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1.
Neuro Endocrinol Lett ; 39(3): 209-218, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30431738

RESUMEN

OBJECTIVES: This paper presents our own rat model of the cellular brain edema, induced by water intoxication (WI). The basic principle of the model is an osmotic imbalance in the cell membrane followed by an intracellular flow of sodium and simultaneous accumulation of water leading to the subsequent increase of BBB permeability. METHODS: The usefulness of the model was tested in precisely specified conditions whose results were clearly expressed. The procedure determined both how WI induces cellular edema as well as the disturbances caused by cellular edema. RESULTS: The evidence of existing cellular edema with increased BBB permeability was proved by intracellular accumulation of intravital dye with a large molecular size; increased brain-water content was confirmed by using the dry/wet weight method and by the decrease in CT density; the elevated intracranial pressure (ICP) due to the expanding volume was determined by continuous monitoring the ICP; the structural lesions were proved by identification of the myelin disintegration; and the impaired nervous functions was demonstrated by the of open field test method. CONCLUSION: Our experimental model can help the future studies of pathophysiology of cellular brain edema and is suitable for testing neuroprotective agents.


Asunto(s)
Conducta Animal , Edema Encefálico/fisiopatología , Modelos Animales de Enfermedad , Hipertensión Intracraneal/fisiopatología , Locomoción , Ratas , Intoxicación por Agua/fisiopatología , Animales , Barrera Hematoencefálica/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Encéfalo/patología , Edema Encefálico/etiología , Edema Encefálico/metabolismo , Edema Encefálico/patología , Azul de Evans , Hipertensión Intracraneal/etiología , Hipertensión Intracraneal/metabolismo , Hipertensión Intracraneal/patología , Masculino , Vaina de Mielina/patología , Permeabilidad , Ratas Wistar , Tomografía Computarizada por Rayos X , Intoxicación por Agua/complicaciones , Intoxicación por Agua/metabolismo , Intoxicación por Agua/patología
2.
Neuro Endocrinol Lett ; 39(4): 310-314, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30531705

RESUMEN

OBJECTIVES: Effect of recombinant human erythropoietin (rhEPO) on spontaneous motor activity was tested in young rats after intraperitoneal (i.p.) administration of rhEPO, followed by induction of cellular brain edema (CE). Induced changes in the spontaneous horizontal locomotor activity was studied by open field test (OFT). METHODS: CE was induced by water intoxication (WI) using standard method of fractional hyperhydration accompanied with desmopressin administration. Using the accepted method of OFT average time spent in locomotion (s) was determined. 48 young rats at the age of 25, and 35 days were divided into three groups - controls, rats after WI (OFT followed after 44 hours), and rats administered with rhEPO prior to application WI (OFT after 48 hours). RESULTS: In 35-day-old rats rhEPO administration increased the spontaneous locomotor activity, previously decreased by cellular edema. In 25-day-old rats, rhEPO administration prior to the induced CE, decreased spontaneous locomotor activity. CONCLUSION: Presented results demonstrate the neuroprotective capacity of rhEPO, manifested by elimination of the suppressive influence of CE on the locomotion in 35-day-old rats. In 25-day-old rats the neuroprotective effect was not present. These results confirmed that the 10 day interval in the development may represent a different stage of brain maturation in the relation to the neuroprotective effect of rhEPO.


Asunto(s)
Conducta Animal/efectos de los fármacos , Edema Encefálico/fisiopatología , Eritropoyetina/farmacología , Locomoción/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Intoxicación por Agua/fisiopatología , Factores de Edad , Animales , Masculino , Ratas , Ratas Wistar , Proteínas Recombinantes/farmacología
3.
Neuro Endocrinol Lett ; 38(6): 408-414, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29298281

