Serotonin induces or inhibits neuritic regeneration of leech CNS neurons depending on neuronal identity

Recovery of motor function after central nervous system (CNS) injury is dependent on the regeneration capacity of the nervous system, which is a multifactorial process influenced, among other things, by the role of neuromodulators such as serotonin. The neurotransmitter serotonin can promote neuronal regeneration but there are also reports of it causing restriction, so it is important to clarify these divergent findings in order to understand the direct scope and side effects of potential pharmacological treatments. We evaluated the effect of serotonin on the extent of neuritic outgrowth and morphology of three different neuronal types in the leech Haementeria officinalis during their regeneration in vitro: Retzius interneurons (Rz), annulus erector (AE) motoneurons, and anterolateral number 1 (AL1) CNS neurons. Neurons were isolated and cultured in L15 medium, with or without serotonin. Growth parameters were registered and quantified, and observed differences were analyzed. The addition of serotonin was found to induce AL1 neurons to increase their average growth dramatically by 8.3-fold (P=0.02; n=5), and to have no clear effect on AE motoneurons (P=0.44; n=5). For Rz interneurons, which normally do not regenerate their neurites, the addition of concanavaline-A causes substantial growth, which serotonin was found to inhibit on average by 98% (P=0.02; n=5). The number of primary neurites and their branches were also affected. These results reveal that depending on the neuronal type, serotonin can promote, inhibit, or have no effect on neuronal regeneration. This suggests that after CNS injury, non-specific pharmacological treatments affecting serotonin may have different effects on different neuronal populations.

Idosos residentes em uma instituição de longa permanência: adaptação à luz de Callista Roy / Elderly residents in homes for the aged: adjustment in the light of Callista Roy / Residentes mayores en un hogares para ancianos: adaptación a la luz de Callista Roy

Objetivou-se avaliar o processo de adaptação de idosos que buscam, voluntariamente, residir em Instituição de Longa Permanência para Idosos (ILPI), na cidade de Fortaleza-CE, com base no modelo teórico de Roy. Pesquisa descritiva, realizada em uma IPLI com treze idosos residentes. A coleta de dados foi por meio de entrevista, nos meses de outubro e dezembro de 2011. Os dados foram tratados pela análise de conteúdo temática. Emergiram as seguintes temáticas: Eu Físico, subdividido em sensação corporal e imagem corporal; e Eu Pessoal, subdividido em auto coerência, auto ideal e ser moral-ético-espiritual. Assim, a opção de morar em ILPI não mudou efetivamente a vida dos idosos. Estes conseguiram adaptação ao local e convivem bem com os estímulos internos e externos.

This study aimed to evaluate the adaptation of elderly individuals voluntarily reside in Institution for the Aged (LTCF) in the city of Fortaleza-CE, based on the theoretical model of Roy. Descriptive study, in a IPLI involving thirteen elderly residents. Data collect was through interviews in the months of October and December 2011 and organized by thematic content analysis. The following themes has emerged: I Physical subdivided into body sensation and body image; Staff and I, subdivided into self-consistency and auto ideal be moral-ethical-spiritual. Thus, the option to live in ILPI not effectively changed the lives of elderly people. They managed to adapt to the local and coexist well with internal and external stimuli.

Este estudio tuvo como objetivo evaluar la adaptación de las personas mayores que residen voluntariamente en la Institución para la tercera edad (LTCF) en la ciudad de Fortaleza-CE, basado en el modelo teórico de Roy. Estudio descriptivo, en un IPLI con trece ancianos residentes. Los datos fueran recogidos a través de entrevistas en los meses de octubre y diciembre de 2011 y organizados mediante análisis de contenido temático. Emergieron los siguientes temas: subdivide I Física en la imagen corporal y sensación de cuerpo; El personal y yo, subdividen en auto-consistencia y auto ideal ser moral-ético-espiritual. Por lo tanto, la opción de vivir en ILPI no cambió de manera efectiva la vida de los ancianos. Se las arreglaron para adaptarse a lo local y convivir bien con los estímulos internos y externos.

