The protective effects of Citrus aurantium flower extract against 6-hydroxydopamine-mediated cell damage in human neuroblastoma SH-SY5Y cells / Los efectos protectores del extracto de flor de Citrus aurantium contra el daño celular mediado por 6-hidroxidopamina en células humanas de neuroblastoma SH-SY5Y

Parkinson's disease (PD) is described as a neurological condition, resulting from continuous degeneration of dopaminergic neurons. Currently, most treatments for neurodegenerative diseases are palliative. In traditional Iranian medicine, Citrus aurantium flower extract is used to treat some neural diseases, such as sleep disorders and anxiety. The tendency towards the use of medicinal herbs for the treatment of diseases (eg, seizure) is growing. Accordingly, we evaluated the antioxidant effects of C. aurantium flowers and analyzed their protective effects against 6-hydroxydopamine (6-OHDA)-mediated oxidative stress. In this study, 150 mM of 6-OHDA was used to induce cellular damage. Also, MTT assay was performed to analyze cellular viability. Fluorescence spectrophotometry was performed to measure the intracellular reactive oxygen species (ROS) and calcium levels. Based on the findings, 6-OHDA could reduce cell viability. We also analyzed the effects of C. aurantium against neurotoxicity. The intracellular levels of ROS and calcium greatly improved in cells exposed to 6-OHDA. SH-SY5Y cell incubation with C. aurantium (400 and 600 mg/mL) induced protective effects and decreased the biochemical markers of cell apoptosis. According to the findings, C. aurantium showed protective effects against neurotoxicity, caused by 6-OHDA; these protective properties were accompanied by antiapoptotic features. According to the findings, it seems that hydromethanolic C. aurantium extract can be used to prevent seizures.

La enfermedad de Parkinson (EP) se describe como una afección neurológica que resulta de la degeneración continua de las neuronas dopaminérgicas. Actualmente, la mayoría de los tratamientos para las enfermedades neurodegenerativas son paliativos. En la medicina tradicional iraní, el extracto de flor de Citrus aurantium se usa para tratar algunas enfermedades neurológicas, como los trastornos del sueño y la ansiedad. La tendencia hacia el uso de las medicinas para el tratamiento de enfermedades (por ejemplo, convulsiones) está creciendo. Por consiguiente, el objetivo de este trabajo consistió en evaluar los efectos antioxidantes de las flores de C. aurantium y analizar sus efectos protectores contra el estrés oxidativo mediado por la 6- hidroxidopamina (6-OHDA). En este estudio, se usó 150 mM de 6-OHDA para inducir daño celular. Además, se realizó un ensayo de MTT para analizar la viabilidad celular. La espectrofotometría de fluorescencia se realizó para medir las especies reactivas de oxígeno (ROS) intracelulares y los niveles de calcio. En base a los hallazgos, 6-OHDA podría reducir la viabilidad celular. También analizamos los efectos de C. aurantium contra la neurotoxicidad. Los niveles intracelulares de ROS y calcio se expandieron a las células expuestas a 6-OHDA. La incubación de células SH-SY5Y con C. aurantium (400 y 600 mg / ml) indujo efectos protectores y disminuyó los marcadores bioquímicos de la apoptosis celular. De acuerdo con los hallazgos, C. aurantium mostró efectos protectores contra la neurotoxicidad, causada por 6-OHDA; estas propiedades protectoras fueron acompañadas por características antiapoptóticas. Según los hallazgos, parece que el extracto hidrometanólico de C. aurantium se puede usar para prevenir las convulsiones.

Lesion of Subthalamic Nucleus in Parkinsonian Rats: Effects of Dopamine D1 and D2 Receptor Agonists on the Neuronal Activities of the Substantia Nigra Pars Reticulata

OBJECTIVE: It was hypothesized that dopamine agonist administration and subthalamic nucleus (STN) lesion in the rat might have a synergistic effect on the neuronal activities of substantia nigra pars reticulata (SNpr) as observed in patients with Parkinson's disease. The effects of SKF38393 (a D1 receptor agonist) and Quinpirole (a D2 receptor agonist) were compared in parkinsonian rat models with 6- hydroxydopamine (6-OHDA) after STN lesion. METHODS: SKF38393 and Quinpirole were consecutively injected intrastriatally. SNpr was microrecorded to ascertain the activity of the basal ganglia output structure. The effect of SKF38393 or Quinpirole injection on the firing rate and firing patterns of SNpr was investigated in medial forebrain bundle (MFB) lesioned rats and in MFB+STN lesioned rats. RESULTS: The administration of SKF38393 decreased SNpr neuronal firing rates and the percentage of burst neurons in the MFB lesioned rats, but did not alter them in MFB+STN lesioned rats. The administration of Quinpirole significantly decreased the spontaneous firing rate in the MFB lesioned rats. However, after an additional STN lesion, it increased the percentage of burst neurons. CONCLUSION: This study demonstrated that dopamine agonists and STN lesion decreased the hyperactive firing rate and the percentage of burst neurons of SNpr neurons in 6-OHDA lesioned rats, respectively. Quinpirole with STN lesion increased a percentage of burst neurons. To clear the exact interactive mechanism of D1 and D2 agonist and the corresponding location, it should be followed a study using a nonselective dopamine agonist and D1, D2 selective antagonist.

