Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    European journal of clinical pharmacology 44 (1993), S. 489-492 
    ISSN: 1432-1041
    Keywords: Chronopharmacology ; Propranolol ; absorption ; age
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary There is diurnal variation in the absorption rate of propranolol in younger subjects. This study was undertaken to examine the effect of age on the chronopharmacokinetics of propranolol. We gave 20 mg of propranolol orally to 13 younger and 11 older hypertensive subjects at 09.00 h (day study) or 21.00 h (night study) in a cross-over design. Plasma concentrations of propranolol and its metabolites, 4-hydroxypropranolol and naphthoxylactic acid, were determined just before and at 0.5, 1, 1.5, 2, 3, 4, 6, 12, and 24 h after dosage. In the younger subjects the absorption rate constant (ka) of propranolol and its maximum plasma concentration (Cmax) were significantly higher and the time to maximum concentration (tmax) was significantly shorter in the day than at night. There were similar time-variant changes in Cmax and tmax for 4-hydroxypropranolol and naphthoxylactic acid. In contrast, there were no time-variant changes in ka, Cmax and tmax of propranolol and its metabolites in the older subjects. These results suggest that propranolol is absorbed more rapidly after morning dosing than after night-time dosing in younger but not in older subjects. Based on these findings, we speculate that the time-variance in the absorption rate or first-pass elimination, or both, of propranolol diminish with age.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    European journal of clinical pharmacology 39 (1990), S. 113-115 
    ISSN: 1432-1041
    Keywords: Furosemide ; 6-keto-PGF1α ; hypertension ; angiotensin II ; captopril ; urinary PGs ; PGI2
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The role of angiotensin II (AII) in Prostaglandin I2 (PGI2) production following furosemide has been examined in a placebo-controlled, cross-over study. Furosemide 20 mg was injected intravenously in eight hypertensive subjects already treated with oral captopril 25 mg or a matching placebo. Urinary excretion of 6-keto-PGF1α (a metabolite of PGI2) and PGE2, PRA and AII was increased following furosemide without captopril pretreatment. The rises in urinary 6-keto-PGF1α and PGE2, and plasma AII after furosemide were prevented by the captopril pretreatment. Urinary volume, sodium and furosemide were not affected by captopril. The data indicate that the effect of furosemide on PGI2 production, as reflected by the urinary excretion of 6-keto-PGF1α, was mediated by an action of AII.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    European journal of clinical pharmacology 43 (1992), S. 299-301 
    ISSN: 1432-1041
    Keywords: Probucol ; elevated cholesterol, chronopharmacology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary A time-dependent change in the cholesterol-lowering effect of probucol has been evaluated in 20 subjects with elevated cholesterol. Probucol 500 mg was given once daily at 07.00 h (day trial) or 19.00 h (night trial) for 3 months according to a crossover design. Fasting blood samples were obtained during the control period and at the end of each treatment period. Serum concentrations of total and HDL-cholesterol were significantly decreased by both the treatments with probucol [total cholesterol (mmol · l−1): control 6.58; day trial 5.41; night trial 5.10; HDL-cholesterol (mmol · l−1): control 1.35; day trial 1.06; night trial 0.96]. These parameters were significantly lower in the night trial than in the day trial. The data indicate that the cholesterol-lowering effect of probucol varies with its time of administration in subjects with elevated cholesterol.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-1041
    Keywords: propranolol ; chronopharmacology ; exercise-induced tachycardia ; pharmacokinetics ; healthy volunteers ; gastio-intestinal absorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Following a cross-over design propranolol 20 mg p.o. was given to 7 healthy subjects at 09.00 h and 21.00 h at an interval of 1 week. Heart rate (HR) during submaximal ergometer exercise was measured at four intervals during 10 h after treatment. Plasma propranolol concentrations were also determined. The suppressive effect (%R) of propranolol on the rise in HR during exercise after the morning dosage was significantly greater at 1.5 h and tended to be greater 3 h after administration than at comparable times in the evening trial. Mean plasma propranolol concentrations during the early phase were higher after the morning than the evening dose. The maximum plasma concentration (Cmax), area under the plasma concentration-time curve from 0 to 10 h (AUC (0–10)) and absorption rate constant (ka) were significantly greater after the morning dose. The time to maximum concentration (tmax) and elimination half-life (t1/2) of the morning and evening dosages did not differ. A significant correlation was observed between plasma propranolol concentration and %R in HR during exercise in the morning (r=0.74) and evening (r=0.63) trials, and the regression lines of the morning and evening treatments did not differ. The data indicate that the suppressive effect of propranolol on exercise-induced tachycardia was relatively greater after a morning than an evening dose; that propranolol was more rapidly absorbed from the gastrointestinal tract after the morning than the evening dosage; that diurnal changes in the activity of propranolol depend in part on the time of administration and its subsequent effect on plasma concentrations of the drug; and that the antagonist activity of propranolol relative to a given drug concentration may not differ between morning and evening treatments.