Exercise Attenuates Anabolic Steroids-Induced Anxiety via Hippocampal NPY and MC4 Receptor in Rats.

The aim of our study was to evaluate the effects of chronic administration of nandrolone-decanoate (ND) or testosterone-enanthate (TE) in supraphysiological doses and a prolonged swimming protocol, alone and in combination with ND or TE, on anxiety-like behavior in rats. We investigated the immunohistochemical alterations of the hippocampal neuropeptide Y (NPY) and melanocortin 4 receptor (MC4R) neurons, as a possible underlying mechanism in a modulation of anxiety-like behavior in rats. Both applied anabolic androgenic steroids (AASs) induced anxiogenic effect accompanied with decreased serum and hippocampal NPY. The exercise-induced anxiolytic effect was associated with increased hippocampal NPY expression. ND and TE increased the number of MC4R, while the swimming protocol was followed by the reduction of MC4R in the CA1 region of the hippocampus. However, NPY/MC4R ratio in hippocampus was lowered by AASs and elevated by exercise in all hippocampal regions. An augmentation of this ratio strongly and positively correlated to increased time in open arms of elevated plus maze, in the context that indicates anxiolytic effect. Our findings support the conclusion that alterations in both hippocampal NPY and MC4R expression are involved in anxiety level changes in rats, while their quantitative relationship (NPY/MC4R ratio) is even more valuable in the estimation of anxiety regulation than individual alterations for both NPY and MC4R expression in the hippocampus.

The Impact of Hippocampal Sex Hormones Receptors in Modulation of Depressive-Like Behavior Following Chronic Anabolic Androgenic Steroids and Exercise Protocols in Rats.

The aim of this study was to evaluate alterations in depressive-like behaviors in rats following chronic administration of a supraphysiological dose of anabolic androgenic steroids (AASs) as well as exposure to a prolonged exercise protocol. The role of hippocampal sex hormones receptors in the modulation of depressive-like behavior was also assessed. A total of 48 male Wistar albino rats were divided into six groups: control, exercise (1 h/day, five consecutive days), nandrolone-decanoate (ND, 20 mg/kg/week, in a single dose), exercise plus ND, testosterone-enanthate (TE, 20 mg/kg/week, in a single dose), and exercise plus TE. After the 6-week protocols were complete, the rats underwent behavioral testing in the tail suspension test (TST). Rats were sacrificed for the collection of blood samples, to determine sex hormones levels, and isolation of the hippocampus, to determine [androgen receptors (AR) and estrogen receptors α (ERα)] expression. ND and TE treatment induced significant depressive-like behavior, opposing the antidepressant effect of exercise. Chronic TE administration elevated testosterone (T) and dihydrotestosterone (DHT) serum levels, and this was augmented by exercise. In contrast, ND and exercise alone did not alter T or DHT levels. There were no changes in serum estradiol levels in any of the groups. Immunohistochemical analysis showed that exercise reduced AR immunoreactivity in all hippocampal regions and increased the ERα expression in the CA1, dentate gyrus (DG), and total hippocampal sections, but not in the CA2/3 region. AASs administration increased AR expression in all hippocampal regions, although not the total hippocampal section in the TE group and did not significantly decrease ERα. The hippocampal AR/ERα expression index was lowered while parvalbumin (PV)-immunoreactivity was enhanced by exercise. AASs administration increased the AR/ERα index and reduced PV-immunoreactivity in the hippocampus. The number of PV-immunoreactive neurons negatively correlated with the antidepressant effects and the AR/ERα ratio. Our results suggest a potential role of the numerical relationship between two sex hormones receptors (stronger correlation than for each individual receptor) in the regulation of depressive-like behavior via the hippocampal GABAergic system in rats, which allow better understanding of the hippocampal sex hormones receptors role in modulation of depressive-like behavior.

The role of galectin-3 in modulation of anxiety state level in mice.

