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1.
Domest Anim Endocrinol ; 74: 106515, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711284

RESUMO

Estradiol-17ß (E2) and progesterone (P4) regulate oviductal functions, providing a suitable environment for the transport and maturation of gametes, fertilization, and embryonic development. In addition to the E2 and P4 nuclear receptors, estrogen receptor (ESR) α and ß, nuclear progesterone receptor (PGR), nongenomic mechanisms through G protein-coupled estrogen receptor (GPER1), and progesterone receptor membrane component (PGRMC) 1 and 2 mediate E2 and P4 actions. This study aimed to characterize the local endocrine environment of the oviduct by examining the oviductal E2 and P4 concentrations and their receptors' mRNA expression during the periovulatory phase. The bovine oviducts were collected in a slaughterhouse and the days postovulation were estimated according to state of the ovaries and the uterus. Samples of the ampulla and isthmus ipsilateral and contralateral to the preovulatory follicle or corpus luteum were collected on Days 19 to 21, Days 0 to 1, Days 2 to 4, and Days 5 to 7 of the estrous cycle. The effects of the estrous cycle phase and oviductal region (ampulla and isthmus) and side (ipsilateral and contralateral) were analyzed by 3-way ANOVA. Moreover, to clarify the regulatory mechanisms of the mRNA expression of hormone receptors, the effects of E2 and P4 on mRNA expression in the oviduct were examined by multiple linear regression. The oviductal endocrine milieu on Days 19 to 21 was characterized by an E2-dominant environment with high E2 and low P4, high ESR1 and PGR mRNA expression, and low ESR2, GPER1, and PGRMC2 mRNA expression, whereas the corresponding on Days 0 to 1 was characterized by the endocrine milieu without hormone dominance. The environment on Days 2 to 4 and Day 5 to 7 was characterized by opposite tendency of oviductal hormone concentrations and their receptors' mRNA expression to Days 19 to 21. Additionally, the ipsilateral oviduct had the more P4-dominant endocrine milieu, with lower E2 and higher P4 concentrations, and different expression of ESR1/2, GPER1, PGR, and PGRMC2 mRNA when compared with the contralateral oviduct on Days 2 to 4 and Days 5 to 7, except for PGRMC1. Although oviductal E2 and P4 influenced the mRNA expression of ESR1/2, GPER1, PGR, and PGRMC1/2, their effects were different between regions and sides. In summary, the oviductal endocrine milieu varies according to the estrous cycle phase and the oviductal region and side, which may be involved in the estrous cycle phase-specific and oviductal region-specific and side-specific functions.


Assuntos
Bovinos/fisiologia , Corpo Lúteo/fisiologia , Tubas Uterinas/química , Hormônios Esteroides Gonadais/análise , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Animais , Estradiol/análise , Receptor alfa de Estrogênio/genética , Ciclo Estral/fisiologia , Feminino , Fertilização/fisiologia , Progesterona/análise , RNA Mensageiro/análise , Receptores de Progesterona/genética
2.
Pharmazie ; 73(12): 740-743, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30522561

RESUMO

A history of hypertension is a known risk factor for delirium in patients in intensive care units, but the effect of antihypertensive agents on delirium development is unclear. Nicardipine, a calcium channel blocker, is widely used in ICU as a treatment agent for hypertensive emergency. This study investigated the relationship between the administration of nicardipine hydrochloride and delirium development in patients under mechanical ventilation. We conducted a medical chart review of 103 patients, who were divided into two groups according to the use of nicardipine hydrochloride. The prevalence of delirium was compared with respect to factors such as age, sex, laboratory data, and medical history, by multivariate analysis. 21 patients (20.4 %) were treated with nicardipine hydrochloride in 103 patients. The treatment and non-treatment groups differed significantly in age (72 vs. 65 years) and history of high blood pressure (57% vs. 11%). Multivariate analysis revealed that patients in the treatment group developed delirium significantly less often than those in the non-treatment group (19% vs. 48%). These results suggested that treatment of high blood pressure with nicardipine hydrochloride is a possible method for preventing the development of delirium.