Muscular performance characterization in athletes: a new perspective on isokinetic variables

Background: Isokinetic dynamometry allows the measurement of several variables related to muscular performance, many of which are seldom used, while others are redundantly applied to the characterization of muscle function. Objectives: The present study aimed to establish the particular features of muscle function that are captured by the variables currently included in isokinetic assessment and to determine which variables best represent these features in order to achieve a more objective interpretation of muscular performance. Method: This study included 235 male athletes. They performed isokinetic tests of concentric knee flexion and extension of the dominant leg at a velocity of 60º/s. An exploratory factor analysis was performed. Results: The findings demonstrated that isokinetic variables can characterize more than muscle torque production and pointed to the presence of 5 factors that enabled the characterization of muscular performance according to 5 different domains or constructs. Conclusions: The constructs can be described by torque generation capacity; variation of the torque generation capacity along repetitions; movement deceleration capacity; mechanical/physiological factors of torque generation; and acceleration capacity (torque development). Fewer than eight out of sixteen variables are enough to characterize these five constructs. Our results suggest that these variables and these 5 domains may lead to a more systematic and optimized interpretation of isokinetic assessments. .

Effect of alcoholic extract of Nigella sativa seed on alpha motor neurons density of spinal cord following sciatic nerve compression in rats

Compression or sciatic axotomy induces neuronal death in spinal cord alpha motor neuron. This study was carried out to determine the effect of Nigella sativa seed alcoholic extract on spinal motor neuron density in anterior horn after sciatic nerve compression in rat. In this experimental study 24 wistar rats were divided into four groups A: control, B: compression, C: compression+treatment with 75 mg/kg alcoholic extract, D: compression+treatment with 50 mg/kg alcoholic extract. In control group muscle was exposed without any injury to sciatic nerve. In compression and treatment group, the right leg sciatic nerve compressed for 60 sec. After four weeks of post operation, L2-L4 and S1, S2 and S3 segments of spinal cord were sampled, processed, serially sectioned and stained with toluidine blue. The number of alpha motor neurons was counted using dissector method. Neuronal density in compression group [650 +/- 32] significantly decreased in comparison with control group [1803 +/- 24]. Neuronal density in C treated group [1581 +/- 47] and D treated group [1543 +/- 49] significantly increased compare to compression group [P<0.001]. Alcoholic extract of Nigella sativa seed increased the density of alpha motor neurons in spinal cord after sciatic nerve compression in rats

effects of cyclosporin-A on functional outcome and axonal regrowth following spinal cord injury in adult rats

It has been shown that the immunophilin ligands have the special advantage in spinal cord repair. In this study, the effects of cyclosporine A [CsA] on functional recovery and histological outcome were evaluated following spinal cord injury in rats. After spinal cord hemisection in thirty six adult female Sprague-Dawley rats [200- 250 g], treatment groups received CsA [2.5 mg/kg i.p.] at 15min and 24h after lesion [CsA 15min group and CsA 24h group] daily, for 8 weeks. Control and sham groups received normal saline and in sham operated animals the spinal cord was exposed in the same manner as treatment groups, but was not hemisected. Hindlimb motor function was assessed in 1, 3, 5 and 7 weeks after lesion, using locomotive rating scale developed by Basso, Bresnahan and Beattie [BBB]. Motor neurons were counted within the lamina IX of ventral horn and lesion size was measured in 5 mm of spinal lumbar segment with the epicenter of the lesion site. The mean number of motor neurons and the mean BBB scale in 3, 5 and 7 weeks in CsA 15min groups significantly increased compared to the control group. Although, the lesion size reduced in rats with CsA treatment compared to the control group, no significant difference was observed. Thus, it can be concluded that CsA can improve locomotor function and histological outcome in the partial spinal cord injury

[Effect of aquatic extract of cannabis sativa leaves on degeneration of alpha motoneurons in spinal cord after sciatic nerve compression in rats]

