Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: KEGG:D01453 (caffeine)
 21,611 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Experiments were made to determine whether cyclic AMP plays a role in transmission at identified dopaminergic synapses in the water snail Planorbis corneus. Intracellular stimulation of a specific dopamine neuron produces direct inhibitory postsynaptic potentials (ipsps) in a number of other neurons. These ipsps, which are mediated by dopamine, were potentiated by as much as 120% by caffeine, theophylline or dibutyryl cyclic AMP, although they were unaffected by cyclic AMP and prostaglandin E1. Caffeine and theophylline also potentiated the inhibitory response to dopamine, applied to the postsynaptic neurons by perfusion or iontophoresis, but the effects were generally much smaller (maximum potentiation 30%). The results provide evidence that postsynaptic cyclic AMP is involved in transmission at these synapses, but that the phosphodiesterase inhibitors may also have a presynaptic effect.
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PMID:Potentiation of dopaminergic transmission by phosphodiesterase inhibitors and cyclic nucleotides. 1 61

In the course of examining the complete dose-response relationship for the behavioral effects of LSD in the cat, we discovered that, in addition to large increases in investigatory and hallucinatory-like responses, two behaviors, not previously reported, are emitted with a high probability under LSD. Beginning from a baseline of essentially zero in saline-treated animals, limb flicks and abortive grooming increase in frequency in direct relation to the dose of LSD administered (2.5, 10, 25 and 50 microgram/kg i.p.) and then decrease at higher doses (100 and 200 microgram/kg). Limb flicks are a species-specific behavior seen in normal cats almost exclusively in response to the presence of a foreign substance, such as water, on the hindpaw or forepaw. In abortive grooming, the cat orients to the body surfaces as if to groom but does not emit the consummatory grooming response (bite, lick or scratch), or emits the response in midair. These behaviors can serve as an animal behavior model for the actions of LSD and related hallucinogens in humans. The specificity of these behavioral changes is indicated by the fact that they are never seen in response to other classes of psychoactive drugs such as D-amphetamine, atropine, caffeine, and cholorpheniramine. They are, however, elicited by compounds such as psilocybin which are structurally and functionally related to LSD. The validity of the model is based on evidence indicating that it is: specific to hallucinogens, dose dependent, observed in a dose range effective in humans, parallels the major parameters of the actions of LSD in humans (see following paper), sensitive, robust, reliable, quantifiable and easy to score.
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PMID:Behavioral effects of LSD in the cat: proposal of an animal behavior model for studying the actions of hallucinogenic drugs. 1 28

The dissolution rate of compressed salicylamide discs has been measured in water and in caffeine solutions of increasing concentration at 15, 25, 37 and 45 degrees in an apparatus rotating at 48 rev min-1 or more. Dissolution rate profiles showed breaks indicative of a shift in the mechanism of dissolution from interfacial towards transport control. The shifts occurred at higher caffeine concentrations on increasing the agitation rate or temperature. The dependencies of dissolution rates on agitation rates typified the intermediate type of dissolution and Arrhenius plots indicated that interfacial and transport processes participated in salicylamide dissolution.
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PMID:The dissolution mechanism in a system undergoing complexation: salicylamide in caffeine solution. 2 Dec 54

In a 13-night sleep laboratory study, each of 18 normal young adult males twice received 1 cup of warm water, 1-, 2-, and 4-cup equivalents of regular coffee, a 4-cup equivalent of decaffeinated coffee, and a 4-cup equivalent of caffeine. All beverages were administered 30 min before bedtime according to a balanced Latin-square design. Regular coffee produced dose-related changes in most standard electroencephalogram-electrooculogram (EEG-EOG) sleep parameters, and the 4-cup equivalents of regular coffee and caffeine produced equivalent effects. Decaffeinated coffee had no effect. Regular coffee and caffeine caused rapid eye movement (REM) sleep to shift to the early part of the night and stages 3 and 4 sleep to shift to the later part. Coffee also produced dose-related changes in several subjects estimates of sleep characteristics. These results suggest that coffee and caffeine may be used in normal subjects to induce symptoms mimicking those of insomnia. Such a tool should promote further understanding of insomnia.
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PMID:Dose-related sleep disturbances induced by coffee and caffeine. 18 23

In this study, the participation of the adenylcyclase--cAMP system of the rat septal area in the mediation of the natriuretic, kaliuretic and diuretic effects of noradrenaline (NA) was investigated. The intraseptal injection of 20 nmol of NA caused a significant increase in the urinary excretion of Na+ and K+ as well as in the urinary volume during the 2 hr period following the intracerebral injection which was blocked by 40 nmol of phentolamine, locally injected, 30 min before the catecholamine. In contrast, pretreatment with propranolol (100 nmol) potentiated the effects of NA on salt and water renal excretion. The intraseptal injection of 3.12 to 50 nmol of dibutryrl cyclic adenosine monophosphate (db cAMP) caused dose-dependent increase in natriuresis and kaliuresis, but a decrease in urinary volume. Under the same experimental conditions, caffeine administration (6.25 to 100 nmol) also induced dose-dependent increases in Na+ and K+ urinary output. These results indicate that the saluretic effect of NA may be mediated by an alpha receptor-induced activation of the adenylcyclase--cAMP system in the septal area.
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PMID:Role played by the adenylcyclase-cAMP system of the rat septal area on Na+, K+ and water renal excretion. 19 10

