BIOLOGICAL HALF-LIFE OF CAFFEINE IN PIGS

1970 ◽  
Vol 50 (1) ◽  
pp. 49-54 ◽  
Author(s):  
H. M. CUNNINGHAM
Keyword(s):  
Oral Dose ◽  
Water Content ◽  
Single Oral Dose ◽  
Plasma Levels ◽  
Half Life ◽  
Intramuscular Injection ◽  
Peak Plasma ◽  
Growing Pigs ◽  
Sufficient Time ◽  
Biological Half Life

Five experiments were conducted with growing pigs to determine the biological half-life of caffeine after injection or various periods of ingestion. Peak plasma caffeine levels were reached within 5 hr after a single oral dose and 2 hr after intramuscular injection, and then declined with a biological half-life of about 12 hr. The caffeine content of tissues was approximately proportional to their water content and 6% of orally administered caffeine was excreted in the urine. Upon continuous ingestion of caffeine, peak plasma levels were reached within 2 days, indicating that accumulation was quite limited. When 1.5 g of caffeine per kg of feed was fed from weaning to market weight, the withdrawal of caffeine 2 days prior to slaughter was sufficient time to insure that caffeine levels in the liver, muscle, kidney and backfat were below 1 μg/g.

scholarly journals Pharmacokinetics of Tinidazole in Chinese subjects: Comparison of Mongolian, Korean, Hui, Uighur and Han nationalities

2009 ◽  
Vol 12 (2) ◽  
pp. 175 ◽  
Author(s):  
Xin-Yu Chang ◽  
Tao Guo ◽  
Dong-Ya Xia
Keyword(s):  
Oral Dose ◽  
Single Oral Dose ◽  
Half Life ◽  
Peak Plasma ◽  
Peak Plasma Concentration ◽  
Elimination Rate ◽  
Area Under The Curve ◽  
Elimination Half ◽  
Pharmacokinetic Properties ◽  
Chinese Subjects

ABSTRACT - Purpose. This study investigated the pharmacokinetics of tinidazole in subjects of five different Chinese nationalities (Han, Mongolian, Korean, Hui, and Uighur). Methods. Fifty healthy subjects (five male and five female of each nationality) were recruited for the study, and each received 1 g tinidazole. A total of 14 blood samples were collected over a 72-hour period after administration. Results. Pharmacokinetic profiles, including area under the curve from time zero to infinity (AUC0-inf), peak plasma concentration (Cmax), time to reach Cmax (tmax), oral clearance (CL/F), elimination rate constant (Ke), and elimination half-life (t1/2), were determined following a single oral dose of tinidazole. The respective pharmacokinetic properties of Han, Mongolian, Korean, Hui, and Uighur nationalities were: half-life (h): 16.94±2.40, 16.40±1.79, 16.63±1.82, 16.81±1.56, 14.34±1.92; Cmax (μg/mL): 19.04±2.42, 19.22±4.93, 20.83±3.33, 20.25±4.05, 18.81±3.10; AUC0-inf (h•μg/mL): 483.13±65.65, 479.70±99.74, 511.07±53.47, 514.25±130.78, 388.58±37.37. The t1/2 and AUC0-inf of Uighur subjects were significantly lower (p =0.023, 0.011) and the CL/F and Ke were significantly higher (p = 0.003, 0.013) than those of other nationalities. After normalization by weight, the differences in AUC0-inf and CL/F between Uigur subjects and those of other races were still significant. Conclusions. The results indicate that ethnicity had significant impact on the pharmacokinetics of tinidazole after a single oral dose in healthy volunteers of different nationalities in China.

scholarly journals Interspecies Comparison of Pharmacokinetics of the Novel Triazole Antifungal Agent SYN-2869 and Its Derivatives