RESUMEN

OBJECTIVE: The aim of the study was to find how a simultaneous impairment of the CNS (cellular brain edema induced by water intoxication) and PNS (blockade of the right forelimb brachial plexus by local anesthewtic - Marcaine) affects spontaneous locomotor activity of adult rats. METHODS: Rats were divided into groups of animals without water intoxication (without WI) - A,B,C, and those that were water intoxicated (induction of brain edema - after WI) - D,E,F. Both groups were further divided into intact ones (A,D), animals with PNS lesion (Marcaine) (B,E) and sham-operated animals (C,F). Locomotor activity (LA) of the rats was tested by the open field test. RESULTS: LA of rats with both CNS and PNS impairment (WI + Marcaine) was significantly suppressed compared to the activity of control rats. Comparison of LA of rats with a single lesion - PNS impairment only (Marcaine only), CNS lesion only (WI) to those animals with both lesions (WI + Marcaine) revealed even larger decrease of LA of rats with combined lesions, which represents a model of the dual diagnosis. Also the pattern of behaviour of rats in both sham operated groups was different, which apparently depended on water intoxication. CONCLUSION: The presented results show that the LA of rats with combined lesions is significantly lower compared to the activity of rats with a single lesion in the CNS or PNS. Results also indicate that the already induced endoneurial edema prevents subsequent accumulation of water applied to the intimate vicinity of the peripheral nervous structures.


Asunto(s)
Edema Encefálico/fisiopatología , Actividad Motora/fisiología , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Intoxicación por Agua/fisiopatología , Animales , Edema Encefálico/complicaciones , Modelos Animales de Enfermedad , Masculino , Enfermedades del Sistema Nervioso Periférico/complicaciones , Ratas , Ratas Wistar , Intoxicación por Agua/complicaciones
4.
Neuro Endocrinol Lett ; 38(7): 495-501, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29369601

RESUMEN

OBJECTIVE: Locomotion, rearing and grooming represent different forms of behaviour and motor activity in rats. In this study, changes in these activities were analysed in relation to impaired function of the nervous system by single and/or concomitant lesions representing an experimental model of the dual diagnosis. METHODS: 32 rats were divided into 4 groups of 8 rats: intact rats, rats with single lesion of peripheral nervous system (PNS) - Marcaine neuropathy, rats with single CNS lesion - cellular brain edema induced by water intoxication, and the concomitant lesions (combination of CNS and PNS lesion in one rat). Water intoxication was performed in a standard way by fractionated hyperhydration. The average time spent by locomotion, rearing and grooming was registered and analyzed using an open field test. RESULTS: All activities of the rats after water intoxication became inhibited due to the generally suppressive effect of brain edema. Lesion of PNS reduced activity in locomotion only, because for rearing and grooming activities, the function of the forelimb is not dominant. Combination of lesions (dual diagnosis) reduced locomotion and rearing activity more than single lesions, and enhances the stressogenic effect, which was manifested by a long periods of grooming. CONCLUSION: Results of our study confirmed the physiological and pathophysiological differences in the movement stereotype between locomotion, rearing and grooming caused by the characteristics and algorithms of the movements, which are inborn to rats - the dominant role of the forelimbs in locomotion, the dominant exploratory activity in rearing, and the precise syntactic movement pattern in grooming.


Asunto(s)
Conducta Animal/fisiología , Edema Encefálico/fisiopatología , Aseo Animal/fisiología , Locomoción/fisiología , Actividad Motora/fisiología , Enfermedades del Sistema Nervioso Periférico/fisiopatología , Intoxicación por Agua/fisiopatología , Animales , Bupivacaína , Masculino , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Ratas , Ratas Wistar
5.
Neuro Endocrinol Lett ; 37(3): 207-212, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27618604

RESUMEN

OBJECTIVES: The aim of the study was to determine whether the functional state of neurons is affected by the duration of the induced cellular edema and by the age of animals tested. The cellular edema was induced by water intoxication and neuronal functions were tested by the standard method of electrical stimulation of neurons of the cerebral cortex. METHODS: water intoxication was induced by standard method of fractionated hyperhydration. Excitability of cortical neurons was tested by cortical stimulation with the intensity required to induce cortical afterdischarge (AD). Animals were divided into three experimental groups (B, C, D) and three control groups (AB, AC, AD). Experimental groups differed in age of water intoxication (12 or 25 days) and age of excitability testing (25 or 35 days). Changes in the duration of AD (seconds) were statistically evaluated. RESULTS: Duration of cortical afterdischarges (AD) in the control groups was at the level literature data. In all experimental groups (B, C, D), excitability of cortical neurons was markedly inhibited. AD was possible to induce only in some of the animals and its average duration was significantly shorter than in control groups. CONCLUSION: This inhibitory effect can be explained by persistent impairment of astrocyte-to-neuron communication, which plays a key role in the process of formation of structural and functional changes during cellular edema. Some of the functional manifestations of the developing edema are influenced by the age of experimental animals. At least some events of this process are not influenced by the age of experimental animals.


