Biomaterial Database

Relationship between total body clearance of caffeine and urine flow rate in elderly men. 1985

J M Trang, and J Blanchard, and K A Conrad, and G G Harrison

The total body clearance (CL), renal clearance (CLR), and nonrenal clearance (CLNR) of caffeine from plasma were determined following the intravenous administration of caffeine (4 mg kg-1) to ten healthy men (aged 66-86 years) on three separate occasions. Positive correlations were observed between CL and urine flow rate (UFR), between CLR and UFR, and between CLNR and UFR (r = 0.8947, p = 0.0002; r = 0.8832, p = 0.0003; and r = 0.8920, p = 0.0002, respectively). Previous studies have established similar relationships between CLR and UFR for caffeine and its initial dimethylxanthine metabolites; theophylline, theobromine, and paraxanthine. A relationship between CL and UFR has not been reported previously.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D008297	Male		Males
D008657	Metabolic Clearance Rate	Volume of biological fluid completely cleared of drug metabolites as measured in unit time. Elimination occurs as a result of metabolic processes in the kidney, liver, saliva, sweat, intestine, heart, brain, or other site.	Total Body Clearance Rate,Clearance Rate, Metabolic,Clearance Rates, Metabolic,Metabolic Clearance Rates,Rate, Metabolic Clearance,Rates, Metabolic Clearance
D002110	Caffeine	A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.	1,3,7-Trimethylxanthine,Caffedrine,Coffeinum N,Coffeinum Purrum,Dexitac,Durvitan,No Doz,Percoffedrinol N,Percutaféine,Quick-Pep,Vivarin,Quick Pep,QuickPep
D004231	Diuresis	An increase in the excretion of URINE. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Diureses
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000368	Aged	A person 65 years of age or older. For a person older than 79 years, AGED, 80 AND OVER is available.	Elderly