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1.
J Mass Spectrom ; 51(9): 742-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27466738

RESUMO

The genuineness of fruit juices and purees is regulated by guidelines of European Fruit Juice Association. Nevertheless, the addition of peach puree to apricot puree is considered the most common adulteration, very difficult to discover. In this study, the composition in free and conjugated polyphenols of apricot and peach purees was performed by target and untarget approaches with Q-Exactive(™) quadrupole-Orbitrap mass spectrometer. Apricot purees showed a higher polyphenol content than those of peaches. Between target coumpounds, chlorogenic acid, rutin, catechin and smaller quantities of hyperoside and kaempferol-3-rutinoside were found in both purees. Apricot puree was also found to contain epicatechin and procianidin B2, absent in peach puree. Peach puree was found to contain small amounts of kaempferol-3-glucoside, absent in apricot. In order to identify untarget polyphenols, data obtained by ultra-high pressure liquid chromatography tandem mass spectrometry analysis were processed with Thermo Scientific automated label-free differential expression software (sieve(™) 2.1 software). Three hydroxycinnamic acid conjugates and a procyanidin were identified and confirmed by tandem mass spectrometry spectra. Some compounds of interest found from differential analysis had a putative identification, while others remained unidentified. The high-resolution mass spectrometry approach using Q-Exactive(™) quadrupole-Orbitrap mass spectrometer could be an important and powerful tool for determination of new biomarkers in fruits and vegetables. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Espectrometria de Massas/métodos , Polifenóis/análise , Prunus armeniaca/química , Prunus persica/química , Análise de Componente Principal , Software
3.
Neuropharmacology ; 38(9): 1281-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10471081

RESUMO

Treatment with diazepam (25 mg/kg; p.o., twice-daily for 17 days) induced tolerance to the anticonvulsant effect of diazepam against bicuculline-induced convulsions in mice. Cross-tolerance was observed to the anticonvulsant action of clonazepam, imidazenil but not abecarnil. While substitution of clonazepam (12 mg/kg; p.o., twice-daily for 15 days) for diazepam did not affect tolerance to diazepam, substitution of imidazenil (17 mg/kg; p.o., twice-daily for 15 days) for diazepam significantly increased sensitivity to the anticonvulsant effect of diazepam, although tolerance was not abolished. Tolerance to diazepam progressively decreased either after suspension of diazepam administration or replacement treatment with abecarnil (20 mg/kg; p.o., twice-daily). Complete recovery of diazepam efficacy was detected after 8 and 15 days of administration of abecarnil and vehicle, respectively. Binding experiments using [3H]-flumazenil showed that Kd values did not differ among treatment groups. A significant decrease in Bmax (-42%) was observed in the cortex of diazepam-tolerant mice whether or not also treated with imidazenil and clonazepam. Conversely, chronically diazepam-treated mice, that further received abecarnil for either 8 or 15 days or vehicle for 15 days showed Bmax values similar to those of vehicle-treated mice never exposed to diazepam. Results suggest that repeated abecarnil administration to diazepam-tolerant mice can facilitate re-adaptation of receptors to the diazepam-free state. It is proposed that replacement therapy with abecarnil after long-term treatment with conventional benzodiazepines (BDZs) may provide a novel approach for reducing tolerance to their anticonvulsant effects.


Assuntos
Anticonvulsivantes/farmacologia , Carbolinas/farmacologia , Córtex Cerebral/efeitos dos fármacos , Diazepam/uso terapêutico , Tolerância a Medicamentos , Animais , Anticonvulsivantes/uso terapêutico , Benzodiazepinas/farmacologia , Bicuculina/antagonistas & inibidores , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Córtex Cerebral/metabolismo , Clonazepam/farmacologia , Interações Medicamentosas , Flumazenil/farmacologia , Imidazóis/farmacologia , Ligantes , Masculino , Camundongos , Receptores de GABA-A/metabolismo , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Trítio
4.
Neuroreport ; 10(3): 517-21, 1999 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-10208582

RESUMO

Tolerance to the rewarding properties of morphine was investigated in mice using a new conditioned place preference (CPP) procedure. Four pairings of morphine with specific environmental cues induced a significant CPP for the drug-paired cues. Further opiate conditioning trials in the presence of the same environmental cues revealed no change in the drug-induced CPP on repeated test sessions. Subsequent exposure of the same animals to conditioning trials by pairing morphine with a set of novel environmental cues showed that the opiate was still able to produce a CPP in mice treated with a total of 16 morphine injections. The present CPP paradigm may prove useful to investigate tolerance to the rewarding properties of drugs of abuse.