Dynamic expression of bFGF and TGFbeta2 in glomus cell grafts of carotid body in rat model of Parkinson disease / 华中科技大学学报（医学）（英德文版）

To investigate the changes in the expression of basic fibroblast growth factor (bFGF) and transforming growth factor beta 2 (TGFbeta2) in glomus cell grafts of carotid body in the rat model of 6-hydroxydopamine-induced Parkinson disease, immunohistochemical staining of bFGF and TGFbeta2 in the sections of striate body was done on the 2nd, 4th and 12th week after transplantation. The results showed that on the 2nd week after transplantation, bFGF and TGFbeta2 were not detectable in the glumous cell grafts. On the 4th week after graft, bFGF and TGFbeta2 immunoreactivity was increased within the grafts and at the graft-host interface but was restricted only to astrocytes. In the striatum surrounding the graft, bFGF was expressed persistently, while TGFbeta2 showed transient expression. It was suggested that the transient expression of TGFbeta2 was likely due more to the trauma imposed by the graft procedure than to an intrinsic. The deficiency in astrocytic bFGF early after graft may be responsible for the poor survival of grafted glomus cells of carotid body.

Differntial effect of NMDA antagonists on D1 & D2 mediated rotation responses in 6- hydroxydopamine (6-OHDA) lesioned rat

BACKGROUND & OBJECTIVES: Glutamate is a major neurotrammitter in corticostriatal, subthalamopallidal, and subthalamonigral pathways and interacts with other neurotrammitters. The study was done to investigate the effects of NMDA blockade on dopaminergic responses. METHODS: We made a unilateral Parkinson model in rats by injecting 6-hydroxydopamine into the substantia nigra. Rotational behavior was observed using apomorphine (mixed Dl/D2 agonist, 0. 5 mg/kg), SKF 38393 (Dl agonist, 1. 5 mg/kg), LY-171555 (D2 agonist, 0. I mg/kg), MK-801 (uncompetitive NMDA blocker, 0. 067 mg/kg), and memantine (non competitive NMDA blocker, 10 mg/kg). RESULTS: Contralateral rotation was induced by apomorphine (total turns for 2 hours, 1160+/-154), SKF 38393 (total turns for 3 hours, 1374+/-400), and LY 171555 (total turns for 3 hours 2316+/-395). NMDA antagonists per se induced mild ipsilateral rotation (MK 801; 587+/-131, memantine; 166+36). Apomorphine induced rotation was potentiated by MK 801 (1683+/-186, p<0.05) and memantine (170+/-264, p<0.05). SKF 38393 induced rotation tended to be potetiated by MK-801 (2451+/-741, p=0.08) and memantine (1794+/-450, p=0.21), though not statistically significant. However, LY 171555 induced rotation was reduced by MK-801 (1153+/-284, p<0.05) ad memantine (22.1+/-42.5, p<0.05). CONCLUSION: NMDA blockers act synergistically with Dl- and antagonistically with D2-mediated behavioural responses, suggesting that glutamate has different interactions with Dl- and D2 pathway.

The release of catecholamines by an endogenous factor that inhibits neuronal Na+, K(+)-ATPase

