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1.
Folia Morphol (Warsz) ; 80(4): 923-934, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33084014

RESUMO

BACKGROUND: Description of the nasopalatine canal (NPC) is important for planning surgical treatment and comprehension of the morphology and pathogenesis of lesions that occur in the anterior maxilla. The goal of this study was to analyse the dimensions and anatomic characteristics of the NPC on cone-beam computed tomography (CBCT) scans, to determine the incidence of anatomical variation; and to assess the correlations of these variables with age, gender, and dental status. MATERIALS AND METHODS: A total of 320 individual CBCT images were included. Reformatted sagittal, coronal and axial slices were evaluated. Sagittal images were used for measurements of the NPC and to classified shape and direction-course of the NPC. Coronal images were used to analyse the NPC division levels and axial images were used to detect the number of palatal and nasal opening. RESULTS: The mean NPC length was 11.45 ± 2.50 mm; statistically significant differences were detected between males and females (p < 0.05). Mean nasopalatine angle was 76.26 ± 8.12°; significant differences were detected in sagittal and coronal classifications. The most common canal was: funnel-shaped (29%), slanted-curved direction-course (53.1%), middle third division level (43.1%), and one incisive foramen with two Stenson's foramina (1-2) (77.2%). CONCLUSIONS: The current study ensures new findings on the literature concerning the description of the anatomical structure of the canal. Also, the study highlights a significant variability in the anatomy and morphology of the NPC. Therefore, three-dimensional analysis of this structure is important for facilitating surgical management and preventing possible complications in this area.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Palato , Feminino , Humanos , Masculino , Maxila/diagnóstico por imagem , Nariz , Palato/diagnóstico por imagem , Estudos Retrospectivos
2.
Phys Chem Chem Phys ; 19(38): 26121-26131, 2017 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-28929146

RESUMO

Peripherally and non-peripherally terminal alkynyl substituted manganese phthalocyanines (MnPc) were synthesized and characterized and then used as functional materials in modified electrodes. MnPcs were substituted with alkynyl groups, which are reactive moieties in click electrochemistry (CEC) reactions. Mn(iii) cations were incorporated into the cavity of the Pc ring in order to increase the redox activity of the complexes. Electrochemical characterizations of the complexes were determined by voltammetric and in situ spectroelectrochemical measurements in order to determine their possible technological applications. MnPc complexes illustrated five redox couples and these redox couples were assigned as [Cl-MnIIIPc2-]/[Cl-MnIIPc2-]1-, [Cl-MnIIPc2-]1-/[Cl-MnIPc2-]2-, [Cl-MnIPc2-]2-/[ Cl-MnIPc3-]3-, and [Cl-MnIIIPc2-]/[Cl-MnIIIPc1-]1+ redox processes. The position of the substituents affected the mechanism of the redox reactions and influenced the tendency to react with the molecular oxygen. Moreover, changing the position of the substituents slightly influenced the peak potentials and reversibility of the redox processes. For the applications, modified electrodes (ITO/PANI-N3-MnPc and GCE/PANI-N3-MnPc) were constructed with CEC reaction between azido functionalized polyaniline (PANI-N3) and terminally alkynyl substituted MnPcs and these electrodes. Voltammetric characterizations of the modified electrodes illustrated suitable redox activity and conductivity for the practical applications. Finally, the GCE/PANI-N3-MnPc electrode was tested as a potential electrocatalyst for water splitting reaction. Although the GCE/PANI-N3-MnPc electrode did not catalyze the hydrogen evolution reaction (HER), it significantly catalyzed the oxygen evolution reaction (OER) in aqueous solution.