Assuntos
Comportamento de Escolha/fisiologia , Condicionamento Psicológico/fisiologia , Meio Ambiente , Morfina/farmacologia , Animais , Sinais (Psicologia) , Tolerância a Medicamentos , Masculino , Camundongos , Camundongos Endogâmicos , Recompensa
5.
Naunyn Schmiedebergs Arch Pharmacol ; 355(5): 589-94, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9151297

RESUMO

The effect of repeated morphine administration on conditioned place preference (CPP) using a novel treatment schedule, i.e., drug treatment was always contingent with the conditioned environmental stimuli, was investigated. We also examined whether changes in the mu- and kappa-opioid receptor binding occurred in the brain of morphine-treated animals. Intraperitoneal (i.p.) administration of morphine (2 and 10 mg/kg) induced a place preference after 8 daily conditioning trials (4 morphine injections on alternate trials), the level of preference being the same with the two doses of the opiate. No change in place preference was observed in the morphine-treated rats at 2 mg/kg, when animals were further trained up to a total of 32 conditioning trials (16 morphine injections). Conversely, after 20 conditioning trials (10 morphine injections), a stronger CPP response developed in the morphine-treated rats at 10 mg/kg. Signs of morphine withdrawal were never detected in morphine-treated rats during the experiment. Loss of body weight (index of opiate dependence) was not observed either 24 h or 48 h after the last morphine administration. mu- and kappa-opioid receptor density and affinity were not affected by repeated morphine administrations at either dose. The results demonstrate that no tolerance develops to the rewarding properties of morphine. Indeed, a sensitisation effect may occur at increasing doses of the opiate. Furthermore, changes in the rewarding effect of morphine are not dependent upon alterations in opioid receptors involved in the reinforcing mechanisms.


Assuntos
Benzenoacetamidas , Dependência de Morfina , Morfina/toxicidade , Entorpecentes/toxicidade , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Tolerância a Medicamentos , Ala(2)-MePhe(4)-Gly(5)-Encefalina , Encefalinas/metabolismo , Injeções Intraperitoneais , Masculino , Morfina/administração & dosagem , Morfina/metabolismo , Dependência de Morfina/fisiopatologia , Entorpecentes/administração & dosagem , Entorpecentes/metabolismo , Pirrolidinas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Opioides kappa/agonistas , Receptores Opioides kappa/efeitos dos fármacos , Receptores Opioides kappa/metabolismo , Receptores Opioides mu/agonistas , Receptores Opioides mu/efeitos dos fármacos , Receptores Opioides mu/metabolismo
6.
Naunyn Schmiedebergs Arch Pharmacol ; 354(5): 612-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8938660

RESUMO

Development of tolerance and dependence has been reported to occur upon chronic administration of traditional benzodiazepines (BZDs). We compared the effect of chronic treatment with abecarnil, a beta-carboline derivative with high affinity for central BDZ receptors, and diazepam, the BDZ prototype, in mice. After acute administration, abecarnil was as potent and effective as diazepam in protecting from bicuculline-induced convulsion. The time-course analysis of two peak equieffective doses of abecarnil (1.9 mg/kg p.o.) and diazepam (2.7 mg/kg p.o.) showed a similar duration of action. The anticonvulsant potency of diazepam was reduced in mice given chronic diazepam (25 mg/kg p.o., 2 times a day for 17 days). No tolerance to abecarnil was apparent when the drug was administered for the same period using a comparable dose (20 mg/kg p.o.). Severe symptoms of precipitated withdrawal were observed upon administration of the BDZ partial inverse agonist Ro 15-3505 in mice treated chronically with diazepam but not abecarnil. In mice made tolerant to diazepam, maximum [3H]-flumazenil binding sites were reduced in both cerebral cortex (-50%) and cerebellum (-55.2%). No changes in [3H]-flumazenil binding were measured in chronic abecarnil-treated mice. These data indicate that abecarnil possesses a very low tolerance/dependence liability and does not affect BZD receptor density after chronic administration.