Assuntos
Delírio/epidemiologia , Hipertensão/tratamento farmacológico , Nicardipino/administração & dosagem , Respiração Artificial , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacologia , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/farmacologia , Delírio/etiologia , Delírio/prevenção & controle , Feminino , Humanos , Hipertensão/complicações , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Nicardipino/farmacologia , Prevalência , Estudos Retrospectivos , Fatores de Risco
3.
Environ Pollut ; 243(Pt B): 1008-1014, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30248600

RESUMO

In the 21st century, severe droughts associated with climate change will increase biomass burning (BB) in Brazil caused by the human activities. Recent droughts, especially in 2005, 2010, and 2015, caused strong socioeconomic and environmental impacts. The 2015 drought considered the most severe since 1901, surpassed the 2005 and 2010 events in respect to area and duration. Herein, based on satellite data, the 2005, 2010 and 2015 drought impacts on wildfire episodes and carbon monoxide (CO) variability during the dry and the dry-to-wet transition seasons were examined. The BB occurrences in the dry season were fewer during 2015 than during 2005 (-44%) and 2010 (-47%). Contrasting, the BB events in the dry-to-wet transition season, were higher during 2015 than during 2005 (+192%) and 2010 (+332%). The BB outbreaks were concentrated in the southern and southwestern Amazon during 2005, in the Cerrado region during 2010, and mainly in the central and northern Amazon during 2015, an area normally with few fires. The CO concentration showed positive variations (up to +30%) occurred in the southern Amazon and central Brazil during the 2005 and 2010 dry seasons, and north of 20 °S during the 2015-2016 dry-to-wet transition season. The BB outbreaks and the CO emissions showed a considerable spatiotemporal variability among the droughts of 2005, 2010, and 2016, first of them driven by local conditions in the tropical North Atlantic (TNA), characterized by warm than normal sea surface waters and the other two by the El Niño occurrences.


Assuntos
Monóxido de Carbono/análise , Secas/estatística & dados numéricos , Monitoramento Ambiental , Incêndios/estatística & dados numéricos , Biomassa , Brasil , Mudança Climática , Atividades Humanas , Estações do Ano
4.
Prev Vet Med ; 127: 50-5, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27094140

RESUMO

This was a retrospective cohort study using data from the insurance scheme provided by the Japanese Mutual Aid Association (NOSAI). The population of interest comprised all cattle born on NOSAI-client farms in the Japanese prefecture of Hokkaido, Japan for the period 1 April 2005-31 March 2009. The outcome of interest was whether or not at least one calf was stillborn, had died during delivery or died during the first 24 hours of life for a given calving event, termed first 24h mortality risk. A mixed-effects logistic regression model was developed to identify explanatory variables associated with first 24h mortality risk. The final data set comprised details of 1,281,737 calving events on a total of 5172 dairy herds from 19 NOSAI branches located throughout the prefecture of Hokkaido. Throughout the study period 7.68 (95% CI 7.64-7.73) of every 100 calving events had at least one calf that was either stillborn, dead at the time of delivery or dead during the first 24h of life. Factors that were positively associated with an increase in first 24h mortality risk included delivery during the colder months of the year (November-March), being of Wagyu breed, having a multipara dam, multiple (as opposed to single) birth deliveries, and delivery in larger herds. ​After adjusting for the fixed effects included in our multilevel model, 89% of the unexplained variation in first 24h mortality risk was at the calving event level. We propose that the data recording requirements of the NOSAI scheme are extended to include details of calving events (e.g. the presence or absence of dystocia) and details of the way in which calves are managed post delivery. This would allow more subtle risk factors for calf mortality to be identified which, in turn, will lead to refinement of recommendations for calf management during the first 24h of life in this area of Japan.