Se ha demostrado que la inhibición de la Na+, K+-ATPasa produce liberación de neurotransmisor en distintos modelos experimentales. En este laboratorio se observó previamente que una fracción soluble separada mediante Sephadex G-50 (pico II) es capaz de inhibir la actividad de Na+, K+-ATPasa pero no de otras enzimas asociadas a membranas. El objetivo del presente trabajo fue probar el efecto de la fracción pico II de cerebro sobre el contenido de neurotransmisor de las vesículas sinápticas de los nervios pineales. Se usaron ratas no inyectadas y ratas inyectadas 30 min antes con 5-hidroxidopamina (30 mg per Kg, i.p.). La 5-hidroxidopamina produce un falso neurotransmisor cuya presencia en las vesículas sinápticas se visualiza luego de la fijación con glutaraldehído-osmio como un material electrón denso que llena total o parcialmente las vesículas. En ratas no inyectadas se estudió la osmiofilia y la reacción cromafín del nucleoide electron denso. Las glándulas pineales se incubaron en solución Tyrode sin calcio en presencia y ausencia de pico II a temperatura ambiente y se estudiaron al microscopio electrónico. Cuando las glándulas de las ratas pretratadas con 5-hidroxidopamina se incubaron con pico II se observó una disminución siginificativa en el número de vesículas totalmente llenas de material electrón denso. Esto indica una reducción en el contenido de falso neurotransmisor contenido en la matriz de las vesículas sinápticas. Este efecto sobre las vesículas sinápticas no se observó en presencia de pico II invejecido, que no inhibe la Na+, K+-ATPasa. Cuando las gládulas de ratas no inyectadas se incubaron con pico II no se observaron cambios ni en la osmiofilia ni en la reacción cromafin de las vesículas sinápticas. La osmiofilia y la reacción cromafin del nucleoide electrón denso marca el sitio de acumulación de monoaminas (catecol e indolaminas en los nervios pineales). Estos resultados son coherentes con la idea de una relación entre la inhibición de la actividad de Na+, K+-ATPasa y la liberación de una fracción de neurotransmisor acumulado en los terminales nerviosos

A novel, fully automated rotometer for the study of turning behavior: comparison of results under different experimental conditions

Se describe un rotámetro totalmente automático destinado a la cuantificación del comportamiento rotatorio en ratas con lesión unilateral del sistema nigroestiado. Las partes fundamentales del rotámetro son: a) sensor compuesto a su vez por un disco perforado que reproduce la rotación del animal mediante giro homólogo y dos células infrarrojo, con emisor y receptor cada una de ellas; b) microprocesador que transforma los pulsos de las células fotoeléctricas en información computadorizada, memoriándola; c) impressora comercial conectada al microprocesador. La confiabilidad, utilidad y validez del rotámetro se ensayó en distintos grupos experimentales de ratas adultas. La destrucción unilateral de la zona compacta de la sustantia nigra con 6-hidroxidopamina o ácido Kaínico intracerebrales, produce rotación contralateral bajo administración de apomorfina (0.5 y 1 mg/Kg, s.c.). En cambio la apomorfina provoca rotación homólateral a la lesión en animales con destrucción electrolítica (1.5 mA, 15 s) de la nigra. Para obtener una actividad rotatoria significativa, la lesión electrolítica debe ubicarse en la región externa del núcleo (365+53.4 vueltas/60m en lesión externa (n=5); 97.3ñ19.5 en lesión interna (n=3); t=2.31, p<0,05. Apomorfina 0.5 mg/Kg, s.c.). En animales con lesión unilateral del caudado por ácido iboténico intracerebral, se observa rotación homolateral tanto a la apomorfina como a la bromocriptina tanto a la apomorfina como a la bromocriptina (10 y 30 mg/Kg, i.p.). Se comprueban dif

Influence of 6-hydroxydopamine on ethanol narcosis in mice

Se estudian los efectos de la administración de 6-hidroxidopamina (6-OHDA0, 100 Y 200 microng i.c.v., en la duración de la narcosis por etanol en ratones sin o con tratamiento de alfa-metil-p-tirosina (AMPT), p-cloro-fenilalanina (PCPA) o 5-hidroxitriptófano (5-HTP). La narcosis por etanol fue significativamente más prolongada en los ratones que recibieron 200 microng de 6-OHDA i.c.v. que en los testigos. La duración de la narcosis en los ratones tratados con ambas dosis de 6-OHDA fue significativamente más larga cuando éstos recibieron previamente AMPT (inhibidor de la biosíntesis de seotonina). En 5-HTP (precursor de la biosíntesis de serotonina). En cambio, en los pretratados con PCPA (inhibidor de la triptófano hidroxilasa), la 6-OHDA no modificó la duración de la narcosis por etanol. Las alcoholemias al momento de despertar no cambiaron significativamente por la 6-OHDA. Estos resultados son consistentes con la hipótesis de que la disminución de noradrenalina así como el aumento de serotonina cerebrales prolongan la narcosis por etanol y, en cambio, el aumento de noradrenalina o la disminución de serotonina en el cerebro reducen la narcosis por etanol

Xylazine antinociception in mice: evidence for mediation by postsynaptic adrenoceptors