3.
Hippokratia ; 20(4): 368-373, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29416312

RESUMO

BACKGROUND: This study investigated the relationship between the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) values with oxidative stress in active Crohn's disease (CD) patients. We investigated whether these parameters were useful for follow-up assessments of CD activity. METHODS: Forty-nine patients with a confirmed diagnosis of CD (24 active and 25 inactive) and 38 control subjects were enrolled in the study. We measured serum activity of superoxide dismutase (SOD) using an enzyme-linked immunosorbent assay (ELISA) and malondialdehyde (MDA) levels using a spectrophotometric method. Neutrophil, lymphocyte and platelet counts were recorded, and the NLR and PLR values were calculated from these parameters. RESULTS: Patients with active CD exhibited significantly higher serum levels of MDA (p =0.007), NLR (p =0.034), and PLR (p =0.026) than inactive CD patients. Receiver operating characteristic (ROC) curve analysis demonstrated that the optimum cut-off values of MDA, NLR, and PLR based on the differences between active and inactive patients were 0.14 µmol/L, 2.58, and 192.26, respectively. The NLR value increased in active patients with elevated MDA levels as a dependent variable (B: 0.422, p =0.029). CONCLUSIONS: We suggest the use of MDA, PLR, and NLR values as a noninvasive test to evaluate disease activity in CD patients. NLR values may also reflect the presence of oxidative stress, and this value may be efficient and useful in determining CD activity. Hippokratia 2016, 20(4): 268-273.

4.
J Oral Rehabil ; 41(11): 822-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25040179

RESUMO

Halitosis is described as offensive breath caused by various factors such as periodontal diseases, bacterial coating of tongue, systemic disorders and different types of foods. Pseudohalitosis is a situation that patients complain of oral malodor even though they do not have offensive odour. The purpose of this study was to compare the relationships between social anxiety estimations and both pseudohalitosis and genuine halitosis cases. Liebowitz Social Anxiety Scale (LSAS) and questionnaire regarding halitosis were applied to 100 participants. Halitosis was determined using organoleptic method, gas chromatography and portable sulphur monitor. anova test and 2-tailed Spearman's rank-order correlation coefficient were used to determine the differences and relations between groups. With reference to LSAS, 62% of participants had anxiety. Among these patients, 98% had genuine halitosis (P < 0·05). The mean measurements of VSC values were 248·65 ppm in halimeter, 298·02 ppm of H2 S, 95·33 ppm of CH3 SH and 47·00 ppm of (CH3 )2 S in gas chromatography. Halitosis was present in 90% of participants, and it was absent in 10% by organoleptic assessment. There was a significant correlation between organoleptic and halimeter measurements. Moreover, statistically significant relationship was detected between anxiety and halitosis. Genuine halitosis patients exhibit social anxiety, so it can be said that there is a causal relationship between halitosis and anxiety. Comparison of the results of objective measurements (sulphur monitor, gas chromatography, organoleptic method) was statistically significant; therefore, it can be said that these methods can be used in diagnosis of halitosis with high accuracy.


Assuntos
Transtornos de Ansiedade/psicologia , Halitose/psicologia , Adulto , Transtornos de Ansiedade/etiologia , Testes Respiratórios/métodos , Cromatografia Gasosa , Feminino , Halitose/complicações , Halitose/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
5.
J Neurosci Res ; 66(4): 674-8, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11746387

RESUMO

Pentylenetetrazol-induced seizures in rats lead to the breakdown of the blood-brain barrier. We compared the disruption of the blood-brain barrier during epileptic seizure in untreated rats and in rats treated with vitamin E or selenium. The rats were supplemented with nontoxic doses of sodium selenite (4 pp) in drinking water for 3 months, or vitamin E (70 mg/kg) was given intraperitoneally for 30 min before the pentylenetetrazole injection. Evans-blue was used as a blood-brain barrier tracer and was given intravenously at a dose of 4 ml/kg of a 2% solution. The rats were divided into four experimental groups. Group I: control (n = 24); Group II: pentylenetetrazole-induced seizure (n = 12); Group III: vitamin E injected + seizure (n = 12); Group IV: Selenium supplemented + seizure (n = 12). The rats subjected to epileptic seizures showed Evans-blue albumin extravasations especially in the thalamic nuclei, brainstem, occipital, and frontal cortex. Mean values for Evans-blue dye were found to be 0.28 +/- 0.04 mg % brain tissue in control rats and 1.6 +/- 0.2 mg % brain tissue after epileptic seizures (P < 0.01). The magnitude of distribution of the blood-brain barrier during epileptic seizures was significantly less in rats treated with vitamin E or selenium. The mean value for Evans-blue dye was found to be 1.2 +/- 0.1 mg % brain tissue in selenium supplemented rats and 1.2 +/- 0.1 mg % brain tissue in vitamin E injected rats after epileptic seizures. This difference between treated and untreated animals was found to be significant (P < 0.05). The findings of the present study suggest that free radicals contribute to disruption of the blood-brain barrier during pentylenetetrazol-induced seizures.