Assuntos
Doenças dos Bovinos/epidemiologia , Natimorto/veterinária , Animais , Animais Recém-Nascidos , Bovinos , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/mortalidade , Estudos de Coortes , Indústria de Laticínios , Japão/epidemiologia , Modelos Logísticos , Estudos Retrospectivos , Fatores de Risco , Natimorto/epidemiologia
5.
J Dairy Sci ; 98(12): 8764-74, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26454289

RESUMO

The aim of this study was to identify the metabolic changes that have occurred in Holstein-Friesian cows in Japan over the past 2 decades, based on long-term metabolic profiles. From 1987 to 2004, metabolic profile tests were conducted in 1,700 dairy herds containing ~50,000 cows. The cows were divided into 5 lactation stage groups: early (calving to 49 d in milk, DIM), peak (50-109 DIM), mid (110-209 DIM), and late (210 to dry-off) lactation and the dry period. Principal component analysis was applied to the metabolic profiles at each lactation stage separately to investigate changes in metabolic profiles across the multiyear periods 1987-1992, 1993-1998, and 1999-2004. We determined that cows have probably experienced increasing negative energy balance, energy deficiency, and liver dysfunction during the past 2 decades in Japan.


Assuntos
Bovinos/metabolismo , Metaboloma , Animais , Metabolismo Energético/fisiologia , Feminino , Japão , Lactação/fisiologia , Fígado/fisiologia , Leite , Análise de Componente Principal
6.
Rev Sci Instrum ; 86(5): 056103, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26026564

RESUMO

A CR-39 plastic nuclear track detector was used for quality assurance of mixed oxide fuel pellets for next-generation nuclear power plants. Plutonium (Pu) spot sizes and concentrations in the pellets are significant parameters for safe use in the plants. We developed an automatic Pu detection system based on dense α-radiation tracks in the CR-39 detectors. This system would greatly improve image processing time and measurement accuracy, and will be a powerful tool for rapid pellet quality assurance screening.

7.
J Dairy Sci ; 98(1): 318-21, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25465564

RESUMO

In this study, we examined the effect of the locations of the first-wave dominant follicle (DF) and corpus luteum (CL) on fertility. In total, 350 artificial insemination (AI) procedures were conducted (lactating dairy cows: n=238, dairy heifers: n=112). Ovulation was confirmed 24 h after AI. The locations of the first-wave DF and CL were examined 5 to 9d after AI using rectal palpation or transrectal ultrasonography. Lactating dairy cows and dairy heifers were divided into 2 groups: (1) the ipsilateral group (IG), in which the DF was ipsilateral to the CL; and (2) the contralateral group (CG), in which the DF was contralateral to the CL. Pregnancy was diagnosed using transrectal ultrasonography 40d after AI. Conception rates were 54.0% in all cattle: 48.9% in lactating dairy cows, and 58.9% in dairy heifers. The incidence of the first-wave DF location did not differ between IG and CG (all cattle: 184 vs. 166; lactating cows: 129 vs. 109; heifers: 55 vs. 57 for IG vs. CG). Conception rates were lower in IG than in CG (all cattle: 40.2 vs. 69.3%; lactating dairy cows: 38.0 vs. 67.0%; dairy heifers: 45.5 vs. 73.7%, for IG vs. CG). Conception rate was not affected by season or live weight in heifers and lactating cows. In addition, days in milk at AI, milk production, body condition score, and parity did not affect conception in lactating cows. In summary, development of the first-wave DF in the ovary ipsilateral to the CL was associated with reduced conception rates in both lactating cows and heifers.


Assuntos
Bovinos/fisiologia , Corpo Lúteo/fisiologia , Fertilidade , Leite/metabolismo , Folículo Ovariano/fisiologia , Animais , Feminino , Fertilização/fisiologia , Inseminação Artificial/veterinária , Lactação/fisiologia , Ovário/fisiologia , Ovulação/fisiologia , Paridade , Gravidez
8.
J Chromatogr B Biomed Sci Appl ; 688(1): 101-6, 1997 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-9029319