Neurons are injured under physical, chemical and pathological conditions. The effects of injuries in peripheral nervous system returns as retrograde to the cell body of neurons in central nervous system and causes brain and spinal degeneration. This study was done to evaluate the effect of aquatic extract of Cannabis sativa leaves on degeneration of alpha motoneurons in spinal cord after sciatic nerve compression in Rats. This experimental study was carried out on thirty two male Wistar rats, weighing 300-350 grams. Animals were divided into four groups each consisting eight members; A: control, B: compression, C: compression +treatment with 25 mg/kg aquatic extract, D: compression +treatment with 50 mg/kg aquatic extract. In order to induce compression in B, C and D, after cutting the right thigh muscle, Sciatic nerve of thigh was exposed to compression for 60 seconds using locker pincers. The first extract injection was done intraperitoneally immediately after compression and the second intera peritoneal injection was done 7 days later. 28 days after compression, the Lumbar spinal cord were dissected, fixed and stained with toluidine blue. The density of alpha motoneurons was measured using dissector and stereological methods. Data was analyzed with using Minitab-13 software, ANOVA and Tukey tests. Neuronal density was 611.5 +/- 34.2 and 1633.4 +/- 30.7 in compression and control groups respectively [P<0.001]. There was a meaningful statistical increase in neuronal density of group C [1278.6 +/- 28.1] in comparing compression group [P<0.001]. The neuronal density in group [D] [1549.8 +/- 87.7], significantly increased in comparison with group [B] [P<0.001]. This study showed that aquatic extract of Cannabis sativa leaves increases the density of alpha motoneurons in spinal cord after sciatic nerve compression in Rats. The increase in neuronal density is relevant to the amount of extract used

The immunomodulator glatiramer acetate influences spinal motoneuron plasticity during the course of multiple sclerosis in an animal model

The immunomodulador glatiramer acetate (GA) has been shown to significantly reduce the severity of symptoms during the course of multiple sclerosis and in its animal model - experimental autoimmune encephalomyelitis (EAE). Since GA may influence the response of non-neuronal cells in the spinal cord, it is possible that, to some extent, this drug affects the synaptic changes induced during the exacerbation of EAE. In the present study, we investigated whether GA has a positive influence on the loss of inputs to the motoneurons during the course of EAE in rats. Lewis rats were subjected to EAE associated with GA or placebo treatment. The animals were sacrificed after 15 days of treatment and the spinal cords processed for immunohistochemical analysis and transmission electron microscopy. A correlation between the synaptic changes and glial activation was obtained by performing labeling of synaptophysin and glial fibrillary acidic protein using immunohistochemical analysis. Ultrastructural analysis of the terminals apposed to alpha motoneurons was also performed by electron transmission microscopy. Interestingly, although the GA treatment preserved synaptophysin labeling, it did not significantly reduce the glial reaction, indicating that inflammatory activity was still present. Also, ultrastructural analysis showed that GA treatment significantly prevented retraction of both F and S type terminals compared to placebo. The present results indicate that the immunomodulator GA has an influence on the stability of nerve terminals in the spinal cord, which in turn may contribute to its neuroprotective effects during the course of multiple sclerosis.

Intravenous dexmedetomidine prolongs bupivacaine spinal analgesia

The prolongation of spinal anesthesia by using clonidine through the oral, intravenous and spinal route has been known. The new ?2 agonist, dexmedetomidine has been proved to prolong the spinal anesthesia through the intrathecal route. We hypothesized that dexmedetomidine when administered intravenously following spinal block, also prolongs spinal analgesia. 48 patients were randomly allocated into two equal groups following receiving spinal isobaric bupivacaine 12.5 mg. Patients in group D received intravenously a loading dose of 1 microg/kg dexmedetomidine over 10 min and a maintenance dose of 0.5 microg/kg/hr. Patients in group C [the control group] received normal saline. The regression times to reach S1 sensory level and Bromage 0 motor scale, hemodynamic changes and the level of sedation were recorded. The duration of sensory block was longer in intravenous dexmedetomidine group compared with control group [261.5 +/- 34.8 min versus 165.2 +/- 31.5 min, P < 0.05]. The duration of motor block was longer in dexmedetomidine group than control group [199 +/- 42.8 min versus 138.4 +/- 31.3 min, P < 0.05]. Intravenous dexmedetomidine administration prolonged the sensory and motor blocks of bupivacaine spinal analgesia with good sedation effect and hemodynamic stability