Assuntos
Antioxidantes/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Epilepsia/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Selênio/farmacologia , Vitamina E/farmacologia , Albuminas/farmacocinética , Animais , Barreira Hematoencefálica/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Corantes/farmacocinética , Convulsivantes/farmacologia , Endotélio Vascular/metabolismo , Epilepsia/metabolismo , Epilepsia/fisiopatologia , Azul Evans/farmacocinética , Extravasamento de Materiais Terapêuticos e Diagnósticos/tratamento farmacológico , Extravasamento de Materiais Terapêuticos e Diagnósticos/metabolismo , Extravasamento de Materiais Terapêuticos e Diagnósticos/fisiopatologia , Feminino , Radicais Livres/antagonistas & inibidores , Radicais Livres/metabolismo , Pentilenotetrazol/farmacologia , Ratos , Ratos Wistar
6.
Pharmacol Res ; 44(3): 209-12, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11529687

RESUMO

The interrelationship between the breakdown of the blood-brain barrier according to the Evans-blue passage and an abrupt increase in blood pressure (DeltaP) was studied in rats subjected to adrenaline-induced acute hypertension and also pentylenetetrazol-induced seizures. Arterial blood pressure was increased by adrenaline, then immediately i.v. nifedipine was injected and subsequently decreased to the control value in the acute hypertensive group. Arterial blood pressure was increased by pentylenetetrazol, then immediately GABA (gamma-aminobutiric acid) was injected and the blood pressure was decreased to the control value in the seizure group. The animals were divided into five groups. Group I: control; Group II: acute hypertension; Group III: acute hypertension + nifedipine; Group IV: seizure; Group V: seizure + GABA. The Evans-blue dye content was found to be 0.25 +/- 0.01 mg% in the whole brain in the control animals, and 0.803 +/- 0.1 mg% in the acute hypertensive group. This difference between these groups was found to be significant: P< 0.01. In the nifedipine group (Group III) the Evans-blue content was 0.30 +/- 0.1 mg% in the whole brain; and there was no significant difference between control values and nifedipine-treated animals (P> 0.5). The Evans-blue content was 1.6 +/- 0.2 mg% in the whole brain during seizure, and decreased to 0.36 +/- 0.1 mg% after GABA injection was administered. There was also no significant difference between the control value and the GABA-treated animals (P> 0.5). These results have shown that an abrupt increase in blood pressure (DeltaP) did not change the blood-brain barrier permeability in both acute hypertension and seizures.


Assuntos
Pressão Sanguínea/fisiologia , Barreira Hematoencefálica/fisiologia , Epilepsia , Hipertensão , Doença Aguda , Agonistas Adrenérgicos/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Permeabilidade Capilar/efeitos dos fármacos , Permeabilidade Capilar/fisiologia , Epilepsia/induzido quimicamente , Epilepsia/fisiopatologia , Epinefrina/farmacologia , Feminino , Hipertensão/fisiopatologia , Ratos , Ratos Wistar , Ácido gama-Aminobutírico/farmacologia
7.
Pharmacol Res ; 43(5): 469-72, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11394939

