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Depression is a psychiatric disorder that constitutes one of the leading causes of disability worldwide. 2-Phenyl-3-(phenylselanyl)benzofuran (SeBZF1) has been studied as a potential antidepressant drug, but its pharmacological action needs more investigation. Our aim was to extend information about the antidepressant-like action of SeBZF1 using the mouse tail suspension test (TST). Initial experiments investigated the mechanisms involved in the acute antidepressant-like action of SeBZF1 in male Swiss mice. For this purpose, males received noradrenergic or dopaminergic receptor antagonists before acute SeBZF1 administration (50 mg/kg, per oral). In parallel, effects of combined treatment with SeBZF1 and bupropion at sub-effective doses (1 and 3 mg/kg, respectively) were tested. The next experiments were designed to determine the acute effects of SeBZF1 in females through a dose–response curve (5–50 mg/kg). Lastly, the efficacy of a 7-day repeated treatment with SeBZF1 (1 and 5 mg/kg) in mice of both sexes and its safety were evaluated. TST and the open-field test (OFT) were employed in all behavioral experiments. Pre-administration of dopaminergic antagonists (SCH23390, a selective D1R antagonist; sulpiride, a selective D2/D3R antagonist; and haloperidol, a non-selective antagonist), but not of adrenergic α1, α2, and β-R antagonists, blocked the acute antidepressant-like effects of SeBZF1 in males. Co-administration of sub-effective doses of SeBZF1 and bupropion reduced the depressive phenotype. In addition, acute treatment with SeBZF1 at 50 mg/kg produced a reduction of female immobility. Finally, repeated treatment with SeBZF1 (1 and 5 mg/kg) was effective in causing antidepressant-like effects in both sexes. Locomotor activity, plasma transaminases, and urea levels remained unaltered after SeBZF1 exposure. Our findings provide evidence of the involvement of the dopaminergic system in the acutely antidepressant-like action of SeBZF1 in male mice and reveal the compound efficacy when acute or repeatedly administered in both sexes.

Chronic pain and depression often coexist sharing common pathological mechanisms, and available analgesics and antidepressants have demonstrated limited clinical efficacy. Evidence has demonstrated that neuronal oxidative stress, apoptosis, and also glucocorticoid receptor dysregulation facilitate the occurrence and development of both chronic pain and depression. This study evaluated the effect of the organoselenium compound m-trifluoromethyl-diphenyl diselenide [(m–CF3–PhSe)2] in the pain–depression comorbidity induced by reserpine. Mice were treated with reserpine 0.5 mg/kg for 3 days (intraperitoneal, once a day), and in the next 2 days, they were treated with (m–CF3–PhSe)2 10 mg/kg (intragastric, once a day). Thirty minutes after the last administration of (m–CF3–PhSe)2, mice were subjected to the behavioral testing. (m–CF3–PhSe)2 treatment reverted the reserpine-increased thermal hyperalgesia and depressive-like behavior observed in the hot-plate test and forced swimming test, respectively. Reserpine provoked a decrease of crossings and rearings in the open-field test, while (m–CF3–PhSe)2 presented a tendency to normalize these parameters. Reserpine and/or (m–CF3–PhSe)2 treatments did not alter the locomotor activity of mice observed in the rota-rod test. These effects could be related to modulation of oxidative stress, apoptotic pathway, and glucocorticoid receptors, once (m–CF3–PhSe)2 normalized thiobarbituric acid reactive substances and 4-hydroxynonenal modified protein levels, markers of lipoperoxidation, poly(ADP-ribose) polymerase cleaved/total ratio, and glucocorticoid receptor levels increased by reserpine in the hippocampus. Considering that pain–depression dyad is a complex state of difficult treatment, this organoselenium compound could raise as an interesting alternative to treat pain–depression condition.