Asunto(s)
Neuronas/ultraestructura , Intoxicación por Agua/patología , Envejecimiento , Animales , Corteza Cerebral/citología , Corteza Cerebral/efectos de los fármacos , Edema , Estimulación Eléctrica , Electroencefalografía , Masculino , Neuronas/patología , Ratas , Ratas Wistar
6.
Prague Med Rep ; 116(2): 87-111, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26093665

RESUMEN

Adipose tissue is recognized as an active endocrine organ that produces a number of endocrine substances referred to as "adipokines" including leptin, adiponectin, adipolin, visfatin, omentin, tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), resistin, pigment epithelium-derived factor (PEDF), and progranulin (PGRN) which play an important role in the food intake regulation and significantly influence insulin sensitivity and in some cases directly affect insulin resistance in skeletal muscle, liver, and adipose tissue. The review summarizes current knowledge about adipose tissue-derived hormones and their influence on energy homeostasis regulation. The possible therapeutic potential of these adipokines in the treatment of insulin resistance, endothelial dysfunction, a pro-inflammatory response, obesity, eating disorders, progression of atherosclerosis, type 1 diabetes, and type 2 diabetes is discussed.


Asunto(s)
Adipoquinas/fisiología , Tejido Adiposo/metabolismo , Microambiente Celular/fisiología , Ingestión de Energía/fisiología , Metabolismo Energético/fisiología , Homeostasis/fisiología , Humanos , Resistencia a la Insulina/fisiología
7.
Neuro Endocrinol Lett ; 35(4): 274-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25038600

RESUMEN

OBJECTIVES: Our previous experiments with animal models revealed that water intoxication induces brain oedema and opens plasma membranes. Present study is aimed to determine whether the standard method of hyperhydration can influence cerebral microenvironment also in young rats. Neuronal functions were tested by standard electrical cortical stimulation. METHODS: Hyperhydration was induced by administration of distilled water (DW) intraperitoneally. Three groups of young rats were used: 12, 25, and 35-day-old. Cortical excitability was tested 19 to 20 hours after DW administration by electrical stimulation of the sensorimotor cortex with intensity necessary to elicit cortical afterdischarges (AD). Water content in the brain was estimated by dry/wet ratio and value of natremia by standard biochemical examination. Control animals of the same age groups were tested in the same way, only they did not receive DW. RESULTS: Brain water content in hyperhydrated animals was smaller than in controls in all studied age groups. Natremia was the same (normal) in both the hyperhydrated and control animals aged 25 days. Excitability of cortical neurons in young hyperhydrated animals was significantly inhibited in comparison to the same age groups of controls. CONCLUSION: Hyperhydration induced in young rats (12, 25, 35-day-old) had different effects than in adults. Absence of hyponatremia, lower water content in the brain and significant inhibition of cortical excitability can be explained on the basis of ontogenetically dependent aquaporine expression (AQP 4) and different activity of ionic membrane transporters.


Asunto(s)
Agua Corporal/metabolismo , Encéfalo/fisiopatología , Intoxicación por Agua/fisiopatología , Animales , Encéfalo/metabolismo , Corteza Cerebral/fisiopatología , Modelos Animales de Enfermedad , Fenómenos Electrofisiológicos/fisiología , Masculino , Neuronas/fisiología , Ratas , Ratas Wistar , Intoxicación por Agua/inducido químicamente
8.
Prague Med Rep ; 115(1-2): 5-15, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24874930

RESUMEN

We tested the influence of erythropoietin (EPO), a basic cytokine in erythropoiesis regulation, on the process of motor function and cognition after focal brain ischemia induced by a local application of endothelin. Endothelin-1 (ET-1) induced short lasting strong vasoconstriction, with described impact on the structure and on the function of neuronal cells. Neurological description of motor function and Morris water maze test (the swimming test is one of most widely used methods for studying cognitive functions in rodents) were used to study the process of learning and memory in three-month-old male albino Wistar rats (n=52). Both tests were performed one week before, and three weeks after ischemia induction (endothelin application on the cortex in the area of a. cerebri media dx.). Experimental group received i.p. injection of EPO (5,000 IU/kg body weight, 10 min before endothelin application). Control group of animals received one i.p. injection of saline at the dose of 1 ml/kg body weight at the same time. Only sham surgery was performed in the third group of animals. Rats with EPO pretreatment before the experimental lesion exhibited significantly better motor and cognitive function then those with saline injection. No significant changes in the motor and cognitive function were found in the third group of rats (sham operated controls).