RESUMO

Osmotic and ionic balance in the central nervous system is especially regulated by solutes and water transport across the blood-brain barrier. The aim of this study was to investigate the effect of systemic hyperosmolarity on the blood-brain barrier permeability in both sexes after experimentally induced seizures. Eight groups of rats were studied: Group I: female control; Group II: male control; Group III: hyperosmotic female; Group IV: hyperosmotic male; Group V: non-hyperosmotic female + seizure; Group VI: non-hyperosmotic male + seizure; Group VII: hyperosmotic female + seizure; Group VIII: hyperosmotic male + seizure. In female rats with pentylenetetrazol-induced seizures, the extravasation of Evans-blue was greater in the brains of hyperosmotic animals than that in normal rats (P < 0.02). However, in male rats, the extravasation of Evans-blue was similar in the brains of hyperosmotic male rats and normal rats after seizure. Our results concluded that hyperosmotic female rats were shown to have a large increase in blood-brain barrier permeability in comparison to hyperosmotic male rats after pentylenetetrazol-induced seizures.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Epilepsia/metabolismo , Solução Salina Hipertônica/toxicidade , Animais , Convulsivantes , Epilepsia/induzido quimicamente , Feminino , Masculino , Concentração Osmolar , Pentilenotetrazol , Ratos , Ratos Wistar , Caracteres Sexuais
8.
J Neurosci Res ; 62(5): 750-3, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11104514

RESUMO

To understand the increased susceptibility of the development of serious complications to hypoosmotic hyponatremia in young females, we examined the resistance of blood brain barrier (BBB) permeability to water along with the synaptosomal Na(+),K(+)ATPase activity in both sexes of rats during acute water intoxication. Four groups of rats were used: Group I and II were normal female and male rats injected with only Evans-blue. Group III and IV were water intoxicated female and male rats respectively. BBB permeability in female rats was found to be increased following acute water intoxication. In contrast, synaptosomal Na(+),K(+)ATPase activities in both water intoxicated male and female rats were found significantly lower than those in control rats. But inhibition in enzyme activity in synaptosomes from water intoxicated female rats was more pronounced than those of corresponding male rats. Our results concluded that female sex steroids may be responsible for the highly significant decrease in synaptosomal Na(+),K(+)ATPase activity and increased BBB permeability in female rats following water intoxication.


Assuntos
Barreira Hematoencefálica , ATPase Trocadora de Sódio-Potássio/metabolismo , Intoxicação por Água/metabolismo , Doença Aguda , Animais , Transporte Biológico , Feminino , Masculino , Concentração Osmolar , Permeabilidade , Ratos , Ratos Wistar , Fatores Sexuais , Intoxicação por Água/sangue
9.
Int J Neurosci ; 105(1-4): 27-35, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11069044

RESUMO

We have examined the effect of antioxidants (vitamin E, and selenium) on the blood-brain barrier permeability during adreneline-induced acute hypertension in the female rats. The rats supplemented with nontoxic doses of sodium selenite in drinking water for three months or vitamin E was given intraperitoneally before adrenaline-induced acute hypertension. Evans-blue was used as a blood-brain barrier tracer. Mean values for Evans-blue dye were found to be 0.28 +/- 0.04 microg/g tissue in control animals and 1.0 +/- 0.2 microg tissue after adrenaline-induced acute hypertension (p < .01). Rats pretreated with selenium or vitamin E also showed macroscopic leakage of Evans-blue albumin after adrenaline injection i.e., there was no significant difference in protein extravasation between untreated and treated animals (p > .5). The mean value for Evans-blue dye was found to be 1.0 +/- 0.2 microg/g tissue in acute hypertension group, 0.9 +/- 0.2 microg/g tissue in selenium pretreated animals and 1.0 +/- 0.2 micrg/g tissue vitamin E injected animals after acute hypertension. The results show that antioxidants did not influence the blood-brain barrier breakdown during adrenaline-induced acute hypertension.