RESUMO

A sensitive reversed-phase high-performance liquid chromatographic (HPLC) method with fluorescence detection was developed for the analysis of a new angiotensin II receptor antagonist, E4177, in human plasma and urine. The analyte and internal standard (I.S.) are extracted from acidified plasma and urine by liquid-liquid extraction and then refined by solid-phase extraction. The extraction recovery was greater than 90%. E4177 and I.S. were separated from endogenous components in plasma and urine on a C18 column using a mobile phase of acetonitrile-water-85% phosphoric acid (27.3:72.0:0.7, v/v). The eluent was monitored by fluorescence with excitation and emission set at 280 and 380 nm, respectively. The assay was linear from 2.5 to 1000 ng/ml of plasma and from 5 to 1500 ng/ml of urine. The limit of quantification was 2.5 and 5 ng/ml for plasma and urine, respectively. Inter- and intra-day coefficients of variation for the plasma and urine ranged from 0.6 to 4.7%. E4177 was stable in plasma and urine for at least 9 months during storage at -20 degrees C, respectively. The method was successfully applied to the determination of E4177 in plasma and urine for a pharmacokinetic study.


Assuntos
Antagonistas de Receptores de Angiotensina , Cromatografia Líquida de Alta Pressão/métodos , Imidazóis/análise , Piridinas/análise , Administração Oral , Ritmo Circadiano , Estabilidade de Medicamentos , Congelamento , Humanos , Imidazóis/administração & dosagem , Imidazóis/química , Imidazóis/farmacocinética , Modelos Lineares , Piridinas/administração & dosagem , Piridinas/química , Piridinas/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência , Fatores de Tempo
9.
J Chromatogr B Biomed Appl ; 660(1): 211-20, 1994 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-7858718

RESUMO

A method for the simultaneous determination of E3810, 2-[(4-(3-methoxypropoxy)-3-methyl pyridine-2-yl)methyl sulfinyl]-1H-benzimidazole sodium salt and its four metabolites, demethylated-E3810 (DM), demethylated thioether-E3810 (DMTE), sulfone-E3810 (S), and thioether-E3810 (TE), in human plasma by high-performance liquid chromatography (HPLC) with UV absorbance detection has been established. The correlation coefficient for all the standard curves was 0.998 or greater. The quantitation limit was 5 ng/ml for E3810 and 20 ng/ml for each of its four metabolites. The recovery of E3810 and its four metabolites from human plasma was high, being greater than 80% when 100 ng of each substance was added per tube, except for DM (74.1%). The stability of E3810 and its four metabolites was evaluated and the following results were obtained: (1) when samples were centrifuged within 20 min after collection, there was no loss of E3810 or its metabolites; (2) when 100 microliters of a 1% aqueous solution of diethylamine was added within 20 min after plasma isolation, there was no loss of E3810 or its metabolites; and (3) there were no stability problems during storage for a period of 10 months at -20 degrees C.


Assuntos
Benzimidazóis/sangue , Inibidores da Bomba de Prótons , 2-Piridinilmetilsulfinilbenzimidazóis , Benzimidazóis/farmacocinética , Cromatografia Líquida de Alta Pressão , Meia-Vida , Humanos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Omeprazol/análogos & derivados , Rabeprazol , Espectrofotometria Ultravioleta
10.
Biol Pharm Bull ; 16(3): 319-21, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8364482

RESUMO

Bioavailability of phytonadione was investigated after oral administration to beagle dogs. The administrations of phytonadione in a surfactant solution (preparation a) and in an oleic acid solution (preparations b) greatly increased the bioavailability of phytonadione. The AUCs of preparations a and b were about 2.5 times larger than those of commercially available tablets A and C. This result well corresponded to the results of the dissolution test previously reported. The absorption of phytonadione from the gastro-intestinal tract was affected by food and the bioavailability was largely increased under non-fasted conditions. However, a large scatter was observed in the data, and it was found that the evaluation of the bioavailability of phytonadione preparations could not be done in non-fasted animals.