Obesity is considered one of the major global health problems and increases the risk of several medical complications, such as diabetes and mental illnesses. The present study investigated the effect of 7-chloro-4-(phenylselanyl) quinoline (4-PSQ) on obesity parameters, behavioral and neurochemical alterations in hypothalamic obese rats. Methods: Male Wistar rats received subcutaneous neonatal injections of monosodium glutamate (MSG, 4g/kg) or saline. After the Lee Index evaluation, rats were divided into groups and treated with 4-PSQ (5 mg/kg, intragastric route) or canola oil once a day (post-natal days (PND) 60→76). Open-field, elevated plus-maze, forced swim task, object recognition/location memory, and stepdown inhibitory avoidance tasks were conducted from PND 66 to 74. On PND 76, rats were euthanized and epididymal fat, blood, cerebral cortex, andhippocampus were removed. Blood biochemical parameters and cortical/hippocampal acetylcholinesterase (AChE) and Na /K -ATPase activities were assessed. MSG increased the Lee Index characterizing the chemically induced hypothalamic obesity model. 4-PSQ reversed the increases of epididymal fat, blood glucose, and triglyceride levels caused by MSG exposure. 4-PSQ attenuated anxiety-like and depression-like behaviors induced by neonatal administrations of MSG. Memory deficits found in MSG-obese rats were reversed by treatment with 4-PSQ. Neurochemical alterations produced by MSG evidenced by stimulation ofNa+/K+-ATPase and AChE activities in the cerebral cortex and hippocampus of rats were normalized by 4-PSQ treatment. In brief, 4-PSQ therapy improved hypothalamic obesity-related parameters, as well as psychiatric symptoms, cognitive impairment, and neurochemical alterations found in obese rats.

We describe our results for the synthesis of 2′-(1,2,3-triazoyl)-acetophenones by copper catalyzed azide–alkyne cycloaddition of 2′-azidoacetophenone with alkynes. The corresponding 2′-(1,2,3-triazoyl)-acetophenones were obtained in moderate to excellent yields and according to our experiments, it was observed that ultrasound accelerates the reaction compared to conventional heating. In addition, the obtained compounds were screened by molecular docking for their possible inhibitory effect on the activity of monoamine oxidase (MAO), an enzyme responsible for the degradation of monoamine neurotransmitters. Three compounds were selected and presented an inhibitory effect on both MAO-A and B isoform activities in vitro. These new MAO inhibitors may be of interest to treat monoamine deficit related-neuropsychiatric disorders, such as depression and Parkinson's disease.

Major depressive disorder is a psychiatric disorder that requires considerable attention, since it dramatically impairs the quality of life of the sufferers. The available treatments do not have the efficacy needed, often presenting several side effects. Organoselenium compounds and benzamides have presented some pharmacological properties, among them an antidepressant-like effect. This study evaluated the antidepressant-like effect of N-(3-(phenylselanyl)prop-2-yn-1-yl)benzamide (SePB), an organoselenium compound containing a benzamide moiety, on the forced swimming test (FST) and the tail suspension test (TST) in mice, as well as the involvement of the serotonergic system in its effect. SePB, tested after different times (15–120 min) and doses (1–50 mg/kg, intragastrically (i.g.)), reduced immobility of male mice during FST and TST, without changing locomotor activity in the open-field test (OFT), demonstrating its antidepressant-like effect. SePB (10 mg/kg) also produced an antidepressant-like effect in female mice in the TST. The preadministration of the serotonin (5-HT) depletor p-chlorophenylalanine (pCPA; 100 mg/kg, intraperitoneal route (i.p.) once daily for 4 days) prevented the anti-immobility effect of SePB, indicating that the serotonergic system is involved in the SePB antidepressant-like effect. The preadministration of the selective serotonergic receptor antagonists WAY100635 (0.1 mg/kg, subcutaneous route (s.c.), a selective 5-HT1A receptor antagonist), ketanserin (1 mg/kg, i.p., a 5-HT2A/2C receptor antagonist), and ondansetron (1 mg/kg, i.p., a selective 5-HT3 receptor antagonist) also prevented the anti-immobility effect of SePB, demonstrating that these receptors are involved in the antidepressant-like effect of SePB. The search for new antidepressants drugs is a noteworthy goal. This study has described a new compound with an antidepressant-like effect, whose mechanism of action is related to modulation of the serotonergic system.

Glutaric acidaemia type I (GA-I) is a cerebral organic disorder characterized by the accumulation of glutaric acid (GA) and seizures. As seizures are precipitated in children with GA-I and the mechanisms underlying this disorder are not well established, we decided to investigate the role of nitric oxide (NO) in GA-induced convulsive behaviour in pup rats. Pup male Wistar rats (18-day-old) were anesthetized and placed in stereotaxic apparatus for cannula insertion into the striatum for injection of GA. The experiments were performed 3 days after surgery (pup rats 21-day-old). An inhibitor of NO synthesis (N-G-nitro-l-arginine methyl ester-L-NAME, 40 mg/kg) or saline (vehicle) was administered intraperitoneally 30 min before the intrastriatal injection of GA (1 µl, 1.3 µmol/striatum) or saline. Immediately after the intrastriatal injections, the latency and duration of seizures were recorded for 20 min. The administration of L-NAME significantly increased the latency to the first seizure episode and reduced the duration of seizures induced by GA in pup rats. The administration of the NO precursor l-arginine (L-ARG; 80 mg/kg) prevented the effects of L-NAME. Besides, GA significantly increased nitrate and nitrite (NOx) levels in the striatum of pup rats and the preadministration of L-NAME prevented this alteration. L-ARG blocked the reduction of striatal NOx provoked by L-NAME. These results are experimental evidence that NO plays a role in the seizures induced by GA in pup rats, being valuable in understanding the physiopathology of neurological signs observed in children with this organic acidaemia and to develop new therapeutic strategies.