2000 ◽  
Vol 44 (4) ◽  
pp. 910-915 ◽  
Author(s):  
Jehangir K. Khan ◽  
Hashem Montaseri ◽  
Marzena Poglod ◽  
Hai-Zhi Bu ◽  
Zhong Zuo ◽  
...  
Keyword(s):  
Oral Dose ◽  
Single Oral Dose ◽  
Half Life ◽  
Animal Species ◽  
Intravenous Dose ◽  
Single Intravenous Dose ◽  
Sprague Dawley ◽  
Time Curve ◽  
Toxicological Evaluation ◽  
Significant Difference

ABSTRACT The pharmacokinetics and distribution in tissue of several novel triazole antifungal agents were studied in different animal species in order to select an appropriate lead compound. The purpose of the study was also to determine species differences in pharmacokinetics for SYN azoles to select the most appropriate species for secondary efficacy and toxicological evaluation of the selected compound. SYN-2836, SYN-2869, SYN-2903, and SYN-2921 were rapidly absorbed into the systemic circulation and reached maximum concentrations (C maxs) of 7.31 ± 2.53, 6.29 ± 0.85, 6.16 ± 0.39, and 3.41 ± 0.34 μg/ml, respectively, in BALB/c mice after administration of an oral dose of 50 mg/kg of body weight, with bioavailability being greater than 45% in all mice. The areas under the concentration-time curve from time zero to infinity (AUC0–∞s) after administration of a single intravenous dose of 20 mg/kg to mice varied between 25.0 and 63.6 μg · h/ml. The half-life was in the range of 4.5 to 6 h. In Sprague-Dawley rats there was no significant difference in AUC0–∞ after administration of a single intravenous dose of 20 mg/kg, but on oral administration, the bioavailability of SYN-2836 was extremely low, while that of SYN-2869 was only 14.7%. In New Zealand White rabbits the C max and the time to reach C max for SYN-2836 and SYN-2869 after administration of a single oral dose of 50 mg/kg were similar. There were significant differences in AUC0–∞ and half-life between SYN-2836 and SYN-2869. On the other hand, in beagle dogs theC max and AUC0–∞ of SYN-2836 after administration of a single oral dose of 30 mg/kg were 4.82 ± 1.54 μg/ml and 41.8 ± 15.7 μg · h/ml, respectively, which were threefold higher than those of SYN-2869. The concentrations of the SYN compounds in tissue indicated that the AUC0–∞s of SYN-2836, SYN-2869, SYN-2903, and SYN-2921 in mouse lungs were significantly different from each other. The ratios of the concentrations of the SYN azoles in lungs to those in plasma were also significantly different from those for itraconazole. Among the SYN azoles the highest concentration in the lungs was found for SYN-2869. The higher level of distribution of SYN-2869 into lung tissue was considered to contribute to the potent efficacy in respiratory tract infection models compared with the potency of itraconazole. Significant differences in the pharmacokinetics of these compounds were observed in different animal species, and selection of an animal model for further evaluation was based on results obtained from these studies.

Inhibitory effect of cyproheptadine on ACTH secretion in patients with Addison's disease

1983 ◽  
Vol 102 (1) ◽  
pp. 111-115
Author(s):  
P. Loli ◽  
F. Frascatani ◽  
D. Gelli ◽  
M. Maggioni ◽  
F. Muratori ◽  
...  
Keyword(s):  
Oral Dose ◽  
Single Oral Dose ◽  
Drug Administration ◽  
Plasma Levels ◽  
Addison’S Disease ◽  
Inhibitory Effect ◽  
Feedback Mechanism ◽  
Addison's Disease ◽  
Acth Secretion ◽  
Acth Release

Abstract. In 14 patients with Addison's disease plasma levels of ACTH were studied after administration of a single oral dose (16 mg) of cyproheptadine. The drug administration was followed by an inhibition of ACTH release. These results support the view that cyproheptadine may exert an inhibitory effect on ACTH secretion in subjects whose corticosteroid feedback mechanism is normal. We hypothesize that the effect of cyproheptadine might be related to its anti-serotonin or anti-histaminergic action.