Assuntos
Ansiolíticos/farmacologia , Anticonvulsivantes/farmacologia , Carbolinas/farmacologia , Diazepam/farmacologia , Animais , Ansiolíticos/efeitos adversos , Anticonvulsivantes/efeitos adversos , Bicuculina , Sítios de Ligação , Carbolinas/efeitos adversos , Convulsivantes , Diazepam/efeitos adversos , Relação Dose-Resposta a Droga , Tolerância a Medicamentos , Masculino , Camundongos , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Síndrome de Abstinência a Substâncias/etiologia
7.
Br J Pharmacol ; 117(4): 647-52, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8646409

RESUMO

1. Development of anticonvulsant tolerance and benzodiazepine (BZD) receptor down-regulation has been reported to occur upon chronic administration of conventional BZDs. We compared the effect of chronic treatment with imidazenil, a new BZD partial agonist, and diazepam in rats. 2. After acute administration, imidazenil was more potent though less effective than diazepam in protecting from bicuculline-induced seizure. The time-course analysis of two peak equieffective doses of imidazenil (2.5 mumol kg-1 p.o.) and diazepam (35 mumol kg-1, p.o.) showed a longer lasting action of the former drug. 3. The anticonvulsant efficacy of diazepam (35 mumol kg-1, p.o.) was reduced in rats given chronic diazepam (35 mumol kg-1 p.o., 3 times a day for 8-15 days). No tolerance to imidazenil (2.5 mumol kg-1, p.o.) was apparent after 130-day administration with imidazenil (2.5 mumol kg-1, p.o., 3 times a day). 4. Plasma levels of imidazenil and diazepam, assessed 30 min after administration, were not changed in chronically treated animals. 5. In rats made tolerant to diazepam, the maximum number of [3H]-flumazenil binding sites were reduced in both cerebral cortex (-36%) and cerebellum (-42%). No changes in [3H]-flumazenil binding were found in chronic imidazenil-treated rats. 6. Specific [3H]-flumazenil binding in vivo was decreased in the forebrain of chronic diazepam- but not of chronic imidazenil-treated animals. 7. These data indicate that imidazenil possesses a very low tolerance potential to its anticonvulsant activity and does not affect BZD receptor density even after prolonged administration.


Assuntos
Anticonvulsivantes/farmacologia , Benzodiazepinas/farmacologia , Regulação para Baixo , Moduladores GABAérgicos/farmacologia , Imidazóis/farmacologia , Receptores de GABA-A/efeitos dos fármacos , Animais , Benzodiazepinas/sangue , Bicuculina/toxicidade , Diazepam/sangue , Diazepam/farmacologia , Tolerância a Medicamentos , Flumazenil/metabolismo , Moduladores GABAérgicos/sangue , Imidazóis/sangue , Masculino , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/metabolismo , Convulsões/induzido quimicamente , Trítio
8.
Br J Pharmacol ; 114(6): 1159-64, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7620705

RESUMO

1. The binding of [3H]-imidazenil, an imidazobenzodiazepine carboxamide, to rat cerebellar membranes was characterized at different temperatures. 2. Specific binding was linear with tissue concentrations and reached maximum after 90, 30 and 5 min incubation at 0, 21 and 37 degrees C, respectively. The binding was of high affinity, specific and saturable; non linear regression and Scatchard analysis of the data was compatible with the presence of a single population of receptor sites with Bmax of 0.74 +/- 0.020, 0.90 +/- 0.011 and 1.0 +/- 0.036 pmol mg-1 protein at 0, 21 and 27 degrees C, respectively. Binding affinity decreased with increasing temperature: Kd were 0.29 +/- 0.051 nM (0 degrees C), 1.0 +/- 0.080 nM (21 degrees C) and 2.4 +/- 0.38 nM (37 degrees C). 3. At all tested temperatures, [3H]-imidazenil binding was reversible and the Kd calculated from the dissociation and association rate constants approximated the equilibrium Kd. 4. In the presence of gamma-aminobutyric acid (GABA), Kd increased 4 fold at 0 degrees C, whereas Bmax increased, albeit slightly, at all temperatures. 5. Benzodiazepines (BZDs), imidazopyridines and methyl-beta-carboline-3-carboxylate (beta CCM) were effective inhibitors of [3H]-imidazenil binding. Conversely, GABAA antagonists, barbiturates, picrotoxin and peripheral BZD receptor ligands were devoid of any activity. 6. Comparing [3H]-imidazenil to [3H]-flumazenil binding in various brain areas, similar densities of recognition sites as well as like regional differences in the distribution of binding sites for both radioligands were observed (cortex = striatum > cerebellum > spinal cord). 7. The present results indicate that [3H]-imidazenil specifically binds to the BZD sites of GABAA receptors. Furthermore, the effects of GABA and temperature differentiate imidazenil from classicalBZDs. It is suggested that the characteristics of imidazenil binding may be relevant to the in vivo pharmacology of the drug.