The influence of 6-hydroxydopamine (6-OHDA) pretreatment on zylazine (XLZ)-induced antinociception was studied in mice using the writhing test (60 mg/Kg acetic acid, ip, as the algogenic compound administered 10 min after 0.5 0.75 mg/Kg XLZ, sc). 6-OHDA (100 mgKg-1 injection-1 administered ip on days 1, 3, 5, 7, 9 and 11 after bith) did not modify XLZ- induced antinociception, suggesting that effects is mediated by postsynaptic alpha-2 adrnoceptors

Effects of both 6-hydroxydopamine-induced and electrolytic lesion of the substantia nigra on the rotational behavior and audiogenic seizures in the rat

1. Twenty-eight male albino rats were evaluted for audiogenic seizure sensitivity by systematic observation and the recording of behavior by ethological methods. The animals were subjected to high-intensity acoustic stimulation and their behavior was evaluated by reference to an audiogenic severity index (SI). Animals were classified as susceptible (S) or resistant (R) depending on the SI value. R. animals were: 1) subjected to chemical lesion of the substantia nigra compacta with 6-hydroxydopamine (60HDA), followed by SI quantitation, contralateral electolytic lesion osf the substantia nigra reticulata and new SIevaluation (N = 10) received 0,9% saline followed by SI evaluation, contralateral sham (mechanical) lesion and new SI calculation; 3) another group (N = 10) was subjected to unilateral electrolytical lesion of the substantia nigra reticulata and SI evaluation. 2. Effects of asymmetry were observed after chemical or electrolytic lesions, but these alterations correlated only with increased audiogenic sensitivity in rats with electrolytic lesions in the substantia nigra reticulada. No bhevioral changes were observed in any of the cocntrols. The amplhetamine-induced rotational behavior presented a definite left pattern (ipsilateral to the 60HDA lesion) for the animals with bilateral lesions, with an asymmetry index of 98%, whereas the sham-lesioned controls showed a 60% asymmetry index which was not significant. 3. The relationship between asymmetry and ssimultaneous audiogenic sensitivity may correspond to changes in the basal ganglia possibly in the hypersensitive postsynaotic portions of the substantia nigra reticulata efferents

Immunopharmacological studies on Picrorhiza kurroa Royle-ex-Benth. Part III: Adrenergic mechanisms of anti-inflammatory action.

Nature of adrenergic mechanisms contributing to anti-inflammatory effect of Picrorhiza kurroa suggested from earlier studies was explored in Wistar albino rats. Water soluble fraction of alcoholic extract of rhizomes (PK) potentiated castor oil-catharsis on oral administration but direct subplanter PK-injections failed to exhibit any local irritancy and oedema. Propranolol pretreatment counteracted while phentolamine enhanced anti-inflammatory effect of PK in carrageenin-induced inflammation. 6-hydroxy-dopamine pretreatment antagonised the said PK-effect and in such animals both ephedrine and isoprenaline augmented anti-inflammatory effect of PK, the former interaction being more conspicuous. PK-treatment of rats did not influence adrenaline uptake by lung slices in vitro. The results suggest that a non-neural augmentation of beta-adrenoceptor function or consequent cellular events mediates the anti-inflammatory effect of PK.

Conditioned turning and functional recovery after unilateral substantia nigra lesion in rats

In order to invetigate whether conditioned circling interferes with recovery from turning induced by unilateral substantia nigra (SN) lesion, rats were trained to turn either ipsi-or contralateral to the lesioned side before and after the lesion was made. Two yoked groups served as controls. The number of turns contralateral to the trained side was significantly lower in relation to the pre-lesion value for the ipsilateral trained group and remained so until the end of the experiment. A partial recovery was observed on the 19th post-lesion day for the contralateral trained group. The results are discussed in terms of additive effects from training and the lesion symptoms

Efecto de la 6-Hidroxidopamina intracisternal sobre la respuesta cardiovascular producida por la oclusión carotidea y la asfixia en la rata / Effect of intracisternaly administered 6-Hidroxydopamine on cardiovascular responses produced by carotid occlusion and asphixia in the rat

La 6-Hidroxidopamina (6-OHDA), 200 *gx3 dosis, inyectada en la cisterna magna de la rata, produce a los 20-30 días postratamiento una abolición de la respuesta hipertensiva a la oclusión bilateral de las carótidas y un bloqueo casi total de la hipertensión producida por la asfixia. La sensibilidad de los vasos periféricos a la noradrenalina exógena no se modificó en los animales tratados con 6-OHDA, así como tampoco se modificó la respuesta vagal bradicardizante a la hipertensión producida por la noradrenalina. El tratamiento con 6-OHDA produjo un agotamiento del 75-100 por ciento de la noradrenalina del cerebro y la médula espinal La integridad de las terminaciones noradrenérgicas del sistema nervioso central parece indispensable en la producción de la descarga simpática central originada por estimulación de los barorreceptores y quimiorreceptores de la periferia