Tyloxapol is a nonionic surfactant oligomer inductor of dyslipidemia, which in turn is a risk factor for liver damage. Selenium-based compounds have emerged as promising therapeutic candida...

Determining precisely the postmortem interval (PMI) is a key parameter for forensic researches, given that various physical, biochemical and metabolic changes begin to occur in the body after death. In the present study, the Na+/K+-ATPase, glutathione S-transferase (GST) and acetylcholinesterase (AChE) activities were evaluated. For this, male adult Swiss mice were killed by isoflurane inhalation anesthesia and divided into four groups according to time of death (0, 6, 24 and 48 h). The brain, liver, kidney and skeletal muscle tissues were removed. Our results revealed that at the time of 6 h, there was a decrease on Na+/K+-ATPase and GST activities in the brain and liver tissues, respectively. In addition, at this time point, an increase on renal GST activity was verified. At the time of 24 h, an increase on the cerebral AChE and renal GST activities was observed, while the cerebral Na+/K+-ATPase activity was decreased. Forty-eight hours after death, cerebral Na+/K+-ATPase and renal GST activities remained decreased and increased, respectively. In addition, no alteration was observed on the GST activity in the skeletal muscle and brain (in PMIs evaluated). The present study revealed that the brain and kidney (at the times of 24 and 48 h) were the tissues that suffered the most changes in almost all the enzymes evaluated. Our results demonstrated that enzyme activity assessments are reliable, easy-to-perform and low-cost determinations, and could be promising postmortem markers.

Some brain diseases are associated with oxidative stress and altered monoamine oxidase (MAO) activity. The objective of this study was to evaluate the antioxidant and neuroprotective actions through MAO inhibition of 3-(pyridin-2-yl)-2-(pyridine-2-ylimino) thiazolidin-4-one (PPIT, a synthetic molecule containing a thiazolidinone nucleus), as well as its effects on toxicity parameters in Swiss female mice. Five in vitro assays were carried out to verify the PPIT antioxidant capacity: protein carbonylation (PC), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picryl-hydrazil (DPPH), ferric ion (Fe3+ ) reducing antioxidant power (FRAP), and superoxide dismutase (SOD)-like activity. The results showed that PPIT reduced the level of PC in the homogenate of the brain. This compound did not demonstrate SOD mimetic activity, but it acted as a free radical scavenger (ABTS and DPPH) and exhibited reducing activity in the FRAP assay. In addition, the effects of PPIT on cerebral MAO activity (MAO-A and B isoforms) were investigated in vitro. Our data revealed inhibition of the MAO-B activity by PPIT with no effects on MAO-A. Lastly, an acute oral toxicity test was conducted in mice. No changes in food intake, body weight, and biochemical markers of kidney and liver damage were detected in mice treated with a high dose of PPIT (300 mg/kg). In conclusion, the present study demonstrated that PPIT exhibits antioxidant activity and selectively inhibits the MAO-B isoform without causing apparent toxicity. These findings suggest PPIT as a potential therapeutic candidate to be tested in preclinical models of brain diseases involving perturbations of MAO-B activity and redox status.