Assuntos
Benzodiazepinas/metabolismo , Cerebelo/metabolismo , Imidazóis/metabolismo , Receptores de GABA-A/metabolismo , Temperatura , Ácido gama-Aminobutírico/farmacologia , Animais , Cinética , Masculino , Membranas/efeitos dos fármacos , Membranas/metabolismo , Ensaio Radioligante , Ratos , Ratos Endogâmicos , Termodinâmica , Trítio
9.
Psychopharmacology (Berl) ; 115(1-2): 73-8, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7862915

RESUMO

Anxiolytic benzodiazepines have been shown to impair place learning in the Morris water maze. However, a clear-cut demonstration of a direct and specific effect on mnemonic processes has not yet been offered. In the present study, the effects of diazepam on place navigation in the Morris water maze were studied in rats. Three conditions were examined: learning, reversal learning and learning after familiarisation of animals with the maze. In view of the anxiolytic and sedative properties of diazepam, appropriate doses of the drug, i.e. those that produced an anxiolytic effect but no major motor impairment, were initially selected in the water-lick conflict and rotarod tests, respectively. Doses of 2.5 and 5 mg/kg PO increased punished drinking in the water-lick conflict test without significantly decreasing rotarod performance. These doses were then used to assess the effects of diazepam on spatial behaviour. Diazepam, at both doses, impaired place learning in behaviourally naive rats. Such an effect appeared to be transient: diazepam-treated rats eventually reached control performance. Moreover, analysis of the probe trial at the end of training revealed adoption of a spatial strategy to locate the submerged platform. Neither reversal learning nor learning after familiarisation was affected. These results do not replicate previous findings in the Morris water maze and provide some evidence that the diazepam-induced place learning deficit may be primarily anxiolytic in nature.


Assuntos
Diazepam/farmacologia , Aprendizagem/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Animais , Conflito Psicológico , Ingestão de Líquidos/efeitos dos fármacos , Emoções/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Equilíbrio Postural/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Reversão de Aprendizagem/efeitos dos fármacos
10.
Ann N Y Acad Sci ; 695: 314-7, 1993 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-8239303

RESUMO

A large body of experimental data suggests that neurotrophic molecules and/or substances that facilitate their action could be pharmaceutical agents for neurodegenerative pathologies. In particular, it has been demonstrated that nerve growth factor (NGF) exerts a physiological role for forebrain cholinergic neurons, while brain-derived neurotrophic factor (BDNF) seems to play a relevant role in rescuing dopaminergic neurons following damage. In addition, gangliosides are reported to potentiate neurotrophic factor effects in vitro as well as in vivo. In this study we examined the effects of the monosialoganglioside GM1 in different experimental models. The responsiveness of forebrain cholinergic neurons following NGF +/- GM1 was evaluated by assessing choline acetyltransferase (ChAT) activity in hippocampus, septal area and striatum of behaviorally impaired 24-month-old rats. NGF was intracerebroventricularly (i.c.v.) infused for 2 weeks while GM1 was given systemically for 3 weeks, starting from the beginning of NGF infusion. Moreover, the possible protective effects of GM1 were assessed following exposure of cultured cerebellar granule cells and dopaminergic mesencephalic neurons to different doses of 6-OH-DOPA, a metabolite of the dopamine pathway which has excitotoxic properties and has been hypothesized to participate in the pathology of Parkinson's disease. GM1 treatment to aged rats was seen to potentiate the NGF-induced increase of ChAT activity in the striatum ipsilateral to the NGF infusion. Moreover, in the striatum contralateral to the NGF infusion, GM1 increased ChAT activity above the control values, whereas NGF treatment alone did not affect enzymatic activity. GM1 treatment of cerebellar granule cells and mesencephalic neurons counteracted the dose- and time-dependent neurotoxicity of 6-OH-DOPA. These data support the notion that GM1 might prove useful in treating those pathological conditions where trophic factor deficits and/or excitotoxin-related toxicity play an important role.