Assuntos
Vitamina K 1/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Cães , Excipientes , Absorção Intestinal/efeitos dos fármacos , Masculino , Ácidos Oleicos/farmacologia , Solubilidade , Soluções , Tensoativos/farmacologia , Comprimidos , Vitamina K 1/administração & dosagem
11.
J Chromatogr ; 584(2): 261-6, 1992 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-1484111

RESUMO

A gas chromatographic-mass spectrometric method was developed to determine eperisone hydrochloride, 4'-ethyl-2-methyl-3-piperidinopropiophenone hydrochloride, in human plasma over the concentration range 0.2-40 ng/ml. Excellent sensitivity was achieved by selection of a favorable fragment ion, m/z 98, of eperisone and reduction of heat decomposition of eperisone by using a splitless injector and a shortened capillary column. The method described here allows the determination of plasma concentrations as low as 0.2 ng/ml, the concentration attained 6 h after a single oral administration of 50 mg. At eperisone hydrochloride concentrations higher than 0.5 ng/ml, the mean inter-day variation of accuracy of the assay was less than 12%.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Relaxantes Musculares Centrais/sangue , Propiofenonas/sangue , Calibragem , Humanos , Valores de Referência , Reprodutibilidade dos Testes
12.
J Pharm Sci ; 80(12): 1153-6, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1815074

RESUMO

In a previous study, we developed a multiple-unit type of oral floating dosage system, which is a new type of floating pill composed of both an effervescent layer and a swellable membrane layer coated on sustained-release pills. The system was shown to have excellent floating ability and sustained-release characteristics in vitro, irrespective of the pH and viscosity of the medium. In the present study, the floating ability and the sustained-release characteristics of the system in the gastrointestinal tract have been evaluated in vivo. In beagle dogs and humans in the fed state, most of the new type of pills containing barium sulfate were floating in the stomach at 10 min, and they kept floating for at least 3 h after administration (observed by periodic X-ray photographs), while some control pills without the effervescent layers were already transited into the small intestine by 3 h. Moreover, in order to evaluate the sustained-release characteristics of the drug from the new type of floating pills, p-aminobenzoic acid (PABA), with a limited absorption site, and isosorbide dinitrate (ISDN), with wide absorption sites in the gastrointestinal tract, were employed as model drugs. Floating pills of the new type, with the same sustained-release rate as that of non-floating pills (control pills) were prepared. In beagle dogs in the fed state, the new type of floating pills containing PABA showed higher plasma PABA levels at 5 and 6 h after dosing and 1.61 times greater AUC than the control pills.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ácido 4-Aminobenzoico/administração & dosagem , Dinitrato de Isossorbida/administração & dosagem , Modelos Biológicos , Ácido 4-Aminobenzoico/sangue , Administração Oral , Animais , Preparações de Ação Retardada , Cães , Esvaziamento Gástrico , Humanos , Dinitrato de Isossorbida/sangue , Radiografia , Estômago/diagnóstico por imagem
13.
Chem Pharm Bull (Tokyo) ; 37(12): 3359-62, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2632084

RESUMO

Nasal absorption of secretin in rats was enhanced in an acid solution and the maximum absorption was observed at a sodium chloride solution molarity of 0.462. In order to predict how changes in the secretin molecule would affect its absorption through the nasal mucosa independently of structural changes in the epithelial membrane, an artificial membrane permeation test was conducted, and the apparent partition coefficient between octanol and a test solution was determined. The concentration of secretin was measured using high performance liquid chromatography. The amount of secretin that permeated through an artificial membrane was hardly affected by changes in pH, which suggest that the size of the secretin molecule was not changed. The apparent partition coefficient, however, increased as the pH of the test solution rose from 3.81 to 7.0, which suggested that the hydrophobicity of secretin was enhanced. In relation to the osmolarity of the test solution, the amount of permeation was hardly affected by the concentration of sodium chloride, but the partition coefficient increased with the concentration of the sodium chloride solution. It was supposed that the size of the secretin molecule was not changed in spite of the increasing hydrophobicity, and the nasal absorption of secretin at a sodium chloride molarity of 0.462 was dependent on a change in the epithelial cells. When sorbitol was used as an osmoregulatory agent, the apparent partition coefficient hardly varied as the osmolarity of the solution was increased, whereas the amount of permeation decreased, and these findings reflected the nasal absorption in rats.