Obesity is considered one of the major global health problems and increases the risk of several medical complications, such as diabetes and mental illnesses.The present study investigated the effect of 7-chloro-4-(phenylselanyl) quinoline (4-PSQ) on obesity parameters, behavioral and neurochemical alterations in hypothalamic obese rats.Male Wistar rats received subcutaneous neonatal injections of monosodium glutamate (MSG, 4g/kg) or saline. After the Lee Index evaluation, rats were divided into groups and treated with 4-PSQ (5 mg/kg, intragastric route) or canola oil once a day (post-natal days (PND) 60→76). Open-field, elevated plus-maze, forced swim task, object recognition/location memory, and stepdown inhibitory avoidance tasks were conducted from PND 66 to 74. On PND 76, rats were euthanized and epididymal fat, blood, cerebral cortex, andhippocampus were removed. Blood biochemical parameters and cortical/hippocampal acetylcholinesterase (AChE) and Na /K -ATPase activities were assessed.MSG increased the Lee Index characterizing the chemically induced hypothalamic obesity model. 4-PSQ reversed the increases of epididymal fat, blood glucose, and triglyceride levels caused by MSG exposure. 4-PSQ attenuated anxiety-like and depression-like behaviors induced by neonatal administrations of MSG. Memory deficits found in MSG-obese rats were reversed by treatment with 4-PSQ. Neurochemical alterations produced by MSG evidenced by stimulation ofNaIn brief, 4-PSQ therapy improved hypothalamic obesity-related parameters, as well as psychiatric symptoms, cognitive impairment, and neurochemical alterations found in obese rats.

RESUMEN Introducción: Aproximadamente, el 20 % de los pacientes con síndrome radicular lumbosacro crónico no responden a las inyecciones epidurales de esteroides. La radiofrecuencia pulsada del ganglio de la raíz dorsal (GRD) es una alternativa terapéutica en ellos. Objetivos: Evaluar el efecto analgésico de la radiofrecuencia pulsada del GRD en pacientes con síndrome radicular lumbosacro crónico, refractario a los esteroides epidurales. Material y método: 31 pacientes con síndrome radicular lumbosacro crónico que no respondieron a dos inyecciones epidurales de esteroides fueron tratados con radiofrecuencia pulsada del GRD a 45 V y 42 °C, en 2 ciclos de 120 segundos. Se utilizó el Inventario Abreviado de Dolor para evaluar los resultados. Se consideró una respuesta satisfactoria al procedimiento una disminución de dos puntos en la escala verbal numérica (EVN) evaluada en la pregunta 6 del inventario abreviado de dolor. Los índices de intensidad y de interferencia fueron calculados antes y después del tratamiento. Resultados: La EVN se redujo de 7,7 ± 2,2 a 5,9 ± 3 (p < 0,01). Los índices de intensidad e interferencia disminuyeron de 7,1 ± 1,5 a 5,9 ± 2,1 (p < 0,01) y 7,1 ± 1,9 a 6,0 ± 2,3 (p < 0,02) respectivamente. 12 de los 30 pacientes (40 %) presentaron una respuesta analgésica satisfactoria. En estos, la EVN disminuyó de 8,0 ± 1,5 a 3,8 ± 2,6 y los índices de intensidad e interferencia de 7,4 ± 1,3 a 3,9 ± 1,5 (p < 0,0001) y 7,7 ± 1,9 a 4,9 ± 2,7 (p = 0,002), respectivamente. Conclusiones: La aplicación de radiofrecuencia pulsada en el GRD reduce en forma discreta pero estadísticamente significativa la intensidad del dolor y su interferencia funcional en pacientes con síndrome radicular lumbosacro refractario a las inyecciones epidurales de esteroides, al mes de realizada. En aproximadamente el 40 % se obtuvieron respuestas analgésicas satisfactorias que, en algunos casos, se extendió a tres meses tras realizar el procedimiento. ABSTRACT Introduction: Approximately 20 % of patients with chronic lumbosacral radicular syndrome do not respond to epidural steroid injections. Pulsed radiofrequency of the dorsal root ganglion (DRG) is proposed as an alternative treatment. Objetive: To evaluate the analgesic effect of pulsed radiofrequency of the DRG in patients with chronic lumbosacral radicular syndrome, refractory to epidural steroid injections. Patients and method: 31 patients with chronic lumbosacral radicular syndrome that failed to at least two epidural steroid injections, received pulsed radiofrequency of the DRG, utilizing two cycles of 120 seconds, 45 V and 42 °C. Evaluation was carried out a month later. Brief Pain Inventory was applied before procedure and one month later. A reduction of 2 points in the verbal numerical scale (VNS) assessed with the question 6 of the Brief Pain Inventory, was considered a satisfactory analgesic response. Intensity and Interference Scores were calculated. Results: The VNS score decreased from 7.7 ± 2,2 to 5.9 ± 3 (p < 0.01). Intensity and Interference Scores were reduced from 7.1 ± 1.5 to 5.9 ± 2.1 (p < 0.01) and 7.1 ± 1.9 to 6.0 ± 2.3 (p < 0.02) respectively. In 12 patients (40 %) a satisfactory analgesic response was observed. In these patients the VNS decreased from 8.0 ± 1.5 to 3.8 ± 2.6. Intensity and Interference Scores were reduced from 7.4 ± 1.3 to 3.9 ± 1.5 (p < 0.0001) y 7.7 ± 1.9 to 4.9 ± 2,7 (p = 0.002) respectively. Conclusions: DRG pulsed radiofrequency produce a mild but statistically significant reduction in VNS and pain interference, in patients with chronic lumbosacral radicular syndrome. However, in 40 % of the patients a satisfactory analgesic effect was observed. In some of them this changes persist after 3 months of the procedures.