Absorption, Tissue Distribution and Elimination of 4-[3H]-Epigallocatechin Gallate in Beagle Dogs

2003 ◽  
Vol 22 (3) ◽  
pp. 187-193 ◽  
Author(s):  
Robert R. Swezey ◽  
Daphne E. Aldridge ◽  
Susanna E. Le Valley ◽  
James A. Crowell ◽  
Yukihiko Hara ◽  
...  
Keyword(s):  
Oral Administration ◽  
Tissue Distribution ◽  
Plasma Levels ◽  
Half Life ◽  
Peak Plasma ◽  
Parent Compound ◽  
Epigallocatechin Gallate ◽  
Total Radioactivity ◽  
Repeat Dose ◽  
Beagle Dogs

Polyphenols found in tea are potent antioxidants and have inhibitory activity against tumorigenicity. The purpose of the described study was to assess the absorption, tissue distribution, and elimination of epigallocatechin gallate (EGCG), the principal catechin found in green tea, in a nonrodent species. 4-[3H]-EGCG was administered to beagle dogs by intravenous (IV) and oral routes. Following IV administration of 25 mg/kg, radioactivity in the bloodstream resided predominantly in the plasma. Distribution occurred during the first hour, and the plasma levels of total radioactivity declined with a mean half-life of approximately 7 hours. The apparent volume of distribution (0.65 l/kg) indicated wide distribution, and the total body clearance (1.01 ml/min-kg) was low. A subsequent single oral dose (250 mg/kg) was rapidly absorbed, with peak plasma levels at about 1 hour after administration, followed by elimination with a mean half-life of 8.61 hours. The mean area under the curve (AUC) for total radioactivity was approximately 20% of the value following IV administration (corrected for dose administered). Excretion of radioactivity in the feces predominated over urinary excretion following both IV and oral administration of [3H]-EGCG. Tissue distribution was determined 1 hour after an IV dose (25 mg/kg) administered after 27 days of oral treatment with EGCG (250 mg/kg/day) to mimic chronic consumption of tea. Radioactivity was distributed to a variety of epithelial tissues; the highest concentrations were observed in the liver and gastrointestinal tract tissues. Repeat dose oral administration of EGCG resulted in significantly lower blood radioactivity compared to the concentration following a single dose. These results are generally in accord with previous studies in rodents and indicate that, after oral administration, EGCG (as parent compound and metabolites) is widely distributed to tissues where it can exert a chemopreventive effect.

scholarly journals Interaction between Grapefruit Juice and Praziquantel in Humans

2002 ◽  
Vol 46 (5) ◽  
pp. 1614-1616 ◽  
Author(s):  
Nelly Castro ◽  
Helgi Jung ◽  
Roberto Medina ◽  
Dinora González-Esquivel ◽  
Mario Lopez ◽  
...  
Keyword(s):  
Water Treatment ◽  
Oral Dose ◽  
Single Oral Dose ◽  
Half Life ◽  
Maximum Concentration ◽  
Grapefruit Juice ◽  
Time Curve ◽  
Elimination Half Life ◽  
Concentration Time ◽  
Elimination Half

ABSTRACT After a single oral dose of praziquantel with 250 ml of grapefruit juice, the area under the concentration-time curve and the maximum concentration in plasma of praziquantel (C max) were significantly increased (C max for water treatment, 637.71 ± 128.5 ng/ml; and C max for grapefruit juice treatment, 1,037.65 ± 305.7 ng/ml, P < 0.05). No statistically significant differences were found in the time to maximum concentration of drug in plasma or elimination half-life.

scholarly journals Plasma appearance and disappearance of an oral dose of 25-hydroxyvitamin D2in healthy adults

2011 ◽  
Vol 107 (8) ◽  
pp. 1128-1137 ◽  
Author(s):  
Kerry S. Jones ◽  
Inez Schoenmakers ◽  
Les J. C. Bluck ◽  
Shujing Ding ◽  
Ann Prentice
Keyword(s):  
Vitamin D ◽  
Plasma Concentration ◽  
Oral Dose ◽  
Half Life ◽  
Peak Plasma ◽  
Peak Plasma Concentration ◽  
Post Dose ◽  
Vitamin D Metabolism ◽  
Blood Samples ◽  
Potential Biomarker