Labor analgesia with ropivacaine added to clonidine: a randomized clinical trial / Analgesia de parto com ropivacaína associada à clonidina: pesquisa clínica randomizada

CONTEXT AND OBJECTIVE: Previous studies have led to speculation that the association between ropivacaine and clonidine might be more effective than ropivacaine alone. We examined the maternal-fetal effects of two pharmacological approaches: a low dose of ropivacaine or a lower dose of ropivacaine plus clonidine for epidural analgesia during labor. DESIGN AND SETTING: Prospective study at Department of Anesthesiology, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista. METHODS: Thirty-two pregnant women in American Society of Anesthesiologists physical status I and II randomly underwent epidural analgesia using 15 ml of ropivacaine 0.125 percent (R group) or 15 ml of ropivacaine 0.0625 percent plus 75 µg clonidine (RC group). Pain intensity, sensory block level, latency time, motor block intensity, duration of labor analgesia and duration of epidural analgesia were evaluated. The newborns were evaluated using Apgar scores and the Amiel-Tison method (neurological and adaptive capacity score). RESULTS: There were no statistically significant differences between the groups regarding pain score, sensory block level, duration of epidural analgesia or Apgar score. The latency time, duration of labor analgesia and motor block were R group < RC group. The half-hour and two-hour neurological and adaptive capacity scores were higher in the R group. All of the R group newborns and 75 percent of the RC group newborns were found to be neurologically healthy at the 24-hour examination. RESULTS: There were no statistically significant differences between the groups regarding pain score, sensory block level, duration of epidural analgesia or Apgar score. The latency time, duration of labor analgesia and motor block were R group < RC group. The half-hour and two-hour neurological and adaptive capacity scores were higher in the R group. All of the R group newborns and 75 percent of the RC group newborns were found to be neurologically healthy...

CONTEXTO E OBJETIVO: A associação entre ropivacaína e clonidina agiria menos que a ropivacaína isolada na mãe e no feto? Foram pesquisados os efeitos materno-fetais de duas técnicas farmacológicas: pequena dose de ropivacaína ou dose menor de ropivacaína mais clonidina na analgesia peridural para parto. TIPO DE ESTUDO E LOCAL: Estudo prospectivo, Departamento de Anestesiologia, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista. MÉTODOS: Trinta e duas parturientes, estado físico de acordo com a American Society of Anesthesiologists I e II, foram aleatoriamente submetidas à analgesia peridural com 15 ml de ropivacaína 0,125 por cento (grupo R) ou 15 ml de ropivacaína 0,0625 por cento mais clonidina, 75 µg (grupo RC). Foram avaliados: intensidade da dor, nível do bloqueio sensitivo, latência, intensidade do bloqueio motor, duração da analgesia de parto e da analgesia peridural. Os neonatos foram avaliados pelo Apgar e método de Amiel-Tison (capacidade neurológica e adaptativa). RESULTADOS: Não houve diferenças significativas entre grupos para dor, nível de bloqueio sensitivo, duração da analgesia peridural e Apgar. Para latência, duração da analgesia de parto e bloqueio motor, grupo R < grupo RC. O escore da capacidade neurológica e adaptativa de meia e duas horas foi maior para o grupo R. Cem por cento dos neonatos do grupo R e 75 por cento dos do grupo RC estavam neurologicamente saudáveis ao exame de 24 horas. CONCLUSÃO: Pequena dose de ropivacaína e dose menor mais clonidina aliviaram a dor materna durante o parto. Neonatos de mães que receberam apenas ropivacaína mostraram melhores escores da capacidade neurológica e adaptativa.