Assuntos
Mucosa Nasal/metabolismo , Secretina/farmacocinética , Absorção , Animais , Fenômenos Químicos , Físico-Química , Concentração de Íons de Hidrogênio , Membranas Artificiais , Concentração Osmolar , Permeabilidade , Ratos , Solubilidade
16.
J Pharm Sci ; 76(9): 695-8, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11002804

RESUMO

Nasal absorption of secretin in rats was enhanced in an acid solution, and the maximum absorption was observed at a sodium chloride solution molarity of 0.462. In order to examine reasons for the variation of absorbability caused by the change of pH and osmolarity in secretin preparations, both a pretreatment study, in which the nasal mucosa was treated with placebo prior to the administration of a secretin preparation, and a histological study were conducted in rats. The nasal absorption of secretin was determined by measuring the increased secretin of pancreatic juice. Similar profiles of nasal absorption, both after intranasal administration of secretin preparations and as a result of pretreatment effects, were obtained in studies of the effects of pH and osmolarity. However, in the pH-effect study, the absorption with the use of active preparations was observed to be significantly larger than that with the pretreatment effect below a pH of 4.79, and significantly smaller than that with the pretreatment effect at a pH of 7 to 8. The results of histological studies revealed structural changes of the epithelial cells of the nasal mucosa at pH 2.94, and shrinkage of epithelial cells was observed at a sodium chloride solution molarity of 0.462.


Assuntos
Mucosa Nasal/metabolismo , Secretina/farmacocinética , Absorção , Animais , Concentração de Íons de Hidrogênio , Masculino , Concentração Osmolar , Ratos , Ratos Sprague-Dawley
17.
J Pharm Sci ; 76(4): 286-8, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3598885

RESUMO

The present study was an attempt to develop a new dosage form of cinnarizine, which is slightly soluble in water, using lipid as a vehicle. The solubility of cinnarizine in several organic solvents was determined. It was found that cinnarizine dissolved well in oleic and linoleic acids. The bioavailability of cinnarizine from the oral administration of an oleic acid solution in a hard capsule was investigated and compared with that of a cinnarizine tablet, using beagle dogs. When cinnarizine was administered in a capsule, the bioavailability was greatly enhanced [i.e., the maximum concentration (Cmax) and AUC values were 2.9 and 4.0 times larger than those of a cinnarizine tablet, respectively]. Meanwhile, the tmax value (the time to reach Cmax) was unchanged. The absorption of cinnarizine from an oleic acid solution was considered to depend on the action of bile salts. This was supported by the results of a dissolution test using a bile salts solution as the dissolution test medium.


Assuntos
Cinarizina/metabolismo , Ácidos Oleicos , Animais , Disponibilidade Biológica , Cinarizina/administração & dosagem , Cães , Absorção Intestinal , Masculino , Ácido Oleico , Veículos Farmacêuticos , Solubilidade , Solventes
20.
J Pharm Sci ; 75(4): 391-4, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3723361

RESUMO

The present investigation is concerned with an improvement of the bioavailability of cinnarizine by administering its beta-cyclodextrin complex together with another compound which competes with the beta-cyclodextrin molecule in complex formation in aqueous solution (competing agent). The bioavailability of cinnarizine on oral administration of the cinnarizine-beta-cyclodextrin inclusion complex was enhanced by the simultaneous administration of DL-phenylalanine as a competing agent, e.g., the AUC was 1.9 and 2.7 times as large as those of the cinnarizine-beta-cyclodextrin complex alone and cinnarizine alone, respectively. The enhancement of AUC and Cmax completely depended on the dose of DL-phenylalanine. It was found from these results that DL-phenylalanine acted as a competing agent in the GI tract and the minimum effective dose required of DL-phenylalanine might be 1 g for 50 mg of cinnarizine in the cinnarizine-beta-cyclodextrin complex. Evaluating the competing effect of DL-phenylalanine in vitro using an absorption simulator, it was found that the decreased penetration rate of cinnarizine through the artificial lipid barrier with addition of beta-cyclodextrin was restored with the addition of DL-phenylalanine.


Assuntos
Cinarizina/metabolismo , Fenilalanina/metabolismo , beta-Ciclodextrinas , Administração Oral , Animais , Ligação Competitiva , Disponibilidade Biológica , Ciclodextrinas , Cães , Absorção Intestinal , Fatores de Tempo
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