Galectin-3 (Gal-3), a member of lectin family that binds to oligosaccharides, is involved in several biological processes, including maturation and function of nervous system. It had been reported that Gal-3 regulates oligodendrocytes differentiation and that Gal-3/Toll-like receptor-4 (TLR4) axis is involved in neuroinflammation. As both, central nervous system (CNS) maturation and neuroinflammation may affect behavior, the principle aim of this study was to examine the effects of Gal-3 gene deletion on behavior. Here we provide the evidence that Gal-3 deficiency shows clear anxiogenic effect in mature untreated animals (basal conditions). This was accompanied with lower interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) relative gene expression and hippocampal content, with no effect on TLR4 expression. Gal-3 deficiency was also accompanied with lower brain-derived neurotrophic factor (BDNF) relative gene expression and immunoreactivity in hippocampus (predominantly in CA1 region). Besides, the Gal-3 gene deletion resulted in attenuation of the hippocampal relative gene expression of GABA-A receptor subunits 2 and 5 (GABA-AR2S and GABA-AR5S), On the other hand, Gal-3 deficiency attenuates LPS-induced neuroinflammation. The anxiogenic effect of acute neuroinflammation was accompanied with increased hippocampal IL-6, TNF-α and TLR4 gene expression, as well as decreased gene and immunohistochemical BDNF expression in hippocampus, with significant decline in GABA-AR2S in wild type (WT) mice in comparison to basal conditions. Gal-3 gene deletion prevented the increase in IL-6, the decline in BDNF gene expression and immunoreactivity, and reduction in hippocampal GABA-AR2S, and therefore attenuated the anxiogenic effect of neuroinflammation. In summary, our data demonstrate that apparently opposite effects of Gal-3 deficiency on anxiety levels (anxiogenic effect under basal conditions and anxiolytic action during neuroinflammation) seem to be related to the shift in IL-6, TNF-α and hippocampal BDNF.

The anxiolytic effects of atorvastatin and simvastatin on dietary-induced increase in homocysteine levels in rats.

The aim of this study was to evaluate the effects of atorvastatin and simvastatin on behavioral manifestations that followed hyperhomocysteinemia induced by special dietary protocols enriched in methionine and deficient in B vitamins (B6, B9, B12) by means of alterations in anxiety levels in rats. Simultaneously, we investigated the alterations of oxidative stress markers in rat hippocampus induced by applied dietary protocols. Furthermore, considering the well-known antioxidant properties of statins, we attempted to assess their impact on major markers of oxidative stress and their possible beneficial role on anxiety-like behavior effect in rats. The 4-week-old male Wistar albino rats were divided (eight per group) according to basic dietary protocols: standard chow, methionine-enriched, and methionine-enriched vitamins B (B6, B9, B12) deficient. Each dietary protocol (30 days) included groups with atorvastatin (3 mg/kg/day i.p.) and simvastatin (5 mg/kg/day i.p.). The behavioral testing was performed in the open field and elevated plus maze tests. Parameters of oxidative stress (index of lipid peroxidation, superoxide dismutase, catalase activity, glutathione) were determined in hippocampal tissue samples following decapitation after anesthesia. Methionine-load dietary protocols induced increased oxidative stress in rat hippocampus, which was accompanied by anxiogenic behavioral manifestations. The methionine-enriched diet with restricted vitamins B intake induced more pronounced anxiogenic effect, as well as increased oxidative stress compared to the methionine-load diet with normal vitamins B content. Simultaneous administration of statins showed beneficial effects by means of both decreased parameters of oxidative stress and attenuation of anxiety. The results obtained with simvastatin were more convincible compared to atorvastatin.

Phytochemical analysis and anti-inflammatory effects of Filipendula vulgaris Moench extracts.

Filipendula vulgaris Moench (dropwort) is used in traditional medicine for relieving various inflammation-related diseases. In the present study, the phytochemical profile of F. vulgaris aerial part (FVA) and root (FVR) methanolic extracts was evaluated by LC-DAD-HRMS analysis. Furthermore, their in vitro and in vivo anti-inflammatory effects, as well as their potential cytotoxicity, were assessed. Results showed that the extracts mainly contain phenolics like flavonoids, hydrolyzable tannins, procyanidins, and phenolic acid derivatives, including gaultherin. No in vitro cytotoxicity was found at the highest concentration (50 µg/mL). FVA extract (50 µg/mL) significantly inhibited cyclooxygenase-1 and -2 (COX-1 and COX-2) activities in vitro (>50% inhibition), and FVR extract considerably inhibited COX-2 activity (52.5 ±â€¯2.7%) without affecting COX-2 gene expression in LPS-stimulated THP-1 cells. The extracts demonstrated prominent in vivo anti-inflammatory potential upon oral administration in rats. Especially FVA extract at 100 and 200 mg/kg significantly inhibited carrageenan-induced edema formation. From these results, it can be concluded that F. vulgaris extracts possess interesting anti-inflammatory properties.

Summer savory (Satureja hortensis L.) extract: Phytochemical profile and modulation of cisplatin-induced liver, renal and testicular toxicity.

The aim of our study was to examine the potential ameliorating effect of the methanolic extract of Satureja hortensis L. (summer savory) aerial parts against cisplatin-induced oxidative damage in renal, hepatic, and testicular tissues. S. hortensis methanol extract at the doses of 50, 100 and 200 mg/kg of body weight were orally administered to Wistar rats once daily for 10 days. Toxicity was induced by intraperitoneal injection of a single dose of cisplatin (7.5 mg/kg of body weight) on the 5th day of the experiment. Applied treatment with S. hortensis extract restored tissue morphology, ameliorated levels of serum parameters for liver, renal and testes function, tissue oxidative stress parameters, and increased Bcl-2/Bax ratio as an indicator of apoptosis in experimental animals caused by application of cisplatin. UHPLC/DAD/HESI-MS/MS analysis revealed that S. hortensis extract was rich in phenolic compounds with rosmarinic acid (24.9 mg/g) as the main compound, followed by caffeic acid (1.28 mg/g) and naringenin (1.06 mg/g). Our findings suggest that S. hortensis may be a valuable source of dietary and pharmacologically important phenolic compounds, especially rosmarinic acid, in pharmaceutical and functional food formulations in order to maintain normal health conditions or as a remedy in various diseases caused by oxidative damage.