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/fisiopatología , Cognición/efectos de los fármacos , Eritropoyetina/farmacología , Actividad Motora/efectos de los fármacos , Animales , Isquemia Encefálica/inducido químicamente , Endotelina-1 , Eritropoyetina/administración & dosificación , Masculino , Ratas , Ratas Wistar
9.
Neuro Endocrinol Lett ; 33(5): 530-5, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23090272

RESUMEN

OBJECTIVES: The effects of ascorbic acid and α-tocopherol pre-treatment on hypoxia induced changes in brain cortex excitability were tested in immature rats exposed chronically to simulated altitude of 7 000 m. METHODS: Rat pups were kept together with their mothers for 8 hours a day in hypobaric chamber since the day of the birth till the postnatal day 11 or 17. Each day immediately before placing to hypobaric chamber pups were pretreated intraperitoneally either with ascorbic acid (100 mg/kg) or α-tocopherol (1 500 mg/kg). Cortical afterdischarges were elicited by repeated stimulation of the right sensorimotor cortex. The duration of evoked cortical afterdischarges was analyzed. RESULTS: Duration of cortical afterdischarges progressively declines with age. Hypoxia prolonged the duration of afterdischarges in 12-, 18- and 25-day-old animals. Pretratment with ascorbic acid or α-tocopherol shorted afterdischarges duration in youngest experimental group when compared with animals exposed to hypoxia only. CONCLUSION: Hypoxia significantly affects the brain cortex excitability by prolonging afterdischarges duration. This effect differs with age. Antioxidant pre-treatment brought about shorter duration of cortical afterdischarges only in the youngest experimental group. The antioxidant effect is therefore age dependent.


Asunto(s)
Ácido Ascórbico/farmacología , Corteza Cerebral/efectos de los fármacos , Potenciales Evocados/efectos de los fármacos , Hipoxia Encefálica/tratamiento farmacológico , alfa-Tocoferol/farmacología , Factores de Edad , Animales , Animales Recién Nacidos , Antioxidantes/farmacología , Corteza Cerebral/crecimiento & desarrollo , Corteza Cerebral/metabolismo , Epilepsia/tratamiento farmacológico , Epilepsia/metabolismo , Epilepsia/fisiopatología , Femenino , Hipoxia Encefálica/metabolismo , Hipoxia Encefálica/fisiopatología , Masculino , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Embarazo , Ratas
10.
Gen Physiol Biophys ; 31(2): 173-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22781820

RESUMEN

The aim of present study was to examine the impact of prenatal ethanol exposure on seizure susceptibility of the offspring. Pregnant Wistar rats were compelled to drink either 10% or 20% ethanol solution, as the only drinking fluid since conception up to the weaning of their offspring at the age of 28 days. Pregnant and nursing rats of the control group drank water. Electrophysiological experiments (repeated electrical stimulation and analysis of cortical afterdischarges duration) were than performed on their immature offspring. Rat pups were tested on postnatal day 18, 25, and 35. Shortening of afterdischarges duration was observed in 18-day-old animals (mothers drank 20% ethanol) when compared with age matched controls and failure of post-ictal depression phenomenon was found in 25- and 35-day-old animals. Our findings signalize that ethanol exposure during pregnancy influences seizure susceptibility by acting on excitatory/inhibitory brain systems and this effect is dose- and age-dependent.


Asunto(s)
Envejecimiento/efectos de los fármacos , Encéfalo/fisiopatología , Etanol/efectos adversos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Convulsiones/inducido químicamente , Convulsiones/fisiopatología , Animales , Encéfalo/efectos de los fármacos , Susceptibilidad a Enfermedades/inducido químicamente , Susceptibilidad a Enfermedades/fisiopatología , Relación Dosis-Respuesta a Droga , Etanol/administración & dosificación , Femenino , Masculino , Embarazo , Ratas , Ratas Wistar
11.
Gen Physiol Biophys ; 30(4): 350-5, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22131316

RESUMEN

Nicotine has been repeatedly reported as substance possessing neuroprotective properties. This study focused on the possible beneficial effects of nicotine against the high-altitude hypoxia (9000 m for one hour). 15 min prior to hypoxia exposition rats (12- and 35-day-old) were treated with nicotine. Next day electrodes have been implanted and the effects of nicotine and hypoxia (or both factors) on duration of afterdischarges (ADs) were tested. Administration of nicotine declined the hypoxia-induced mortality in 35-day-old animals. Nicotine pretreatment had no effect on ADs duration in 12-day-old pups, therefore brought about suppression of ADs in 35-day-old animals. Taken together, our data show that nicotine exhibits an anticonvulsant effect that is age-dependent. The mechanisms of nicotine neuroprotective properties include probably the influence of calcium homeostasis, increase synthesis of variety of growth factors, inhibition of the caspase cascades and antioxidant capability of nicotine.