Lipasa de lipoproteínas en cerebro. II. Ausencia de respuesta a la administración de 6-hidroxidopamina en el ratón / Cerebral lipoprotein lipase. II. Absence of response to 6-hydroxydopamine administration in the mouse

Se investigó el efecto de la administración seriada de 6-hidroxidopamina (6-OHDA) sobre la actividad de lipasa de lipoproteinas (PLP) cerebral en el ratón. La inyección intraperitoneal de 4 dosis (una por semana) de 6-OHDA, 100 mg/Kg de peso, no produjo efecto sobre la actividad de LPL cerebral ni cambios en la depleción enzimática del cerebro por la administración de heparina (100 UL/Kg de peso, vía intraperitoneal). La 6-OHDA tampoco ejerció efecto sobre la actividad LPL cerebral in vitro. Hubo una retención significativa (p<0,05) de la actividad LPL en el corazón después de la administración de heparina en animales inyectados previamente con 6-OHDA. Se sugiere la existencia de diferencias estructurales importantes entre las LPL de cerebro y corazón

Induçäo de pseudogravidez em ratas pela administraçäo intraventricular de 6-hidroxidopamina / Induction of pseudopregnancy in rats by the intraventricular administration of 6-hydroxydopamine

Procurando verificar se a destruiçäo das vias catecolaminérgicas pela 6-hidroxidopamina modificava o ciclo estral de ratas, quando injetada no ventrículo lateral, observou-se o aparecimento de um quadro de pseudogravidez. Os resultados mostraram que esses animais apresentavam uma diminuiçäo da ingestäo de alimentos que se correlacionava com o período de pseudogravidez. Vários autores descrevem este efeito com a administraçäo de drogas antidopaminérgicas e discutem os resultados em termo de interaçäo ao nível de transmissores sinápticos. No presente trabalho, mostra-se que o efeito da 6-hidroxidopamina, que poderia ser discutido como uma inibiçäo do fator inibidor da prolactina, causando pseudogravidez, pode ser originado apenas pelo estresse da privaçäo de alimentos

Studies on rectal temperature of rats in relation to seasonal air temperature and morphine administration.

The present findings demonstrate that seasonal air temperature does not only influence the basal core temperature of rats, but also modifies the physiological/pharmacological actions of drugs. Thus, at low ambient temperature, intracerebroventricular on intraperitoneal administration of morphine produces mainly hypothermia followed by a secondary rise in rectal temperature. On the other hand, at high ambient temperature, the drug produces hyperthermia only. The hypothermic response at low ambient temperature is abolished by pretreatment of rats with 6-hydroxydopamine but not with phenoxybenzamine administration. This suggests that catecholamine pathway in the central nervous system is involved in morphine induced hypothermic response. Further, the role of cholinergic neurons in such response is also indicated.

Effect of foot-electroshock stress on cholinergic activity, tissue glycogen and blood sugar in albino rats.

The immediate or 24 hr delayed effects of 1-day (1-DS) or (7-DS) foot-electroshock stress in albino rats were studied on cardiac acetylcholine (ACh), blood and cardiac cholinesterase (ChE) activities, cardiac, hepatic and muscle glycogen contents and blood sugar concentrations. The effects of physostigmine (PHY), atropine, 6-hydroxydopamine (6-HD), vagotomy and adrenalectomy on 1-DS induced changes were also studied. 1-DS produced an increase in cardiac ACh content which lasted for 24 hr but repeated stress showed phenomenon of adaptation. There seems to be activation of autonomic cholinergic system in stress. 1-DS and 7-DS produced a short-lived inhibition of blood ChE activity and 7-DS also of cardiac ChE activity. Inhibition of ChE activity was probably related to release of adrenaline from adrenal medulla. 1-DS produced hepatic and muscle glycogenolysis with slight hypoglycaemia but without any effect on cardiac glycogen. Following repeated stress there was a phenomenon of adaptation. The hepatic and muscle glycogenolysis produced by stress is due to the release of adrenaline from adrenal medulla. Normally functioning cardiac cholinergic system seems to have a protective effect on heart against stress, in the absence of which cardiac glycogenolysis is induced by stress.

Further studies on the mechanism of rise in blood pressure and tachycardia after intraventricular administration of aconitine.

Intraventricular administration of aconitine nitrate (10 mug) consistently produced hypertension and tachycardia. Peripheral vaso-constriction due to increase in central vasomomotor tone mainly responsible for hypertension whereas stimulation of central beta-receptors with sympathoadr renal discharge responsible for tachycardia.