Assuntos
Encéfalo/enzimologia , Colina O-Acetiltransferase/metabolismo , Gangliosídeo G(M1)/farmacologia , Fatores de Crescimento Neural/farmacologia , Envelhecimento/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Animais , Encéfalo/efeitos dos fármacos , Ventrículos Cerebrais/efeitos dos fármacos , Ventrículos Cerebrais/fisiologia , Gangliosídeo G(M1)/administração & dosagem , Gangliosídeo G(M1)/uso terapêutico , Humanos , Injeções Intraventriculares , Fatores de Crescimento Neural/administração & dosagem , Fatores de Crescimento Neural/uso terapêutico , Especificidade de Órgãos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia
11.
Allerg Immunol (Paris) ; 25(4): 141-4, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8489694

RESUMO

In this paper a simple conceptual model is introduced in order to predict the atmospheric pollen concentration threshold above which pollinotics show allergic symptoms. In addition, the range of the pollen sampler with respect to the local and remote emission of pollen grains, produced by the vegetation in its flowering phase, is highlighted. Two different pollen types have been considered; their emission in the atmosphere takes place in two periods of the year, which greatly differ both in climatological respect and concerning the atmospheric of mixing particles. The data analysis is carried using a methodological approach, taking into account phenological, aerobiological and meteorological parameters.


Assuntos
Pólen , Ar , Previsões , Conceitos Meteorológicos , Modelos Teóricos , Especificidade da Espécie , Árvores
14.
Arzneimittelforschung ; 42(11A): 1394-6, 1992 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1492859

RESUMO

The pharmacokinetic properties of dihydroergocristine (DHEC, CAS 17479-19-5) were investigated in rats using a specific radioimmunoassay technique specific for non-metabolized drugs. DHEC, administered intravenously at the dose of 6 mg/kg, showed a plasma profile conforming to an open two-compartment pharmacokinetic model with a long terminal half-life (t1/2 = 13.6 h). DHEC kinetics after oral administration (6 mg/kg) showed two peaks. The first peak (C = 37 micrograms/l) occurred at the first collection point (0.5 h) indicating a quick absorption of the drug. The second peak (C = 34 micrograms/l) occurred at 2 h and may be considered an indication of an enterohepatic cycle. A long terminal half-life (t1/2 = 18.1 h) was observed. An extensive biotransformation of DHEC was indicated by an almost complete absence of unchanged drug in the urine and a high systemic clearance (2.65 l.h-1 x kg-1). A large volume of distribution (52 l.kg-1) was calculated.


Assuntos
Di-Hidroergotoxina/farmacocinética , Administração Oral , Animais , Di-Hidroergotoxina/administração & dosagem , Meia-Vida , Injeções Intravenosas , Masculino , Radioimunoensaio , Ratos , Ratos Sprague-Dawley
15.
Arzneimittelforschung ; 42(11A): 1397-9, 1992 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-1492860

RESUMO

This paper reports the pharmacokinetics of three dihydroergocristine (DHEC, CAS 17479-19-5) oral formulations in six volunteers. In a randomized crossover trial the volunteers received 6 mg of the drug (1 tablet of 6 mg; 3 ml of drops containing 2 mg/ml; 1 single-dose bottle containing 6 mg); radioimmunoassay was used for the determination of the unchanged drug plasma levels. DHEC shows a plasma profile according to a 3-compartment pharmacokinetic model with a long half-life and high distribution volume. The analysis of AUC0-infinity, Cmax, tmax, and other pharmacokinetic parameters shows that the three formulations investigated are practically bioequivalent.


Assuntos
Di-Hidroergotoxina/farmacocinética , Administração Oral , Adulto , Meia-Vida , Humanos , Masculino , Radioimunoensaio
17.
Cephalalgia ; 11(3): 117-21, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1909603

