Search results for "Propanolamines"
showing 10 items of 23 documents
Selective downregulation of the MDR1 gene product in Caco-2 cells by stable transfection to prove its relevance in secretory drug transport.
2005
Considerable interest is focused on overcoming multidrug resistance (MDR) in cancer chemotherapy. The in vitro experiments to characterize P-glycoprotein's (P-gp) function and to decrease its effects have led to a variety of strategies such as addition of competitors or supplementation of the medium with oligonucleotides complementary to the 5'-end of the MDR1-mRNA. For the Caco-2 cell line, an in vitro model for absorption screening, expressing multiple transporters including P-gp, which pumps substances back into the apical solution, P-gp activity might mask other relevant transport proteins' activity. The objective of the present study was to construct a Caco-2 subline with reduced P-gp …
Effect of single-dose and short-term administration of quercetin on the pharmacokinetics of talinolol in humans – Implications for the evaluation of …
2013
Quercetin has been shown to inhibit intestinal P-glycoprotein-mediated drug efflux. A crossover clinical study was performed in 10 healthy volunteers to assess the effect of single-dose and repeated quercetin intake on the pharmacokinetics of talinolol, a substrate of intestinal P-glycoprotein. Unexpectedly, mean area under the plasma concentration-time curve (AUC0-48h) and maximal plasma concentration (cmax) were slightly decreased following concomitant and short-term quercetin administration (3186.0 versus 2468.3 and 2527.7 ng h/ml, p>0.05; 309.7 versus 212.0 and 280.6 ng/ml, p>0.05). Individual analysis revealed that talinolol AUC0-48h was lowered by 23.9% up to 60.6% in 5 subjects and c…
Effects of controlled-release on the pharmacokinetics and absorption characteristics of a compound undergoing intestinal efflux in humans
2006
Abstract Objective The number of active pharmaceutical ingredients (API) undergoing inhibitable and saturable intestinal efflux is considerable. As a consequence, absorption and bioavailability may depend on the intestinal concentration profile of the drug and may vary as a function of dose and release rate of the drug from the dosage form. The impact of controlled versus immediate-release on the absorption of P-glycoprotein substrates is currently unknown. Thus, the main focus of the present study was a comparison of the pharmacokinetics of the P-gp model substrate talinolol following administration of immediate-release (IR) and controlled-release (CR) tablets to healthy human volunteers w…
The use of esmolol in whole-body hyperthermia: Cardiovascular effects
1997
Whole-body hyperthermia (WBH) is a well-described investigational adjunct to systemic chemotherapy for the treatment of advanced malignancies. The hemodynamic consequences of this physiologic state may include tachycardia, which can produce acute myocardial ischemia in patients with coronary artery disease. Ischemic heart disease is currently considered a contraindication to WBH. We chose to investigate the consequences of using a new beta 1-adrenergic antagonist, esmolol, to attempt to control the tachycardia associated with WBH. After institutional approval and patient consent, nine consecutive patients with normal cardiac function presenting for WBH with carboplatin infusion were studied…
Atenolol interaction with aspirin, allopurinol, and ampicillin.
1983
Atenolol kinetics were investigated in six healthy subjects after 100 mg orally, as monotherapy a 6-day treatment began 48 hr later. After a therapy-free interval of 4 wk, the same subjects received the same dose of atenolol with 1 gm ampicillin, 500 mg aspirin, and with 300 mg allopurinol. Allopurinol and aspirin did not substantially alter the kinetics of atenolol. After a single oral dose of 100 mg atenolol combined with 1 gm ampicillin, the bioavailability of atenolol was reduced to 36 +/- 5% compared to 60 +/- 8% after monotherapy. During long-term treatment with atenolol and ampicillin the bioavailability of atenolol fell to 24% (P less than 0.01). Mean peak plasma levels were lowered…
[Validity of the use of penbutolol in essential arterial hypertension].
1990
Thirty patients suffering from WHO I-II class slight-moderate essential arterial hypertension were treated with a beta-blocker (Penbutolol) alone and once a day to assess its antihypertensive effectiveness and its affect on heart frequency, lipid metabolism and kidney function. The drug proved highly effective in reducing P.A.S. and P.A.D. values and no negative influence was documented on lipid metabolism, kidney function or heart frequency.
Interaction of atenolol with furosemide and calcium and aluminum salts
1981
Six healthy subjects were treated with 100 mg atenolol. After a therapy-free interval of 4 wk the same subjects received the same dose of atenolol with furosemide, 40 mg, with calcium (as the lactate gluconate and carbonate), 500 mg, or with aluminum hydroxide, 5.6 gm. Atenolol alone and in combination was administered first as a single oral dose; a long-term 6-day treatment began 48 hr later. Addition of furosemide did not influence atenolol kinetics, but aluminum hydroxide led to an insignificant reduction (P greater than 0.05) of mean peak plasma levels of about 20% and of the area under the plasma concentration-time curve (AUC -infinity) from 5818 to 4353 ng ml-1 hr (P greater than 0.05…
High-dose short-term administration of naringin did not alter talinolol pharmacokinetics in humans.
2015
Naringin is considered the major causative ingredient of the inhibition of intestinal drug uptake by grapefruit juice. Moreover, it is contained in highly dosed nutraceuticals available on the market. A controlled, open, randomized, crossover study was performed in 10 healthy volunteers to investigate the effect of high-dose naringin on the bioavailability of talinolol, a substrate of intestinal organic anion-transporting polypeptide (OATP)-mediated uptake. Following 6-day supplementation with 3 capsules of 350 mg naringin daily, 100mg talinolol were administered orally with 3 capsules of the same dietary supplement (1050 mg naringin) on the seventh day. This test treatment was compared to …
Effects of Nebivolol versus Carvedilol on Left Ventricular Function in Patients with Chronic Heart Failure and Reduced Left Ventricular Systolic Func…
2006
Beta-adrenoceptor antagonist (beta-blocker) therapy results in a significant improvement in left ventricular (LV) systolic function and prognosis in patients with chronic heart failure. Both carvedilol and nebivolol produce hemodynamic and clinical benefits in chronic heart failure, but it is unknown whether their peculiar pharmacologic properties produce different effects on LV function.To assess the effects on LV function of nebivolol compared with carvedilol in patients with chronic heart failure and reduced LV systolic function.Seventy patients with a LV ejection fractionor=40% and in New York Heart Association (NYHA) functional class II or III were randomly assigned to receive carvedil…
Pharmacokinetics of atenolol in relation to renal function
1981
The plasma levels and urinary excretion of carteolol and its main metabolites 8-hydroxycarteolol and carteolol glucuronide were investigated in 6 healthy subjects and 9 patients with varying degrees of renal impairment following a single oral dose of 30 mg carteolol hydrochloride. In healthy subjects the half-life of carteolol was 7.1 h. 63% of the administered dose was recovered unchanged in urine, and in all 84% was excreted by the kidneys. The renal clearance of carteolol was 255 ml/min. In chronic renal failure (CRF) the terminal half-life was increased to a maximum of 41 h. Both the elimination rate constant and renal clearance were closely related to the creatinine clearance. In CRF t…