Monoaminergic and oxidative dysfunctions have been reported to play a role in depression. The present study investigated the antioxidant potential as well as the antidepressant-like action of 2-phenyl-3-(phenylselanyl)benzofuran (SeBZF1) in male Swiss mice. Time and dose-response curves were analyzed with the forced swim (FST) and tail suspension (TST) tests, in which SeBZF1 elicited antidepressant-like effects. Serotonergic mechanisms were investigated in the TST. The pre-administration of WAY100635 (selective 5-HT1A receptor antagonist, 0.1 mg/kg, subcutaneous route), ketanserin (5-HT2A/2C receptor antagonist, 1 mg/kg, intraperitoneal route, i.p.), and chlorophenylalaninemethyl ester (p-CPA) (selective tryptophan hydroxylase inhibitor, 100 mg/kg, i.p., for 4 days), but not of ondansetron (selective 5-HT3 receptor antagonist, 1 mg/kg, i.p.), abolished the antidepressant-like action of SeBZF1 (50 mg/kg, intragastric route, i.g.). Co-administration of sub-effective doses of SeBZF1 (1 mg/kg, i.g.) and fluoxetine (5 mg/kg, i.p., selective serotonin reuptake inhibitor) was effective in producing anti-immobility effects in the TST, revealing a synergistic effect. Besides, p-CPA induced hippocampal oxidative stress, characterized by a reduction of total thiols and lipoperoxidation, which was reversed by SeBZF1 (50 mg/kg). The in vitro screening of the antioxidant action of SeBZF1 in brain tissue reinforced these results. Lastly, SeBZF1 did not cause systemic toxicity at a high dose (300 mg/kg). In summary, the present study demonstrated that SeBZF1 exerted antidepressant-like action in male mice which appears to be mediated by the serotonergic system. Moreover, SeBZF1 elicited in vitro antioxidant action in brain tissue, attenuated the hippocampal oxidative damage induced by 5-HT depletion in mice and showed no toxic signs.

The aim of this study was to investigate whether (E)-2-benzylidene-4-phenyl-1,3-diselenole (BPD) protects against hepatotoxicity induced by thioacetamide (TAA). On the first day of treatment, male adult Wistar rats received BPD (10 or 50 mg·kg–1). On the second day, the rats received a single intraperitoneal injection of TAA (400 mg·kg–1). Twenty-four hours after TAA administration, biochemical determinations and liver histological analysis were carried out. BPD (50 mg·kg–1) reduced plasma aspartate and alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase activities increased by TAA exposure. Treatment with BPD was effective against increased lipid peroxidation levels and attenuated a decrease in hepatic reduced glutathione and ascorbic acid levels as well as an inhibition of glutathione peroxidase activity caused by TAA exposure. The higher dose of BPD protected against the inhibition of hepatic δ-aminolevulinic dehydratase activity induced by TAA. Finally, histopathological examination of the liver showed that BPD markedly ameliorated TAA-induced hepatic injury. In conclusion, BPD protected against hepatotoxicity and oxidative stress caused by TAA exposure in rats.

The aim of the present study was to investigate the effects of SCH58261, a selective adenosine A2A receptor antagonist, on striatal toxicity induced by 3-nitropropionic acid (3-NP) in rats. The experimental protocol consisted of 10 administrations (once a day) of SCH58261 (0.01 or 0.05 mg/kg/day, intraperitoneal, i.p.). From 7th to 10th day, 3-NP (20 mg/kg/day, i.p.) was injected 1 h after SCH58261 administration. Twenty-four hours after the last 3-NP injection, the body weight gain, locomotor activity (open-field test), motor coordination (rotarod test), striatal succinate dehydrogenase (SDH) activity and parameters linked to striatal oxidative status were evaluated in rats. The marked body weight loss resulting from 3-NP injections in rats was partially protected by SCH 58261 at both doses. SCH 58261 at the highest dose was effective against impairments on motor coordination and locomotor activity induced by 3-NP. SCH 58261 was unable to restore the inhibition of SDH activity caused by 3-NP. In addition, the increase in striatal reactive species (RS) levels, depletion of reduced glutathione (GSH) content and stimulation of glutathione reductase (GR) activity provoked by 3-NP injections were alleviated by both doses of SCH 58261. The highest dose of SCH 58261 was also effective in attenuating the increase of protein carbonyl levels as well as the inhibition of glutathione peroxidase (GPx) activity in rats exposed to 3-NP. Our results revealed that reduction of oxidative stress in rat striatum by adenosine A2A receptor antagonism contributes for alleviating 3-NP-induced toxicity.