Assuntos
Antioxidantes/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Selênio/farmacologia , Vitamina E/farmacologia , Animais , Corantes , Epinefrina , Azul Evans , Feminino , Hipertensão/induzido quimicamente , Hipertensão/fisiopatologia , Ratos , Ratos Wistar
10.
Int J Neurosci ; 103(1-4): 33-40, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10938561

RESUMO

The aim of the present study was to obtain information about the effects of pentylenetetrazol-induced status epilepticus (SE) and streptozotocin-induced diabetes on brain cortex Ca(2+)ATPase activity. Treatment with pentylenetetrazol (PTZ) and streptozotocin (STZ) to rats resulted in significant decrease in brain cortex Ca(2+)ATPase activity as compared with controls. However, PTZ-treated diabetic rats had a slight but non-significant decrease in enzyme activity. Treatment with PTZ caused a more pronounced effect in inhibiting enzyme activity than that of treatment with STZ. Our results concluded that reduced brain cortex Ca(2+)ATPase activity following PTZ and STZ treatments to rats, may be an initial biochemical lesion which triggers a sequence of events which may culminate in cell death.


Assuntos
ATPases Transportadoras de Cálcio/metabolismo , Córtex Cerebral/enzimologia , Diabetes Mellitus Experimental/metabolismo , Estado Epiléptico/metabolismo , Animais , Antibióticos Antineoplásicos , Córtex Cerebral/fisiopatologia , Ativação Enzimática/efeitos dos fármacos , Feminino , Antagonistas GABAérgicos , Masculino , Pentilenotetrazol , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/metabolismo , Estado Epiléptico/induzido quimicamente , Estreptozocina
11.
Int J Neurosci ; 99(1-4): 105-12, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10495209

RESUMO

The influence of the calcium channel blocker nifedipine plus bicuculline-induced seizures on the permeability of the blood-brain barrier to protein was studied in rats. Evans-blue was used as a blood-brain barrier tracer. Four groups of rats were studied. Group I: control, Group II: Nifedipine, Group III: bicuculline-induced seizure, Group IV: Nifedipine + seizure. The mean value for Evans-blue dye in the brain was found to be 0.23+/-0.03 mg/g in control animals and 0.32+/-0.06 mg/g in the group of all rats during nifedipine-induced hypotension. This difference between control and hypotensive animals was not statistically significant (p < 0.5). Mean value for Evans-blue dye in the brain was found to be 1.4+/-0.3 mg/g in bicuculline-induced seizure, and 0.73+/-40.2 mg/g in the group of nifedipine plus bicuculline-induced seizures. This difference between Group III and Group IV was found statistically significant (p < .01). The calcium channel blocker nifedipine significantly prevents the blood brain barrier disruption during bicuculline-induced seizure.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Azul Evans/farmacocinética , Nifedipino/farmacologia , Estado Epiléptico/tratamento farmacológico , Animais , Bicuculina , Pressão Sanguínea/efeitos dos fármacos , Capilares/efeitos dos fármacos , Capilares/metabolismo , Convulsivantes , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Masculino , Pinocitose/efeitos dos fármacos , Ratos , Ratos Wistar , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismo
12.
Psychiatry Res ; 82(2): 129-33, 1998 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-9754455

RESUMO

The asymmetrical breakdown of the blood-brain barrier to Evans-blue was studied in male and female rats during epileptiform seizures and in acute hypertension. The animals were divided into six groups. Group I: control female; Group II: control male; Group III: female + acute hypertension; Group IV: male + acute hypertension; Group V: female + seizure; Group VI: male + seizure. Asymmetric breakdown of the blood-brain barrier had been seen in female rats treated with pentylenetetrazol. Pentylenetetrazol-induced seizure produces less disruption of the blood-brain barrier in right cerebral hemisphere than in left cerebral hemisphere in female rats. There were no asymmetrical changes of blood-brain barrier permeability between the left and right hemispheres in acute hypertension in both sexes, and male rats treated with pentylenetetrazol.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Convulsivantes/farmacologia , Lateralidade Funcional , Hipertensão/fisiopatologia , Pentilenotetrazol/farmacologia , Convulsões/induzido quimicamente , Animais , Pressão Sanguínea/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Permeabilidade Capilar/efeitos dos fármacos , Feminino , Masculino , Ratos , Ratos Wistar , Convulsões/fisiopatologia , Caracteres Sexuais
13.
Horm Metab Res ; 30(8): 500-3, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9761379

