Drugs online research references
Arch Neurol. 1986 Jul;43(7):687-9.
Attenuation of response to mental stress in patients with essential tremor treated with metoprolol.
Gengo FM, Kalonaros GC, McHugh WB.
The response to mental stress in patients with benign essential tremor is an exaggeration of the resting tremor. We have studied the ability of metoprolol tartrate to attenuate specifically the tremorgenic response to mental stress in five patients with essential tremor who were each studied on four occasions. Treatment regimens consisted of 0-, 25-, 50-, and 75-mg doses of metoprolol tartrate, given twice daily for seven- to ten-day periods. Tremor was measured while patients were resting comfortably and then again following mental stress over eight-hour study periods. During the baseline study period, the investigational mental stress consistently exaggerated tremor in each patient. Metoprolol treatment reduced both the resting tremor and tremor following mental activity, but the drug-induced change in the response to mental stress was more pronounced than the drug-induced reduction in resting tremor. The ability of metoprolol to blunt the response to mental stress was associated with serum concentrations of the drug. The time courses of metoprolol serum concentrations were similar to the time course of metoprolol's ability to blunt the response to mental stress. Metoprolol possesses the ability to blunt the tremorgenic response to mental stress in patients with essential tremor, but the duration of this effect lasts less than seven hours after administration of a dose.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3729747&dopt=Abstract
Circ Res. 1989 Nov;65(5):1417-25.
Significance of myocardial alpha- and beta-adrenoceptors in catecholamine-induced cardiac hypertrophy.
Zierhut W, Zimmer HG.
Department of Physiology, University of Munich, Munchen, FRG.
The role of alpha- and beta-adrenoceptors in the development of catecholamine-induced cardiac hypertrophy in vivo was investigated. Rats received a constant intravenous infusion of norepinephrine or sodium chloride (control) for 3 days. The norepinephrine infusion was combined with the alpha-blocker prazosin, the beta-blocker metoprolol, or both blockers. For modulation of the work load of the heart, the calcium channel blocker verapamil was added to the norepinephrine infusion. A further group of animals was treated with the alpha-adrenergic stimulator norfenephrine, which also was combined with prazosin or verapamil. Norepinephrine induced significant increases in mean aortic pressure, left ventricular dP/dtmax, heart rate, and total peripheral resistance. The left ventricular weight/body weight ratio was significantly elevated and was accompanied by an increase in the RNA concentration and the RNA/DNA ratio. Prazosin as well as metoprolol partially antagonized the increase in left ventricular weight and RNA concentration, whereas simultaneous prazosin and metoprolol treatment prevented the norepinephrine-induced alterations. Although combination of norepinephrine with verapamil resulted in considerable reduction of all functional parameters, the development of cardiac hypertrophy and the elevated RNA/DNA ratio were not significantly influenced. Stimulation of alpha-receptors with norfenephrine elicited an increase in total peripheral resistance and in left ventricular weight, which was abolished by prazosin. Verapamil did not affect the norfenephrine-induced cardiac hypertrophy, although it normalized essentially all functional parameters. Thus, the rapid development of cardiac hypertrophy in the norepinephrine model seems to be directly mediated by stimulation of myocardial alpha- and beta-adrenoceptors rather than by hemodynamic changes.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2572358&dopt=Abstract
Clin Pharmacol Ther. 1986 Oct;40(4):387-94.
Metoprolol and debrisoquin metabolism in Nigerians: lack of evidence for polymorphic oxidation.
Iyun AO, Lennard MS, Tucker GT, Woods HF.
The role of genetic polymorphism in the oxidative metabolism of metoprolol and debrisoquin was investigated in a population of 138 unrelated Nigerians. The debrisoquin/4-hydroxydebrisoquin 0-8 hour urinary ratio (D/HD) correlated significantly with the metoprolol/alpha-hydroxymetoprolol 0-8 hour urinary ratio (M/HM) (rs = 0.54; P less than 0.001), the metoprolol/H117-04 [4-(2-hydroxy-3-isopropylaminopropoxy)-phenylacetic acid] 0-8 hour urinary ratio (M/H117-04) (rs = 0.42; P less than 0.001), and the plasma metoprolol concentration at 3 hours (rs = 0.48; P less than 0.01). Both the median D/HD and M/HM ratios were significantly higher in this population than in a previously studied population of white British subjects. According to criteria established in studies of white populations, only one subject, later identified as an Indian, would be classified unequivocally as a poor metabolizer of both metoprolol and debrisoquin. All the other subjects were black Africans. Bimodality in the frequency distribution of both the log10 M/HM and D/HD ratios was not apparent. The poor hydroxylation trait may, therefore, be present at a lower frequency than in whites, absent altogether, or obscured by other factors. In ethnic studies of drug metabolism each racial group should be examined separately for evidence of polymorphic metabolism and antimodes should not be extrapolated from one population to another.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3757401&dopt=Abstract
online pharmacies ||
Hair Million herbal formula for hair loss and hair growth ||
Amoxicillin ||
Tramadol ||
Paxil ||
Rx Drugs USA, Prescription Drugs Online Pharmacy ||
Zithromax ||
online pharmacy ||
Antibiotics and prescription medications online literature ||
Antibiotics