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    European journal of clinical pharmacology 43 (1992), S. 501-505 
    ISSN: 1432-1041
    Keywords: S-1452 ; thromboxane A2 receptor antagonist ; nocturnal dosage ; platelet aggregation ; circadian rhythm ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary It is well known that platelet aggregation shows a morning rise, which may contribute to the increase in the onset of ischaemic heart diseases during the morning period. The present study was undertaken to determine whether nocturnal dosage with S-1452, a thromboxane AZ receptor antagonist, would blunt the morning rise in platelet aggregability. S-1452 50 mg or placebo were given orally to 8 healthy subjects at 10.00 h (day trial) or 22.00 h (night trial) according to a cross-over design. Plasma concentrations of S-1452 and its metabolites, bisnor-( + )-S-145 and tetranor-(+ )-S-145, and platelet aggregation were determined during the 12-hour period following the dose. Mean plasma concentrations of S-1452, bisnor-( + )-S-145 and tetranor-(+ )-S-145 during the absorption phase were lower after the nocturnal dose than after the morning dose. The maximum plasma concentration and area under the plasma concentration-time curve of the compounds were also lower and the time to the maximum concentration were delayed after the treatment at night. A morning rise in platelet aggregation was observed following placebo treatment. The inhibitory effect of S-1452 on platelet aggregation was observed at 3 hours and persisted for up to 9 h in both trials. The results suggest that S-1452 is absorbed more slowly after the nocturnal dose than after the morning dose. However nocturnal treatment with 50 mg S-1452 may blunt the morning rise in platelet aggregability.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    European journal of clinical pharmacology 46 (1994), S. 267-269 
    ISSN: 1432-1041
    Keywords: Lomefloxacin ; Furosemide ; Renal clearance ; drug interaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Abstract The interaction between lomefloxacin, a new quinolone, and furosemide, a loop diuretic, has been examined. Oral lomefloxacin 200 mg and furosemide 40 mg were given together or separately to 8 healthy subjects, and blood and urine samples were obtained over the following 12 h. The plasma concentrations of lomefloxacin following coadministration with furosemide were higher than after lomefloxacin alone and its AUC was increased, and its total and renal clearances were decreased. No change in the pharmacokinetics of furosemide was found after coadministration of lomefloxacin. As quinolones and furosemide are reported to be excreted in urine by the renal tubular anion transport system, the present results suggest that the renal tubular secretion of lomefloxacin is diminished by furosemide. It is not clear whether this pharmacokinetic interaction might be clinically important.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Annals of biomedical engineering 22 (1994), S. 532-539 
    ISSN: 1573-9686
    Keywords: Osteoporosis ; Trabecular structure ; Bone metabolism ; Femoral neck fracture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract Progression of osteoporosis is caused by a decline in bone formation activity relative to the resorption activity. In this paper, the authors carried out a theoretical analysis of the progression of osteoporosis to estimate the osteoporotic change in the upper end of the femur. According to this analysis, the progression rate of osteoporosis in cancellous bone depends on the product of remodeling activity,R act, and the trabecular structure parameter,K tr. To confirm that the theoretical results were reasonably comparable to actual osteoporotic change, these two factors were measured in rabbits. From the results, it was concluded that the highest progression rate was shown in bar/barlike trabecular structure (type 3); the next highest rate, was shown in plate/bar-like structure (type 2); and the plate/plate-like structure (type 1) was the most insensible. Furthermore, the bone volume fractions of cancellous bone were measured at the upper end of human femurs with and without osteoporosis. Then the measured value was compared with the theoretical value for each type of trabecular structure. Results showed that the decrease in bone volume fraction predicted by Eq. 7 was well in accord with the actual decrease.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...