Biomaterial Database

Urinary metabolites of caffeine in young dogs. 1982

D Warszawski, and Z Ben-Zvi, and R Gorodischer, and M J Arnaud, and I Bracco

Urinary elimination of [1-methyl-14C]caffeine was investigated in young dogs. Mongrel dogs aged 2 days, 1 week, and 5 weeks received single doses of caffeine (50 mg/kg) through an orogastric tube. Eight dogs, each studied once, were involved. At identical times after the dose the ratio of urinary caffeine metabolites to unchanged caffeine was greatest in the 5-week-old and smallest in the 2-day-old puppy; cumulative ratios at (or very close to) the plateau of urinary excretion varied between 8.7 and 17.8 in the 5-week-old, 3.6 and 3.8 in the 1-week-old, and 2.2 and 2.4 in the 2-day-old dogs. The time needed to reach the plateau of the cumulative excretion of radioactivity in the urine decreased with age. Initially only caffeine was detected in the urine of the 2-day-old and 1-week-old dogs; the first quantitatively important metabolites were trimethyluric acid and 6-amino-5-(N-methylformylamino)-1,3 dimethyluracil (also known as 1,3,7-trimethyldihydrouric acid) in the 2-day-old, and the uracil derivative and theophylline in the 1-week-old and the 5-week-old puppies. The percentage of demethylated uric acid metabolites and uracil derivatives increased progressively with increasing age; this indicates increased demethylation, oxidation to uric acids and hydrolysis of the imidazole ring of caffeine with increasing age. These results are consistent with the previously reported slow plasma elimination of caffeine in the newborn and confirm the limited capacity of the young (as compared to the adult) mammal to metabolize caffeine.

UI	MeSH Term	Description	Entries
D008297	Male		Males
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
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D005260	Female		Females
D000367	Age Factors	Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.	Age Reporting,Age Factor,Factor, Age,Factors, Age
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000831	Animals, Newborn	Refers to animals in the period of time just after birth.	Animals, Neonatal,Animal, Neonatal,Animal, Newborn,Neonatal Animal,Neonatal Animals,Newborn Animal,Newborn Animals
D001711	Biotransformation	The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.