Asunto(s)
Epilepsia/tratamiento farmacológico , Hipoxia/mortalidad , Nicotina/farmacología , Altitud , Animales , Encéfalo/efectos de los fármacos , Electrocardiografía/métodos , Electrodos , Electrofisiología/métodos , Hipoxia/tratamiento farmacológico , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Masculino , Modelos Estadísticos , Fármacos Neuroprotectores/farmacología , Ratas , Ratas Wistar , Factores de Tiempo
12.
Physiol Res ; 70(S3): S289-S300, 2021 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-35099248

RESUMEN

Brain edema - a frequently fatal pathological state in which brain volume increases resulting in intracranial pressure elevation - can result from almost any insult to the brain, including traumatic brain injury. For many years, the objective of experimental studies was to find a method to prevent the development of brain edema at the onset. From this perspective, the use of methylprednisolone (MP) appears promising. High molecular MP (MW>50 kDa) can be incorporated into the brain - in the conditions of the experimental model - either by osmotic blood-brain barrier disruption (BBBd) or during the induction of cellular edema by water intoxication (WI) - a condition that increases the BBB permeability. The time window for administration of the MP should be at the earliest stages of edema. The neuroprotective effect of MP on the permeability of cytoplasmatic membranes of neuronal populations was proved. MP was administrated in three alternative ways: intraperitoneally during the induction of cytotoxic edema or immediately after finishing cytotoxic edema induction in a dose of 100 mg/kg b.w.; into the internal carotid artery within 2 h after finishing cytotoxic edema induction in a dose of 50 mg/kg b.w.; into internal carotid artery 10 min after edema induction by BBBd in a dose of 50 mg/kg b.w.


Asunto(s)
Edema Encefálico/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Glucocorticoides/farmacología , Metilprednisolona/farmacología , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Encéfalo/metabolismo , Encéfalo/patología , Edema Encefálico/metabolismo , Edema Encefálico/patología , Permeabilidad Capilar/efectos de los fármacos , Modelos Animales de Enfermedad , Masculino , Neuronas/metabolismo , Neuronas/patología , Ratas , Ratas Wistar
13.
Neuro Endocrinol Lett ; 31(6): 792-5, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21196917

RESUMEN

OBJECTIVES: Nicotine is a widely used drug of abuse exerting number of effects on the central nervous system. The study was aimed at the effects of nicotine in various doses on the excitability of cerebral cortex and - by using the methods of histochemistry - to identify possible signs of neuronal degeneration after nicotine administration. METHODS: Cortical afterdischarges were elicited by repeated stimulation of the right sensorimotor cortex. The duration of evoked ADs was monitored in animals treated with nicotine (0.75 or 1.0mg/kg) and in animals treated with saline. Methods of histochemistry (Fluoro-Jade B and bis-benzimide) were used to detect possible neuronal degeneration in hippocampus or in cerebral cortex. RESULTS: No Fluoro-Jade B positive cells were found in hippocampi of control animals, or animals treated with nicotine. ADs length was significantly influenced by administration of nicotine. CONCLUSION: Nicotine in 0.75 or 1.0 mg/kg dose leads to the decrease in ADs duration, influences the seizure susceptibility, and doesn't cause any detectable neuronal damage.


Asunto(s)
Corteza Cerebral/patología , Potenciales Evocados , Hipocampo/patología , Degeneración Nerviosa/patología , Neuronas/patología , Nicotina/efectos adversos , Convulsiones/fisiopatología , Animales , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiopatología , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Relación Dosis-Respuesta a Droga , Electrodos Implantados , Electrofisiología , Hipocampo/efectos de los fármacos , Inyecciones Intraperitoneales , Corteza Motora/patología , Degeneración Nerviosa/tratamiento farmacológico , Nicotina/administración & dosificación , Agonistas Nicotínicos/efectos adversos , Distribución Aleatoria , Ratas , Ratas Wistar , Convulsiones/tratamiento farmacológico , Convulsiones/patología
14.
Gen Physiol Biophys ; 29(1): 67-71, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20371882