25-Hydroxyvitamin D (25(OH)D) half-life is a potential biomarker for investigating vitamin D metabolism and requirements. We performed a pilot study to assess the approach and practical feasibility of measuring 25(OH)D half-life after an oral dose. A total of twelve healthy Gambian men aged 18–23 years were divided into two groups to investigate the rate and timing of (1) absorption and (2) plasma disappearance after an 80 nmol oral dose of 25(OH)D2. Fasting blood samples were collected at baseline and, in the first group, every 2 h post-dose for 12 h, at 24 h, 48 h and on day 15. In the second group, fasting blood samples were collected on days 3, 4, 5, 6, 9, 12, 15, 18 and 21. Urine was collected for 2 h after the first morning void at baseline and on day 15. 25(OH)D2plasma concentration was measured by ultra-performance liquid chromatography-tandem MS/MS and corrected for baseline. Biomarkers of vitamin D, Ca and P metabolism were measured at baseline and on day 15. The peak plasma concentration of 25(OH)D2was 9·6 (sd0·9) nmol/l at 4·4 (sd1·8) h. The terminal slope of 25(OH)D2disappearance was identified to commence from day 6. The terminal half-life of plasma 25(OH)D2was 13·4 (sd2·7) d. There were no significant differences in plasma 25(OH)D3, total 1,25(OH)2D, parathyroid hormone, P, Ca and ionised Ca and urinary Ca and P between baseline and day 15 and between the two groups. The present study provides data on the plasma response to oral 25(OH)D2that will underpin and contribute to the further development of studies to investigate 25(OH)D half-life.

PLASMA LEVELS OF NORETHINDRONE AFTER SINGLE ORAL DOSE ADMINISTRATION OF NORETHINDRONE AND LYNESTRENOL

1979 ◽  
Vol 10 (1) ◽  
pp. 29-38 ◽  
Author(s):  
V. ODLIND ◽  
E. WEINER ◽  
A. VICTOR ◽  
E. D. B. JOHANSSON
Keyword(s):  
Oral Dose ◽  
Single Oral Dose ◽  
Plasma Levels ◽  
Dose Administration

scholarly journals Plasma levels after a single oral dose of 1.5 g ornidazole.

1977 ◽  
Vol 53 (4) ◽  
pp. 236-239
Author(s):  
I Matheson ◽  
K H Johannessen ◽  
B Bjorkvoll
Keyword(s):  
Oral Dose ◽  
Single Oral Dose ◽  
Plasma Levels

scholarly journals Significant Increase in Salivary Substance P Level after a Single Oral Dose of Cevimeline in Humans

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Yosuke Suzuki ◽  
Hiroki Itoh ◽  
Kohei Amada ◽  
Ryota Yamamura ◽  
Yuhki Sato ◽  
...  
Keyword(s):  
Substance P ◽  
Oral Dose ◽  
Single Oral Dose ◽  
Plasma Levels ◽  
Therapeutic Agent ◽  
Venous Blood ◽  
Muscarinic Acetylcholine Receptor ◽  
Salivary Secretion ◽  
Calcitonin Gene ◽  
Highly Sensitive

Cevimeline is a novel muscarinic acetylcholine receptor agonist currently being developed as a therapeutic agent for xerostomia. We examined the effects of cevimeline on salivary and plasma levels of substance-P- (SP-), calcitonin-gene-related-peptide- (CGRP-), and vasoactive-intestinal-polypeptide- (VIP-) like immunoreactive substances (ISs) in humans. An open-labeled crossover study was conducted on seven healthy volunteers. Saliva volume was measured, and saliva and venous blood samples were collected before and 30–240 min after a single oral dose of cevimeline or placebo. Salivary and plasma levels of SP-, CGRP-, and VIP-IS were measured using a highly sensitive enzyme immunoassay. A single oral dose of cevimeline resulted in significant increases in salivary but not plasma SP-IS level compared to placebo. Cevimeline administration did not alter the salivary or plasma levels of CGRP-IS or VIP-IS compared to placebo. Significant increases in salivary volume were observed after cevimeline administration compared to placebo. A significant correlation was observed between the total release of SP-IS and that of salivary volume. These findings suggest an association of SP with the enhancement of salivary secretion by cevimeline.