Anatomic Motor Point Localization of the Biceps Brachii and Brachialis Muscles

Injection of the neurolytic agents into motor points of the biceps brachii or brachialis muscles is an effective treatment of spasticity of the elbow flexors in many stroke survivors. Accurate localization of the motor points of each muscle is necessary for enhancing the efficacy of motor point blocks. To identify the precise locations of the motor points (terminal nerve endings) of the biceps brachii and brachialis muscles in relation to anatomic surface landmarks for motor point blocks, we dissected 23 limbs from 12 cadavers. A reference line was defined as a line connecting the coracoid process with the lateral epicondyle of the humerus. The location of the motor points of the biceps brachii and brachialis muscles was identified in reference to the reference line. The motor point of the biceps brachii muscle was found to be approximately half of the reference line. In the brachialis muscle, the location of the motor point was 70% of the reference line from the coracoid process and 2 cm medial to the line. The results are expected to facilitate effective localization of the motor point block of these muscles in selective motor nerve block.

Oral zinc therapy in diabetic neuropathy.

The present double blind randomized study was conducted on 50 subjects; 20 age and sex matched healthy controls (Group--I); 15 patients of diabetes mellitus with neuropathy who received placebo for 6 weeks (Group--IIA); and 15 patients of diabetes mellitus with neuropathy who were given supplemental zinc sulphate (660 mg) for 6 weeks (Group--IIB). Serum zinc level, fasting blood sugar (FBS) and post prandial blood sugar (PPBS) levels and motor nerve conduction velocity (MNCV) were estimated on day 0 and after 6 weeks in all subjects. Serum zinc levels were significantly low (p < 0.001) in group IIA and IIB as compared to healthy controls (Group--I) at baseline. After 6 weeks the change in pre and post therapy values of FBS, PPBS and MNCV (median and common peroneal nerve) were highly significant (P = < 0.001) for group IIB alone with insignificant change (P = > 0.05) in group IIA. No improvement (P = > 0.05) in autonomic dysfunction was observed in either groups. Therefore, oral zinc supplementation helps in achieving better glycemic control and improvement in severity of peripheral neuropathy as assessed by MNCV.

Efectividad de baclofeno en el tratamiento de espasticidad de origen cerebral / Usefulness of baclofen in spasticity of brain origin

Propósito: comparar la efectividad de baclofeno y un placebo para disminuir la espasticidad, mejorar la función motora, autonomía funcional y participación en sus cuidados diarios. Diseño: prospectivo, cruzado, de administración de baclofeno (1 a 2 mg . kg . día) y placebo (tiamina, 37,5 mg . día) en dos fases de seis semanas cada una. Situación: pacientes con parálisis cerebral de una institución privada para el cuidado de inválidos, bajo control y tratamiento en la unidad de neurología pediátrica del Hospital Clínico San Borja-Arriarán, en Santiago metropolitano. Veinte personas de 3 a 26 años de edad, con parálisis cerebral espástica. Mediciones y resultados: en la evaluación inicial del tono muscular con la escala de uno (normal) a cinco puntos (rigidez severa) de Ashworth, todos los pacientes tenían puntajes de espasticidad iguales o mayores a 3, lo que no cambió bajo placebo, pero disminuyó significativamente durante el tratamiento con baclofeno, en que el tono bajó de 10 casos a puntaje 2 (prueba de Wilcoxon p < 0,05). En nueve pacientes mejoraron la movilidad espontánea y el desempeño en sus cuidados de rutina en la fase de baclofeno. No se registraron cambios en la función motora gruesa. Los beneficios fueron mayores en los pacientes con menores deterioros intelectual y motor, en todos los aspectos. El baclofeno puede ser un tratamiento auxiliar útil en pacientes con parálisis cerebral espástica y merece ser evaluado en ensayos de mayor duración

Isoniazid induced neuropathy in slow versus rapid acetylators: an electrophysiological study.

Clinical, biochemical and nerve conduction studies were performed in 100 cases of tuberculosis taking isonicotinic acid hydrozide (isoniazid) for more than 12 weeks. Electro-physiological studies were carried out in a similar number of normal age and sex matched controls. In 16 percent of cases an abnormality was documented in the motor nerve conduction velocity, amplitude and terminal latency of the common peroneal, ulnar and median nerves; of these, only two patients had objective evidence of neuritis. The occurrence of isoniazid neuropathy was found to be more in the fourth decade of life (10 of 16), in those who had taken the drug for over six months (13 of 16), and in 'slow' inactivators (10 of 16).

