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British Journal of Clinical Pharmacology Feb 19801 Thirteen hypertensive patients completed a double-blind comparison of placebo, acebutolol 200 mg twice daily and acebutolol 400 mg once daily, administered for 4 weeks... (Clinical Trial)
Clinical Trial Comparative Study Randomized Controlled Trial
1 Thirteen hypertensive patients completed a double-blind comparison of placebo, acebutolol 200 mg twice daily and acebutolol 400 mg once daily, administered for 4 weeks in random order. 2 Blood pressure and heart rate were significantly reduced by both acebutolol treatments. The mean reduction of resting pressure 12 h after 200 mg twice daily (12/7 mmHg) was similar to that 24 hr after 400 mg once daily (13/9 mmHg). 3 Compared to placebo, reductions in exercise heart rate and systolic pressure at 12 h after 200 mg twice daily and 24 h after 400 mg once daily were significant and similar. 4 Beta-adrenoceptor antagonism was also assessed by inhibition of the heart rate response to sublingual glyceryl trinitrate taken in the standing position. Both acebutolol treatments reduced the response; the reduction after twice daily treatment (mean 25 beats/min) was significantly greater than after once daily treatment (mean 19 beats/min). 5 There was no difference in blood pressure control between acebutolol administered once and twice daily in a total daily dose of 400 mg.
Topics: Acebutolol; Adult; Blood Pressure; Double-Blind Method; Drug Administration Schedule; Female; Heart Rate; Humans; Hypertension; Male; Middle Aged; Nitroglycerin; Patient Compliance
PubMed: 6766731
DOI: 10.1111/j.1365-2125.1980.tb05835.x -
British Journal of Clinical Pharmacology 1984Higher AUC and Cmax values were obtained for metoprolol, oxprenolol and propranolol in groups receiving the low-dose oestrogen-ethinyl oestradiol oral contraceptive, but...
Higher AUC and Cmax values were obtained for metoprolol, oxprenolol and propranolol in groups receiving the low-dose oestrogen-ethinyl oestradiol oral contraceptive, but statistical significance was reached only with metoprolol AUC. The oral contraceptive had the opposite effect on acebutolol AUC and Cmax but this was not significant. The oral contraceptive had no detectable effects on the tmax and t 1/2 values of any of the beta-adrenoceptor blockers.
Topics: Acebutolol; Adrenergic beta-Antagonists; Contraceptives, Oral; Contraceptives, Oral, Hormonal; Drug Interactions; Female; Humans; Kinetics; Metoprolol; Oxprenolol; Propranolol; Time Factors
PubMed: 6146344
DOI: 10.1111/j.1365-2125.1984.tb02435.x -
Scientific Reports Jan 2019In the present study, we measured the spontaneous post synaptic currents (sPSCs) at the post synaptic principle cells of the medial nucleus of the trapezoid body (MNTB)...
In the present study, we measured the spontaneous post synaptic currents (sPSCs) at the post synaptic principle cells of the medial nucleus of the trapezoid body (MNTB) in early postnatal mice after exposure to 1850 MHz radiofrequency electromagnetic fields (RF-EMF). sPSC frequencies and amplitudes were significantly increased in the RF-EMF exposed group. Moreover, the number of synaptic vesicles in the calyx of Held was significantly increased in presynaptic nerve terminals. Following RF-EMF exposure, the number of docking synaptic vesicles in the active zone increased, thereby expanding the total length of the presynaptic active zone in the calyx of Held. These data suggest that the increased sPSCs are a result of greater synaptic vesicle release from presynaptic nerves. However, we found no morphological changes in the inner hair cell ribbon synapses. Further, there were no significant changes in the hearing threshold of the auditory brainstem response at postnatal day 15. Our results indicate that exposure to RF-EMF at an early postnatal stage might directly affect brainstem auditory circuits, but it does not seem to alter general sound perception.
Topics: Acebutolol; Animals; Animals, Newborn; Evoked Potentials, Auditory, Brain Stem; Mice, Inbred ICR; Radio Waves; Synaptic Transmission; Synaptic Vesicles; Trapezoid Body
PubMed: 30674958
DOI: 10.1038/s41598-018-36868-1 -
British Journal of Pharmacology May 19931. The effects of tienoxolol, (ethyl 2-[3-[(1,1-dimethylethyl)amino]-2-hydroxypropoxy]-5- [(2-thienylcarbonyl) amino] benzoate, hydrochloride), a novel drug exhibiting...