RESUMEN

The aim of our study was to test the hypothesis, if melatonin pre-treatment (in dose of 100 mg/kg) can influence the changes of brain function after short-term hypoxia exposition (simulated altitude 9000 m) in young immature rats. Experiments were performed on freely moving 12-, 25- and 35-day-old male Wistar rats. One hour prior to hypoxia exposition, animals were pre-treated with melatonin and 24 hours after hypoxia cortical afterdischarges (ADs) were elicited by repeated stimulation of the right sensorimotor cortex. The duration of evoked ADs and shape of evoked graphoelements was monitored. Short-term exposure to hypoxic conditions resulted in significantly shorter ADs duration in 12-day-old rats after stimulations (except the 2nd one stimulation) compared to control group. Administration of melatonin prolonged the duration of ADs after all stimulations except the 1st one. Analysis of the duration ADs revealed no significant changes, either after the exposition to hypobaric hypoxia or after melatonin administration in 25- and 35-day-old animals. Effects and mechanisms of melatonin action on the brain seizure susceptibility and the possible beneficial role of that treatment in hypoxic brain damage are discussed.


Asunto(s)
Potenciales de Acción/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Electrocardiografía/efectos de los fármacos , Hipoxia Encefálica/fisiopatología , Melatonina/administración & dosificación , Red Nerviosa/fisiopatología , Animales , Masculino , Red Nerviosa/efectos de los fármacos , Ratas , Ratas Wistar
15.
Neuro Endocrinol Lett ; 41(7-8): 392-400, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33754596

RESUMEN

OBJECTIVES: Changes in the hippocampus induced by water intoxication were studied using fluorescence microscopy (FM) and magnetic resonance imaging (MRI). METHODS: In three animals (rats), intracellular/extracellular distribution of Evans blue (EB) in cerebral cortex and hippocampus of both hemispheres was revealed by injection of EB into the internal carotid artery (ICA) in hyperhydrated rats (water intoxication, WI). A total of 8 experimental rats were used for the MRI study. The animals were scanned before WI, then the experimental brain edema was induced by WI and MR scanning was performed at day 1 and day 8 after WI. Besides standard T2-weighted imaging an apparent diffusion coefficient (ADC) and transverse relaxation time (T2) were evaluated. RESULTS: Hyperhydration brought about the largest intracellular deposits of EB in CA3 hippocampal region, followed by the cerebral cortex and CA1 hippocampal region with the lowest amount of intracellular EB in the dentate gyrus. A higher apparent diffusion coefficient (corresponding to a vasogenic edema) was found the first day after hyperhydration in the cortex and in the CA1 and CA3 regions with no changes in dentate gyrus. CONCLUSION: Both FM and MRI confirmed a selectively higher vulnerability to hyperhydration and hyponatremia (achieved by water intoxication) of the hippocampal cells compared to dentate gyrus cells.


Asunto(s)
Edema Encefálico , Hipocampo , Animales , Encéfalo , Edema Encefálico/diagnóstico por imagen , Azul de Evans , Hipocampo/diagnóstico por imagen , Imagen por Resonancia Magnética , Microscopía Fluorescente , Ratas , Intoxicación por Agua
16.
Neuro Endocrinol Lett ; 40(7-8): 319-324, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32304368

RESUMEN

OBJECTIVES: Accurate values of the intracranial pressure (ICP) and mean arterial pressure (MAP) are the prerequisite for calculating cerebral perfusion pressure (CPP). Increased ICP values decrease CPP. The origin of ICP increase in the clinical cases after brain ischemia and diffuse brain injury is the cellular brain edema (CE). Short-term monitoring of ICP and MAP is possible only in the unconscious patients, in experiments with rats it used to be possible only in general anesthesia. Long-term monitoring of ICP or MAP in the clinical practice is not possible. We therefore introduce an experimental model with telemetric monitoring. METHODS: ICP (subdurally) and MAP (intracarotically) were monitored in freely moving rats for 72 hours by DSI™ (Data Sciences International) telemetry system. The control group consisted of 8 rats, the experimental group had 8 animals with CE-induced by water intoxication. RESULTS: The mean MAP, ICP and CPP values were significantly higher in the experimental group. Average values of MAP were 19.9 mmHg (18%), ICP 5.3 mmHg (55%), CPP 14.5 mmHg (15% higher). CONCLUSION: The results of the pilot study verified possibilities of long-term telemetric monitoring of the mean arterial and intracranial pressures for the determination of current cerebral perfusion pressure in freely moving rats under physiological conditions and with increased intracranial pressure due to the induced cerebral edema. Detailed analysis of the course of the curves in the experimental group revealed episodes of short-term CPP reduction below the optimum value of 70 mmHg. Interpretation of these episodes requires simultaneous monitoring of rat behavior.