RESUMO

The changes in the permeability of the blood-brain barrier (BBB) during bicuculline-induced seizures were investigated in ovariectomized female and orchidectomized male rats. The rats were anesthetized with diethyl ether. Evans blue, which was used as a BBB tracer, was injected into femoral vein 5 min before administering bicuculline to induce grandmal seizures. Ten groups of rats were studied: Group I: control female; Group II: control male; Group IIl: intact female + bicuculline; Group IV: intact male + bicuculline; Group V: ovariectomized female; Group VI: orchidectomized male; Group VII: ovariectomized female + bicuculline; Group VIII: orchidectomized male + bicuculline (1.2 mg/kg, i.v.); Group IX: ovariectomized female + estrogen + bicuculline; Group X: orchidectomized male + estrogen + bicuculline. Adult male and female rats were orchidectomized and ovariectomized 3 weeks before the experiments, or sham operated under general anesthesia. During bicucculline-induced seizures, the mean arterial blood pressure increased significantly in both intact and ovariectomized and orchidectomized rats. BBB lesions were present in 80 percent of intact female rats and 50 percent of ovariectomized rats after bicuculline-induced seizures. This difference between intact and ovariectomized rats was found to be significant (p < 0.01). There was no statistically significant change in the BBB permeability between intact and orchidectomized rats after convulsion. Generating seizures in both ovariectomized and orchidectomised rats, after administrating of estrogen, did not lead to any significant alteration in BBB permeability. Our results suggest that the extravasation of Evans blue albumin was most pronounced in the brain of intact female rats when compared to ovariectomized rats after bicuculline-induced seizures. After administrating estrogen, the decreased BBB permeability values of ovariectomised rats could not reach the values in intact rats.


Assuntos
Bicuculina , Barreira Hematoencefálica , Orquiectomia , Ovariectomia , Convulsões/induzido quimicamente , Convulsões/fisiopatologia , Animais , Azul Evans , Feminino , Masculino , Ratos , Ratos Wistar , Albumina Sérica/metabolismo
14.
Int J Hyperthermia ; 14(4): 395-401, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9690151

RESUMO

An animal model for reversible blood-brain barrier disruption has been developed. Retrograde infusion of hyperthermic saline solution 43 degrees C into the left external carotid artery of normothermic, Wistar rats, reversibly increases cerebrovascular permeability to Evans-blue albumin in the left cerebral hemisphere. Isotonic saline solutions at 37 degrees C for group I and 43 degrees C for group II were infused for 30-s at a constant rate of 0.12 ml/s into the left external carotid artery. Evans-blue, the barrier tracer was administered intravenously either prior to or at intervals of 5, 30, 180, 360 min after the hyperthermic saline infusion under pentobarbital anesthesia. All animals receiving hyperthermic saline perfusion had disturbed blood-brain barrier permeability. Based on visual inspection, disruption grade in the left hemispheres of six of 11 animals was grade 3+. Mean values for Evans-blue dye were found to be 0.28 +/- 0.06 mg/g of tissue in left hemisphere after normothermic saline infusion (group I), and 2.41 +/- 0.5 mg/g of tissue in the same hemisphere after hyperthermic saline infusion (group II). The difference was found to be significant between group I and group II (p < 0.01). The increase in cerebrovascular permeability was temporary, even though Evans-blue albumin extravasation remained slightly elevated 3 h after infusion and was normal 6 h after infusion.


Assuntos
Barreira Hematoencefálica/fisiologia , Hipertermia Induzida/métodos , Cloreto de Sódio/administração & dosagem , Animais , Artérias Carótidas , Azul Evans/farmacocinética , Infusões Intra-Arteriais , Masculino , Modelos Biológicos , Ratos , Ratos Wistar
15.
16.
Pharmacol Res ; 36(1): 69-72, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9368917

RESUMO

The aim of this study was to investigate the brain cortex Na(+)-K+ ATPase activity in rats made diabetic by streptozotocin and epileptic by pentylenetetrazol. Streptozotocin diabetic rats showed a significant decrease in brain cortex Na(+)-K+ ATPase activity whereas the pentylenetetrazol treatment caused no significant change in enzyme activity. On the other hand, no brain cortex Na(+)-K+ ATPase activity could be detected in all the diabetic rats treated with pentylenetetrazol. Our results concluded that reduced Na(+)-K+ ATPase activity in streptozotocin diabetic rats may contribute to the pathogenesis of metabolic complications of the central nervous system, and that the undetectable enzyme activity in diabetic convulsing rats may result from considerable damage or necrosis of brain tissue during pentylenetetrazol seizures.