RESUMO

Dihydroergokryptine has been evaluated in the prophylaxis of headache attacks in patients with migraine without aura. The study was controlled vs dihydroergotamine with a double-blind crossover design. After a 1-month run-in period, 30 patients were randomized into two groups and submitted to 4 months treatment with dihydroergokryptine 10 mg b.i.d. or dihydroergotamine (controlled release) 5 mg b.i.d. The treatment was repeated in crossover after 2 months washout. The clinical patients' evaluation was determined by monthly Pain Total Index recording, headache days/month and analgesic consumption. The patients were considered responsible when Pain Total Index decreased by 50% or more in 1 or more months of each treatment period; otherwise the patients were considered unresponsive. The response rate to dihydroergokryptine was 66% while 48% of cases were responsive to dihydroergotamine. The response rate to both treatments was 41%, while 26% did not respond to either treatment. Seven cases unresponsive to dihydroergotamine responded positively to dihydroergokryptine while two cases only, resistant to dihydroergokryptine, responded positively to dihydroergotamine. Three cases dropped out during treatment with dihydroergotamine due to gastric pain and nausea, while they did not show any side effects during dihydroergokryptine therapy. During treatment with dihydroergokryptine there was one case of skin rash which disappeared after drug withdrawal. In conclusion, dihydroergokryptine appears to be an effective drug for the prophylaxis of migraine attacks.


Assuntos
Di-Hidroergotamina/uso terapêutico , Di-Hidroergotoxina/uso terapêutico , Transtornos de Enxaqueca/prevenção & controle , Adulto , Analgésicos/uso terapêutico , Di-Hidroergotamina/efeitos adversos , Di-Hidroergotoxina/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/fisiopatologia , Fatores de Tempo
18.
Arzneimittelforschung ; 41(7): 689-91, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1772454

RESUMO

The pharmacokinetic properties of alpha-dihydroergocryptine methanesulphonate (alpha-DHEK, CAS 19467-62-0) were investigated in rat using a radioimmunoassay technique for nonmetabolized drug. alpha-DHEK, intravenously administered at the dose of 6 mg/kg, showed a plasma profile according to an open 3-compartment pharmacokinetic model with a long half-life (about 7.56 h). The kinetics of alpha-DHEK after oral administration (6 mg/kg) showed two peaks; the second peak at 8 h was probably due to an enterohepatic cycle. The disposition of alpha-DHEK consisted in a fast absorption and a slow elimination (t1/2el about 6.78 h). The alpha-DHEK was largely metabolized as results from the complex metabolite profile in body fluids and from very low urinary elimination of unchanged drug.


Assuntos
Di-Hidroergotoxina/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Di-Hidroergotoxina/administração & dosagem , Meia-Vida , Injeções Intravenosas , Masculino , Modelos Biológicos , Radioimunoensaio , Ratos
19.
Aging (Milano) ; 3(2): 147-52, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1911903

RESUMO

The memory retention abilities of aged rats fed different diets were assessed in two different avoidance tasks. The standard passive avoidance procedure revealed an age-related memory impairment in old rats fed a standard diet (ST), whereas old rats fed a hypocaloric diet (HY) behaved similarly to young animals. To clarify whether this deficit could be attributed only to cognitive decay and not other factors, such as the tendency of old rats to prefer darkness to light more than young and adult animals, a multiple passive avoidance task was performed. This test offers rats the possibility to escape to a dark chamber in which they have never been shocked, and thus provides a means of checking factors other than memory retention abilities. All the old rats showed a more marked preference to escape to darkness compared to young and adult animals. However, senescent animals fed a ST diet had poor memory retention abilities compared to aged animals fed the HY diet, and young and adult rats. The results of this test confirmed the findings of the standard passive avoidance task.


Assuntos
Envelhecimento/psicologia , Privação de Alimentos/fisiologia , Memória/fisiologia , Animais , Aprendizagem da Esquiva/fisiologia , Dieta , Ingestão de Energia , Masculino , Ratos
20.
Drugs Exp Clin Res ; 17(6): 309-12, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1769319

RESUMO

The pharmacokinetic profile of a single dose (6 mg/kg) of alpha-dihydroergokryptine (alpha-DHEK) was established after oral administration in monkeys using a radio-immunoassay technique for non-metabolized drug. alpha-DHEK showed a plasma profile according to an open three-compartment pharmacokinetic model with a long half-life (mean = 5.787 h). The disposition of alpha-DHEK involves a fast absorption, a slow distribution phase and a slow elimination phase. alpha-DHEK showed an high total clearance and distribution volume; the drug is largely metabolized, as concluded from the very low urinary excretion.


Assuntos
Administração Oral , Di-Hidroergotoxina/farmacocinética , Animais , Di-Hidroergotoxina/sangue , Di-Hidroergotoxina/urina , Feminino , Macaca fascicularis , Masculino
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