Asunto(s)
Presión Arterial , Edema Encefálico/fisiopatología , Presión Intracraneal , Monitoreo Ambulatorio/métodos , Telemetría/métodos , Animales , Circulación Cerebrovascular , Monitoreo Ambulatorio/instrumentación , Proyectos Piloto , Ratas , Tecnología de Sensores Remotos/instrumentación , Tecnología de Sensores Remotos/métodos , Telemetría/instrumentación
17.
Neuro Endocrinol Lett ; 40(6): 249-256, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32200583

RESUMEN

OBJECTIVES: A novel method of long-term telemetric monitoring of mean arterial pressure (MAP) and intracranial pressure (ICP) for the determination of current cerebral perfusion pressure (CPP) and the time course of ICP in freely moving rats under physiological conditions and with increased ICP due to the induced cerebral edema were studied. METHODS: The brain edema, that caused volume enlargement and ICP elevation was achieved in entirely experimental conditions without any parallel pathological process. Vasogenic/extracellular edema was induced by osmotic blood-brain barrier disruption (BBBd) and for induction of cytotoxic/intracellular edema the water intoxication model (WI) was used. RESULTS: The results showed significantly elevated values of ICP both in conditions of osmotic blood-brain barrier disruption (BBBd model) and cytotoxic/intracellular edema (WI model) compared to intact rats. The average values of ICP were significantly higher in WI model compared to osmotic BBBd model. Distinct pattern of elevated ICP, related to the selected way of experimental brain edema induction, was found. In the experimental model of osmotic BBB disruption, the elevation of ICP started earlier but was of very short duration. In WI model the elevation of ICP was present during the whole period of monitoring. CONCLUSION: Our results indicate that purely experimental models of brain edema (WI, BBBd) without any parallel pathological process can compromise the basic brain homeostatic activity.


Asunto(s)
Barrera Hematoencefálica/fisiopatología , Edema Encefálico/etiología , Edema Encefálico/fisiopatología , Hipertensión Intracraneal/complicaciones , Intoxicación por Agua/complicaciones , Animales , Encéfalo/fisiopatología , Edema Encefálico/diagnóstico , Circulación Cerebrovascular/fisiología , Hipertensión Intracraneal/diagnóstico , Hipertensión Intracraneal/fisiopatología , Presión Intracraneal/fisiología , Masculino , Monitoreo Fisiológico/métodos , Ratas , Ratas Wistar , Telemetría , Intoxicación por Agua/diagnóstico , Intoxicación por Agua/fisiopatología
18.
Eur J Obstet Gynecol Reprod Biol ; 103(1): 72-4, 2002 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-12039469

RESUMEN

OBJECTIVE: To evaluate a new system for the ultrasound evaluation of urethral mobility. STUDY DESIGN: We studied the structure of interpubic disc and found landmarks that can be used to align different images and set up an universal system of coordinates. The method for capturing and post-processing of the introital ultrasound examination is described. The urethra in its entire course is evaluated. Ten patients were examined and some important points at the interpubic disc and the urethra were traced to assess the reproducibility of the method. RESULTS: The mean intra-observer difference for x and y coordinates were 1.88 mm (S.D. 1.53) and 2.00 mm (S.D. 1.54), respectively. The inter-observer difference was 2.30 mm (S.D. 1.64) and 2.50 mm (S.D. 1.79), respectively for x and y coordinates. CONCLUSION: The method shows good inter- and intra-observer correlation and presents data that can be further used for biomechanical analysis.


Asunto(s)
Ultrasonografía/métodos , Uretra/diagnóstico por imagen , Incontinencia Urinaria/diagnóstico por imagen , Fenómenos Biomecánicos , Femenino , Humanos , Imagen por Resonancia Magnética , Variaciones Dependientes del Observador , Hueso Púbico , Reproducibilidad de los Resultados , Uretra/patología , Uretra/fisiopatología , Incontinencia Urinaria/patología , Incontinencia Urinaria/fisiopatología
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