Assuntos
Córtex Cerebral/enzimologia , Convulsivantes/farmacologia , Diabetes Mellitus Experimental/enzimologia , Epilepsia/enzimologia , Pentilenotetrazol/farmacologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Epilepsia/induzido quimicamente , Ratos , Ratos Wistar , Convulsões/enzimologia
17.
Neurosci Lett ; 190(3): 203-6, 1995 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-7637893

RESUMO

An animal model for reversible blood-brain barrier disruption has been developed. Retrograde infusion of hypothermic saline solution (8 +/- 1 degree C) into the left external carotid artery of normothermic, Wistar rats reversibly increases cerebrovascular permeability to Evans blue albumin in the left cerebral hemisphere. Isotonic saline solutions at 37 degrees C for Group I and at 8 +/- 1 degree C for Group II were infused for 30 s at a constant rate of 0.12 ml/s into the left external carotid artery. Evans blue, the barrier tracer, was administered intravenously either prior to or at intervals 5, 30, 180, 360 min after the hypothermic saline infusion under pentobarbital anesthesia. All animals receiving hypothermic saline perfusion had disturbed blood-brain barrier permeability. Based on visual inspection, disruption grade in the left hemispheres of 10 of 16 animals was 3+. Mean values for Evans blue dye were found to be 0.32 +/- 0.08 mg% in left the hemisphere after normothermic saline infusion (Group 1), and 2.9 +/- 0.4 mg% in the same hemisphere after hypothermic saline infusion (Group II). The difference was found to be significant between Group I and Group II (P < 0.001). The increase in cerebrovascular permeability was temporary, however, although Evans blue albumin extravasion remained slightly elevated 3 h after infusion, it was normal 6 h after infusion.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Hipotermia Induzida , Cloreto de Sódio/farmacologia , Animais , Barreira Hematoencefálica/fisiologia , Artéria Carótida Externa , Modelos Animais de Doenças , Azul Evans , Extravasamento de Materiais Terapêuticos e Diagnósticos/diagnóstico , Infusões Intra-Arteriais , Soluções Isotônicas/administração & dosagem , Soluções Isotônicas/farmacologia , Masculino , Ratos , Ratos Wistar , Cloreto de Sódio/administração & dosagem
18.
Neurosci Lett ; 188(1): 53-6, 1995 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-7783978

RESUMO

The effect of acute arterial hypertension on blood-brain barrier (BBB) permeability was studied in streptozocin-induced diabetic rats using Evans blue as a barrier tracer. Four groups of rats were studied: Group 1, normotensive normoglycemia; Group II, normotensive+diabetes mellitus; Group III, arterial hypertension+diabetes mellitus; Group IV, arterial-hypertension+normoglycemia. During adrenaline-induced acute arterial hypertension the mean arterial blood pressure increased in both non-diabetic and diabetic animals. Changes in BBB permeability were observed in 52% of the non-diabetic rats, and in 72% of the diabetic rats after adrenaline-induced acute arterial hypertension. Mean levels of Evans blue in the whole brain were found to be 0.63 +/- 0.1 mg% in non-diabetic and 0.90 +/- 0.2 mg% in diabetic rats. The difference between the non-diabetic and the diabetic rats was found to be statistically significant (P < 0.01). From these results it was suggested that the extravasation of Evans blue albumin is more pronounced in the brains of diabetic rats in comparison with non-diabetic rats after adrenaline-induced acute hypertension, which is indicative of changes in BBB permeability due to diabetes mellitus.