1. The effects of tienoxolol, (ethyl 2-[3-[(1,1-dimethylethyl)amino]-2-hydroxypropoxy]-5- [(2-thienylcarbonyl) amino] benzoate, hydrochloride), a novel drug exhibiting both diuretic and beta-adrenoceptor blocking properties, were investigated on urinary 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) and PGE2 excretion in the rat and compared to those of reference diuretic (furosemide) and beta-adrenoceptor antagonists (acebutolol, propranolol). Since tienoxolol was shown to bind to A1 and A2 adenosine receptors, the action of theophylline was also evaluated. 2. Tienoxolol (8-128 mg kg-1, p.o.) induced a dose-related increase of 6-keto-PGF1 alpha excretion from 32 mg kg-1 but a significant elevation of urinary PGE2 levels was only reached after administration of 128 mg kg-1. However, renal prostaglandin concentrations were not modified by tienoxolol. 3. Furosemide (32 mg kg-1) displayed a strong diuretic activity but did not enhance 6-keto-PGF1 alpha excretion. Likewise, the latter was unaffected by acebutolol and propranolol (128 mg kg-1) and no significant diuresis was observed following administration of these two beta-blocking agents. Theophylline (64 mg kg-1), like tienoxolol, was able to induce both diuresis and urinary prostaglandin excretion. Furthermore, they bound with similar affinities to A1 and A2 adenosine receptors. This led to the suggestion that a relationship between P1-purinoceptors, prostaglandin release, diuresis and natriuresis could exist. 4. Oral co-administration of NECA (0.2 mg kg-1) with tienoxolol markedly reduced the urinary 6-keto-PGF1 alpha excretion observed when tienoxolol was administered alone. However, neither diuresis nor natriuresis were modified, demonstrating that the proposed relationship was untenable. 5. In conclusion, PGI2 probably does not participate in the diuretic and natriuretic activity oftienoxolol. The increase of urinary 6-keto-PGF1alpha excretion may result not only from the haemodynamic properties of the drug but also from the rise of the urinary flow induced by tienoxolol.
Topics: 6-Ketoprostaglandin F1 alpha; Adenosine; Adenosine-5'-(N-ethylcarboxamide); Adrenergic beta-Antagonists; Animals; Brain Chemistry; Dinoprostone; Diuresis; Epoprostenol; Furosemide; Male; Natriuresis; Propanolamines; Prostaglandins; Radioimmunoassay; Radioligand Assay; Rats; Rats, Inbred Strains; Receptors, Purinergic; Theophylline; Vasodilator Agents
PubMed: 8098641
DOI: 10.1111/j.1476-5381.1993.tb13565.x -
American Journal of Botany Jul 2013Global change requires plant ecologists to predict future states of biological diversity to aid the management of natural communities, thus introducing a number of...
Global change requires plant ecologists to predict future states of biological diversity to aid the management of natural communities, thus introducing a number of significant challenges. One major challenge is considering how the many interacting features of biological systems, including ecophysiological processes, plant life histories, and species interactions, relate to performance in the face of a changing environment. We have employed a functional trait approach to understand the individual, population, and community dynamics of a model system of Sonoran Desert winter annual plants. We have used a comprehensive approach that connects physiological ecology and comparative biology to population and community dynamics, while emphasizing both ecological and evolutionary processes. This approach has led to a fairly robust understanding of past and contemporary dynamics in response to changes in climate. In this community, there is striking variation in physiological and demographic responses to both precipitation and temperature that is described by a trade-off between water-use efficiency (WUE) and relative growth rate (RGR). This community-wide trade-off predicts both the demographic and life history variation that contribute to species coexistence. Our framework has provided a mechanistic explanation to the recent warming, drying, and climate variability that has driven a surprising shift in these communities: cold-adapted species with more buffered population dynamics have increased in relative abundance. These types of comprehensive approaches that acknowledge the hierarchical nature of biology may be especially useful in aiding prediction. The emerging, novel and nonstationary climate constrains our use of simplistic statistical representations of past plant behavior in predicting the future, without understanding the mechanistic basis of change.
Topics: Acebutolol; Climate Change; Desert Climate; Ecosystem; Environmental Monitoring; Photosynthesis; Plant Physiological Phenomena; Plants; Population Dynamics; Seasons
PubMed: 23838034
DOI: 10.3732/ajb.1200463 -
British Journal of Pharmacology Jun 19991. Negative inotropic effects of several beta-adrenoceptor (betaAR) antagonists on electrically-stimulated right atria, left atria, right ventricles and left ventricular...