We describe herein a new approach to prepare unprecedented bioactive indolizine motifs decorated with organosulfur and organoselenium groups. A total of 12 1-sulfanylindolizines and 2 1-selanylindolizines were prepared in excellent yields by an intramolecular annulation of easily prepared chalcogen-containing pyridinium salts. The reaction is fast (1 h at 70 °C or 5 min under sonication) and transition-metal-free, using glycerol as a green solvent.

Determining precisely the postmortem interval (PMI) is a key parameter for forensic researches, given that various physical, biochemical and metabolic changes begin to occur in the body after death. In the present study, the Na

Preliminary findings suggest that food intake reduction induced by p-chloro-diphenyl diselenide [(p-ClPhSe)2] in rats is mediated by a satiating action; however, additional experiments are necessary to clarify its actions. The purpose of this study was to investigate the effects of diets supplemented with (p-ClPhSe)2 on feeding behavior of rats as well as the (p-ClPhSe)2 effectiveness in producing aversive reactions or specific flavor. The results demonstrated that behavioral satiety sequence (BSS) was preserved in animals exposed to (p-ClPhSe)2-supplemented diets (0.01 and 0.1%) and associated with a shift of the onset of resting to the left indicating a satiating action at the first contact. In addition, the frequency, the mean duration and the mean size of meals were decreased in rats exposed to a 0.1% (p-ClPhSe)2 diet. Alternatively, a second contact with a 0.01% (p-ClPhSe)2 diet caused disruption of BSS and pronounced changes in the meal pattern, suggesting that it produces aversiveness. In fact, rats developed a significant taste aversion to the saccharin solution after receiving the administration of (p-ClPhSe)2 (1 and 10mg/kg; i.p.). Lastly, a diet containing 0.1% of (p-ClPhSe)2 seems to alter the palatability of food given that rats had a preference for the control diet. The findings of the present study suggest that (p-ClPhSe)2 reduced the food intake of rats by inducing a satiating action at the first contact, but it also produced aversive reactions when rats were re-exposed to it. A specific flavor seems also to contribute to (p-ClPhSe)2 suppressant effects on feeding.

Monosodium glutamate (MSG) is a neuroexcitatory amino acid commonly used as flavoring of foods. MSG neonatal administration to animals leads to behavioral and physiological disorders in adulthood, including increased pain sensitivity. This study aimed to investigate the effect of diphenyl diselenide (PhSe)2, an organoselenium compound with pharmacological properties already documented, on nociception induced by MSG. Newborn Wistar rats received 10 subcutaneous injections of MSG at a dose of 4.0g/kg or saline (once daily). At the 60th day of life, the rats were daily treated with (PhSe)2 (1mg/kg) or vehicle (canola oil) by the intragastric route for 7 days. The behavioral tests (locomotor activity, hot plate, tail-immersion and mechanical allodynia) were carried out. Ex vivo assays were performed in samples of hippocampus to determine Na(+), K(+)-ATPase and Ca(2+)-ATPase activities, cytokine levels and [(3)H]glutamate uptake. The results demonstrated that MSG increased nociception in the hot plate test and in the mechanical allodynia stimulated by Von-Frey hair but did not alter the tail immersion test. (PhSe)2 reversed all nociceptive behaviors altered by MSG. MSG caused an increase in Na(+),K(+)-ATPase and Ca(2+)-ATPase activities and in pro-inflammatory cytokine levels and a decrease in the anti-inflammatory cytokine and in the [(3)H]glutamate uptake. (PhSe)2 was effective in reversing all alterations caused by MSG. The results indicate that (PhSe)2 had a potential antinociceptive and anti-inflammatory action in the MSG model.

The aim of the present study was to investigate the effects of SCH58261, a selective adenosine A