A study of nerve conduction velocity in patients on diphenylhydantoin therapy.

Peripheral nerve conduction studies were performed in 30 epileptics, treated with DPH and results were compared with age and sex matched controls. There was significant reduction in the amplitude of sensory nerve action potential of median (26.65 +/- 14.71 mu v) and superficial radial nerve (25.65 +/- 10.08 mu v) (p < 0.001) in DPH treated group as compared to controls, (median nerve 42.64 +/- 15.93 uv and superficial radial nerve 40.72 +/- 24.74 mu v). The results suggest that DPH causes a subclinical distal axonal neuropathy in therapeutic dosage.

Inhibition by dopamine of the neurotransmission in the rat vas deferens

Se investigaron los efectos de agonistas y antagonistas alfa -adrenérgicos y dopaminérgicos sobre los receptores presinápticos de la porción prostática del conducto defrerente de rata. La variable estudiada fue el primer componente (250 ms) de la respuesta motora inducida por estimulación eléctrica de campo (pulso único). Con el objeto de bloquear los sitios de pérdida de las aminas, todos los experimentos se llevaron a cabo en presencia de cocaína 30 micronmol/l e hidrocortisona 28 micronmol/l. Asimismo, se empleó 1-propranolol 0.3 micronmol/l para bloquear los receptores ß -adrenérgiocs. Clonidina, noradrenalina (NA) y dopamina (DA) inhibieron la respuesta motora inducida por la aplicación de un pulso eléctrico. Este efecto fue, para los tres agonistas, dependiente de las concentraciones utilizadas. DA fue 10 y 10**4 veces menos potente que NA y clonidina respectivamente. El agonista selectivo D2, LY 141865, no logró inhibir la respuesta motora inclusive a una alta concentración (30 micronmol/l). Yohimbina (0.1, 0.3 y 1 micronmol/l) antagonizó en forma competitiva el efecto inhibitorio de clonidina, NA y DA, presentando valores similares de -log KB (7.57, 7.68 y 7.09 respectivamente). De manera análoga, idaxozán 0.03 micronmol/l bloqueó el efecto inhibitorio de DA con una potencia similar (- log KB = 7.81) a la de yohimbina. Por otra parte, pimozide 0.21 micronmol/l y Schering 23390 3 micronmol/l antagonizaron el efecto inhibitorio de DA, mostrando una potencia menor que los antagonistas alfa2 -adrenérgicos...

The Effect of Strychnine on Membrane Properties of Spinal Motoneurons in the Cat

Strychnine (Stry.) has been used, as an instrument for studies of experimental epilepsy, though its precise mode of action has remained obscure. One mechanism of action was partially clarified in 1954 ,by the demonstration that subconvulsive doses of Stry. reduce the amplitude of inhibitory postsynaptic potentials (IPSPs) in the cat's spinal motoneurons (MN). Because of the rapid onset of its action and the absence of effects upon monosynaptic excitatory postsynaptic potentials (EPSPs), it was proposed that Stry. competed with some unidentified transmitter for inhibitory receptor sites on the postsynaptic membrane. Electrophoresis of Stry. is known to block the inhibitory effects of glycine, a likely candidate as an inhibitory transmitter on MN in the cat spinal cord. A Stry. resistant inhibition seems to exist not only in the higher portion of the CNS, but also for the spinal MN. Gamma amino butyric acid (GABA) is a candidate for this synaptic transmitter. In Nembutal anesthetized cat, intracellular recording of spinal MN was performed during Stry. induced seizure. To conclude, it can be said that there were no consistant changes in the MN action potential which would reflect an action of Stry. upon MN's membrane properties important to seizure generation. It is still to be resolved whether the increase in polysynaptic EPSP amplitude is due to a Stry. effect upon the membrane properties of excitatory interneurons or to an effect only upon the inhibitory as well as the EPSPs.