1. Negative inotropic effects of several beta-adrenoceptor (betaAR) antagonists on electrically-stimulated right atria, left atria, right ventricles and left ventricular papillary muscles from reserpine-treated rats were used as a measure of their inverse agonist activities. 2. Beta1AR antagonists acebutolol, atenolol and metoprolol, beta2AR antagonist ICI-181,551 and nonselective betaAR antagonists alprenolol, nadolol, propranolol and timolol produced negative inotropic effects, which were most marked on the right atria. 3. The nonselective betaAR antagonist pindolol did not exhibit inverse agonist activity but inhibited the negative inotropic activities of ICI-118,551, atenolol and propranolol. 4. The negative inotropic effects of lidocaine, nifedipine and pentobarbitone were similar on all the four myocardial preparations. 5. The positive inotropic efficacy of salbutamol on right and left atria but not on right ventricles and papillary muscles was comparable to that of isoprenaline. The antagonist activity of ICI-118,551 against isoprenaline was greater on right atria than on other cardiac regions. 6. Beta1AR proteins were expressed in all regions of the heart but of beta2AR were primarily localized in the right atrium. 7. It is concluded that beta2AR play a greater role in right atria than in other cardiac regions and almost all betaAR antagonists behave as inverse agonists.
Topics: Adrenergic beta-Agonists; Adrenergic beta-Antagonists; Albuterol; Animals; Blotting, Western; In Vitro Techniques; Isoproterenol; Male; Myocardial Contraction; Pindolol; Propanolamines; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, beta-1; Receptors, Adrenergic, beta-2
PubMed: 10433496
DOI: 10.1038/sj.bjp.0702616 -
British Journal of Clinical Pharmacology Sep 1980
Topics: Acebutolol; Antibodies, Antinuclear; Humans
PubMed: 6969082
DOI: 10.1111/j.1365-2125.1980.tb01765.x -
British Medical Journal Aug 1978Atenolol was compared with five other beta-blockers and a thiazide diuretic in a randomised cross-over trial of once-daily treatment of essential hypertension. Atenolol... (Clinical Trial)
Clinical Trial Comparative Study Randomized Controlled Trial
Atenolol was compared with five other beta-blockers and a thiazide diuretic in a randomised cross-over trial of once-daily treatment of essential hypertension. Atenolol was significantly better at reducing resting and exercise blood pressures at 24 hours than any of the other drugs and had a low incidence of side effects. Both timolol and acebutolol had a significant hypotensive effect at 24 hours and a low incidence of side effects, suggesting that further increases in dosage might be effective and well tolerated. Labetalol proved ineffective when given once daily, and the high incidence of side effects, equalled only by pindolol, would probably prohibit further increases in dosage. Bendrofluazide was equal or superior to all the beta-blockers except atenolol at reducing resting blood pressure, and its cheapness still makes it an agent of first choice in mild or moderate essential hypertension.
Topics: Acebutolol; Adrenergic beta-Antagonists; Adult; Atenolol; Bendroflumethiazide; Clinical Trials as Topic; Female; Humans; Hypertension; Labetalol; Male; Middle Aged; Pindolol; Propranolol; Random Allocation; Timolol
PubMed: 28810
DOI: 10.1136/bmj.2.6134.383 -
British Journal of Clinical Pharmacology Sep 1981
Topics: Acebutolol; Adult; Female; Humans; Male; Middle Aged; Saliva
PubMed: 7295474
DOI: 10.1111/j.1365-2125.1981.tb01239.x -
Ultrasonics Sonochemistry Sep 2019This study mainly covered the cavitation erosion in probe sonication and its electrochemical behavior. The activated graphite was exfoliated by the probe sonication...
This study mainly covered the cavitation erosion in probe sonication and its electrochemical behavior. The activated graphite was exfoliated by the probe sonication wherein the titanium alloy (TA) is used as a probe (micro-tip). The sonication performed in the aqueous solution contains a mixture of sulfuric acid and nitric acid (1:1). The exfoliated graphite (EG) was examined by field emission scanning electron microscope, Raman and X-ray diffraction pattern analysis. The results showed that some TA particles dissolute from the TA micro-tip accompanied with graphite exfoliation. This dissolution experienced from the cavitation erosion, because the acoustic cavitation makes severe deformation on probe tips due to the bubble collapse. The dissolution rate increased when increasing sonication time; the resultant TA particles are randomly distributed over the EG. These EGTAs applied to the electrochemical oxidation of acebutolol which revealed an appreciable electrochemical performance and also exhibited better analytical performances to the electrochemical determinations. The obtained analytical parameters viz., sensitivity (0.234 µA µM cm), linear range (0.01-15.1 µM), and limit of detection (0.003 µM) are highly comparable with the previous reports. Moreover, it has an acceptable tolerance with the interfering substances.
PubMed: 31101266
DOI: 10.1016/j.ultsonch.2019.04.025