogue scale weighing up the degree of hay fever symptoms during treatment, side effects and ease of use of the preparation.The regimen with the highest overall usefulness score was beclomethasone diproprionate with sodium cromoglycate eye drops (Beconase and Opticrom). Although the score was not significantly higher than those for methylprednisolone acetate (Depo-Medrone), astemizole (Hismanal) or terfenadine (Triludan), Beconase/Opticrom scored significantly better than mequitazine (Primalan), chlorpheniramine maleate (Piriton), sodium cromoglycate nasal insufflation with xylometazoline/antazoline eye drops (Rynacrom and Otrivine-Antistin) and azatadine maleate (Optimine). Beconase/Opticrom was first in rank order with respect to all the other regimens for the treatment of both mild and severe hay fever. Dimethothiazine (Banistyl), also shown to be useful, has since been withdrawn from prescription.
Topics: Adolescent; Adult; Aged; Child; Cromolyn Sodium; Family Practice; Female; Histamine H1 Antagonists; Humans; Male; Middle Aged; Rhinitis, Allergic, Seasonal; Steroids; United Kingdom
PubMed: 2896796
DOI: No ID Found