Stoffwechselverhalten des anorganischen Kobalts und des in der Vitamin B12- bzw. Vitamin B12-Coenzym-Struktur organisch gebundenen Kobalts im Säugetier-Organismus

1964 ◽  
Vol 19 (11) ◽  
pp. 1032-1042 ◽  
Author(s):  
H. C. Heinrich ◽  
E. E. Gabbe
Keyword(s):  
Vitamin B12 ◽  
Half Life ◽  
Human Liver ◽  
Intramuscular Injection ◽  
Turnover Rate ◽  
Cobalt Content ◽  
Whole Body ◽  
Vitamin B ◽  
Biological Half Life ◽  
Body Retention

Chromatographically pure, vitamin B12-free 60CoCl2 as well as 60Co-vitamin B12 (60Co-cyanocobalamin and 60Co-aquocobalamin) and 60Co-vitamin B12-coenzyme (60Co-5.6-dimethylbenzimidazol-C5′-deoxyadenosyl-cobamid) were given orally and by injection in smallest amounts (10 — 100 pMol = 0.59-5.9 ng Co2®, 100 pMol = 136 ng vitamin B12 and 100 pMol = 158 ng vitamin B12-coenzyme) to female Sprague-Dawley rats.The whole body retention and excretion of the 60Co label was measured in a large volume radioactivity detector with liquid organic scintillators and 4 π-geometry. The biological half life and whole body metabolic turnover rate were calculated for the inorganic and organic cobalt from the kinetics of the 60Co whole body retention.After oral application of 100 pMol 60Co2® nearly all the 60Co is excreted already after 2 days within the faeces (90%), and the urine (15%). Only about 0.9% of the 60Co2⊕ leaves the rats with a biological half life of 18 days. After intramuscular injection of 100 pMol 60Co2⊕ about 91% of the 60Co are excreted in the urine and 10% in the faeces within four weeks. Only 4.6% of the 60Co2⊕ were eliminated with a biological half life of 28 days. The intramuscular injection of only 10 pMol 60Co2⊕ resulted in a faecal excretion of 82%, and an urinary excretion of 21% of the 60Co. A biological half life of 23 days was calculated for 8.6% of the 60Co2⊕. Inorganic cobalt is therefore practically not retained in the body and rapidly excreted mainly with the urine after injection and mainly within the faeces after oral uptake.In contrast to the inorganic cobalt a completely different metabolic behaviour is typical for the cobalt, which is incorporated in the organic structure of the vitamin B12- and vitamin B12-coenzyme molecules. This organic cobalt accumulates in the storage organs and tissues (kidney, liver etc.) after absorption as well as after injection of 100 pMol 60Co-vitamin B12 and 60Co-vitamin B12coenzyme. Only 15% of the 60Co-cyanocobalamin and 9—10% of the 60Co-aquocobalamin and 60°Covitamin B12-coenzyme are excreted within 48 hours after injection. The organ and tissue incorporated 60Co-vitamin B12 and 60Co-vitamin B12-coenzyme is metabolized with a biological half life of about 52 days. From the whole body pool size of 20 μg vitamin B12 and the biological half life a metabolic turnover rate of 0.27 μg vitamin B12/day or 1.34% of the vitamin-B12-pool per days was calculated for the whole body of the rat.The lacking organ and tissue retention of absorbed and injected 60Co2⊕ and its short biological half life in rats (if compared with the organic cobalt in the vitamin B12-structure) as well as the comparison of the total cobalt content of human liver (measured by physical techniques) with the cobalt content calculated from the vitamin B12-content of human liver (measured by microbiological assay) do not support a biological significance and function of inorganic cobalt in mammals. There is no evidence at the moment that any cobalt besides the cobalt in the vitamin B12 and vitamin B12-coenzymes is existing and biochemically active in humans or animals.

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