The current state of knowledge in regard to nutritional requirements for pregnant and lactating women and for women who are taking oral contraceptives is reviewed. During pregnancy caloric intake should be moderately increased, and the consumption of 30-60 mg of iron and 800-1200 mg of calcium is recommended. Phosphorus intake should also be increased, but this increase should be balanced by a corresponding increase in calcium intake. Consumption of vitamins A and D should be increased but excessive increases should be avoided. Vitamin E should be slightly increased. The desirability of increasing vitamin K is till a matter of dispute. Pregnant women have a slightly increased need for most water soluble vitamins. Research has adequately demonstrated the need to increase folic acid and B6 consumption. There is some evidence that iodine, chromium, and zinc deficiencies may be teratogenic. Some care should be taken not to overconsume sodium, but the need for stringest restriction is unwarranted. Heavy consumption of alcohol and caffeine should definitely be discouraged during pregnancy. Certain problems experienced by pregnant women, such as nausea, may be managed through nutritional modification. The increased nutritional needs for lactating women can, in most cases, be met by increasing milk consumption by 3-3 1/2 cup/day and by consuming a well balanced diet. The content of maternal milk may to some extent be altered by the consumption patterns of the mothers. Ingestion of certain drugs and chemicals may also alter maternal milk. The use of oral contraceptives apparently affects metabolism, but the consequences of these effects are largely unknown. Oral contraceptive usage generally increases the serum levels of triglycerides, iron, copper, and vitamin A and reduces levels of some B vitamins of vitamin C and of zinc and albumin. These effects vary from woman to woman and at the present time there is no agreement on the need for dietary supplementation. The effects of a variety of drugs on lactating women and the effects of oral contraceptive usage on nutritional status are presented in tabular form.
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PMID:Nutrition during pregnancy, lactation, and oral contraception. 25 28

Coffee prepared in the usual way for drinking contains a substance(s) that is mutagenic to Salmonella typhimurium TA100 without mammalian microsomal enzymes. One cup of coffee (200 ml) contains mutagen(s) inducing 1.4-4.6 X 10(5) revertants under standard conditions. Instant coffee too is mutagenic to TA100 and one cup of instant coffee prepared from 1 g of coffee powder and 200 ml of water induced 5.6-5.8 X 10(4) revertants of TA100. Caffeine-free instant coffee also has similar mutagenicity. Addition of microsomal enzymes abolished the mutagenicity. Black tea, green tea and Japanese roasted tea were also mutagenic to TA100 without S9 mix and one cup of these teas prepared in the ordinary way produced 1.7-3.8 X 10(4) revertants of TA100. Black tea and green tea were also mutagenic to TA98 in the presence of S9 mix after treatment with a glycosidase from Aspergillus niger, hesperidinase. This type of mutagen in one cup of black tea induced 2.4 X 10(5) revertants of TA98.
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PMID:Mutagens in coffee and tea. 39 Mar 84

The effects of caffeine (3.125, 6.25, 12.5, 25.0, 50.0, and 100.0 mg/kg) on lever pressing, schedule induced licking, and water consumption induced by a fixed time 1 min schedule of food reinforcement were studied. Changes in these dependent variables were assessed when animals were reduced to 80% of their initial body weight by partial food deprivation and when body weight recovered after the animals were returned to conditions of ad lib feeding. Results indicate similar decreases in licking and drinking at the highest doses of caffeine under both feeding and body weight conditions. The results were compared to previous research which evaluated the effects of caffeine on adjunctive behavior.
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PMID:Effects of caffeine on FT-1 min schedule induced drinking at different body weights. 50 15

The distribution coefficient of caffeine (water/n-Octanol) and the estimation of caffeine in urine after local application indicate to a high permeation rate of caffeine through the skin. This could be confirmed by using different vehicles in vivo and in vitro. 14C labeled caffeine penetrates rapidly the epidermis and corium. The maximum of absorption is reached at 100 min after local application in vivo. In vitro by absence of the transport possibilities of blood and lymph vessels, the concentration at 1,000 min after local application is 450 X higher than in vivo. Therefore, after 1,000 min in vivo the concentration of caffeine in the different skin layers is very low.
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PMID:The quantitative distribution of percutaneously applied caffeine in the human skin. 52 50

Exposure of male Wistar rats to 12.3 mumol/l (300 ppm) isopropanol vapour for 5-21 weeks, 5 days a week for 6 h daily with a simultaneous ethanol administration in drinking water (5% v/v) caused a significant increase in isopropanol removal as assessed by blood isopropanol and acetone determinations. Ethanol treatment caused a marked synergistic effect during early exposure. Neurochemical studies revealed decreased superoxide dismutase and azoreductase activities at the end of the exposure whereas increased protein degradation was found in glial cells isolated from ethanol-fed rats throughout the experiment. Analyses of spinal cord axon lipid composition showed increases in cholesterol content in relation to lipid phosphorus in animals exposed to isopropanol or to the isopropanol and ethanol combination. Behavioural tests indicated minor effects on emotional reactivity from the 10th week onwards with isopropanol exposure whereas caffeine-stimulated activity was augmented only in rats ingesting ethanol. Co-exposure to isopropanol vapour abolished the increased excitability. The data indicate that marked metabolic and functional adaptation towards the small-molecular-weight alcohols takes place at moderate dose levels.
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PMID:Neurochemical and behavioural effects of extended exposure to isopropanol vapour with simultaneous ethanol intake. 54 42


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