Assuntos
Barreira Hematoencefálica , Diabetes Mellitus Experimental/metabolismo , Hipertensão/metabolismo , Animais , Glicemia/análise , Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Epinefrina/farmacologia , Azul Evans , Hipertensão/induzido quimicamente , Masculino , Permeabilidade , Ratos , Ratos Wistar
19.
Epilepsy Res ; 19(3): 221-7, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7698098

RESUMO

The changes in the permeability of the blood-brain barrier during pentylenetetrazol (PTZ)-induced seizures were investigated in normothermic and hypothermic rats. Six groups of rats were studied: (I) normothermic control; (II) hypothermic control; (III) normothermia plus PTZ (80 mg/kg); (IV) normothermia plus PTZ (160 mg/kg); (V) hypothermia plus PTZ (80 mg/kg); (VI) hypothermia plus PTZ (160 mg/kg). The rats were anesthetized with diethyl ether. In the hypothermic animals, colonic temperature was reduced to 20 +/- 1 degree C by submerging the animals in ice water. In normothermic animals, distinct Evans-blue leakage was observed in the occipital cortex, thalamus, hypothalamus, substantia nigra, corpus striatum, and medulla oblongata in both PTZ groups. However, hypothermic animals which received a high dose of PTZ showed the most severe blood-brain barrier breakdown. Mean levels of Evans blue in the brains of low-dose (80 mg/kg) PTZ-treated animals were 8.7 +/- 2.2 micrograms/g and 5.7 +/- 1.4 micrograms/g in the normothermic and hypothermic groups, respectively. This difference was significant (P < 0.01). The levels in the high dose (160 mg/kg) PTZ-treated animals were 10.2 +/- 3.5 micrograms/g and 15.9 +/- 3.6 micrograms/g in the normothermic and hypothermic groups, respectively (P < 0.02). In conclusion, deep hypothermia prevents the blood-brain barrier disruption induced by 80 mg/kg pentylenetetrazol and aggravates the increase in permeability after 160 mg/kg pentylenetetrazol.


Assuntos
Barreira Hematoencefálica/fisiologia , Hipotermia Induzida , Convulsões/fisiopatologia , Animais , Pressão Sanguínea/fisiologia , Encéfalo/patologia , Masculino , Pentilenotetrazol , Ratos , Ratos Wistar , Convulsões/induzido quimicamente
20.
Pharmacol Res ; 28(4): 317-23, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8140031

RESUMO

The effect of pregnancy on blood-brain barrier permeability was investigated during bicuculline-induced seizure in Wistar rats, using Evans-blue as a tracer. The experiments were carried out with two methods to investigate the integrity of the blood-brain barrier, i.e. Evans-blue albumin extravasation was determined as a macroscopical finding. A quantitative estimation with a spectrophotometer using homogenized brain to release the dye was performed to evaluate the macroscopical findings in a separate group of animals. During convulsions the mean arterial blood pressure increased in both pregnant and nonpregnant rats. The extravasation of Evans-blue was more pronounced in the nonpregnant rats. Mean values for Evans-blue dye were found to be 0.29 +/- 0.07 mg% whole brain in nonpregnant control female rats and 0.30 +/- 0.09 mg% whole brain in pregnant rats. This difference was not significant (P > 0.05). Mean values for Evans-blue dye were 1.02 +/- 0.30 mg% whole brain in nonpregnant female rats, and 0.60 +/- 0.12 mg% in the pregnant rats during bicuculline-induced seizures. This difference was significant (P < 0.01). The severe protein leakage was seen in the thalamus, midcaudate, hypothalamus and mesencephalon bilaterally in the nonpregnant rats. However, in pregnant rats, Evans-blue leakage was similar to that of female rats except that the intensity of blood-brain barrier breakdown was less after convulsion.


Assuntos
Barreira Hematoencefálica , Complicações na Gravidez/metabolismo , Convulsões/metabolismo , Animais , Bicuculina , Azul Evans , Feminino , Gravidez , Ratos , Ratos Wistar
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