The Beneficial Effects of Sulfur-containing Amino Acids on Cisplatininduced Cardiotoxicity and Neurotoxicity in Rodents.

BACKGROUND: Cisplatin is one the most frequently used chemotherapeutic drugs for several decades. Although its antineoplastic effect has been reported in treatment of numerous malignances, various adverse effects seem to be the crucial limiting factor for its administration. OBJECTIVE: Beside the most commonly described nephro- and hepatotoxicity, cisplatin therapy is also accompanied with gastrointestinal, reproductive, hematological, cardiovascular and neurological side effects. Since it has been reported that cisplatin induce oxidative damage in various tissues, it seems reasonable to investigate an antioxidant supplementation as potential therapeutical approach for attenuation of cisplatin toxicities. METHODS: We performed a structured search of bibliographic databases for research literature using a focused review question and inclusion/exclusion criteria. The quality of retrieved papers (101 in total) was appraised using standard tools. RESULTS: Numerous antioxidants (such as thiol compounds, polyphenols, vitamins, etc.) had been reported for their beneficial effects on cisplatin-induced cardiotoxicity. The effects of various antioxidants, including sulfur-containing amino acids, have also been explored for mitigation of cisplatin neurotoxicity. However, the results for antioxidant supplementation in reduction of cisplatin-induced toxicities are still to be applied in clinical trials. CONCLUSION: Considering the facts that sulfur-containing amino acids: (a) do not interfere with chemotherapeutics antitumor action; (b) do not exhibit any toxic effect (unless applied in dose several times above the recommended); and (c) produce significant protective effects on some cisplatin-induced toxicities connected to augmentation of oxidative damage - it seems that their administration can be harmless and protective supplementation against numerous adverse effects of certain antineoplastic agents.

The opposite effects of nandrolone decanoate and exercise on anxiety levels in rats may involve alterations in hippocampal parvalbumin-positive interneurons.

The aim of this study was to evaluate the behavioral effects of chronic (six weeks) nandrolone decanoate (ND, 20 mg/kg, s.c., weekly in single dose) administration (in order to mimic heavy human abuse), and exercise (swimming protocol of 60 minutes a day, five days in a row/two days break), applied alone and simultaneously with ND, in male rats (n = 40). Also, we evaluated the effects of those protocols on hippocampal parvalbumin (PV) content and the possible connection between the alterations in certain parts of hippocampal GABAergic system and behavioral patterns. Both ND and exercise protocols induced increase in testosterone, dihydrotestosterone and estradiol blood levels. Our results confirmed anxiogenic effects of ND observed in open field (OF) test (decrease in the locomotor activity, as well as in frequency and cumulative duration in the centre zone) and in elevated plus maze (EPM) test (decrease in frequency and cumulative duration in open arms, and total exploratory activity), that were accompanied with a mild decrease in the number of PV interneurons in hippocampus. Chronic exercise protocol induced significant increase in hippocampal PV neurons (dentate gyrus and CA1 region), followed by anxiolytic-like behavioral changes, observed in both OF and EPM (increase in all estimated parameters), and in evoked beam-walking test (increase in time to cross the beam), compared to ND treated animals. The applied dose of ND was sufficient to attenuate beneficial effects of exercise in rats by means of decreased exercise-induced anxiolytic effect, as well as to reverse exercise-induced augmentation in number of PV immunoreactive neurons in hippocampus. Our results implicate the possibility that alterations in hippocampal PV interneurons (i.e. GABAergic system) may be involved in modulation of anxiety level induced by ND abuse and/or extended exercise protocols.

The role of neuropeptide-Y in nandrolone decanoate-induced attenuation of antidepressant effect of exercise.

Since the increased prevalence of anabolic androgenic steroids abuse in last few decades is usually accompanied by various exercise protocols, the scope of our study was to evaluate the effects of chronic nandrolone decanoate administration in supraphysiological dose and a prolonged swimming protocol (alone and simultaneously with nandrolone decanoate) on depressive state in male rats. Simultaneously, we investigated the possible alterations in neuropeptide Y (NPY) content in blood and the hippocampus, in order to determine the role of NPY in the modulation of depressive-like behavior.Exercise induced antidepressant effects in tail suspension test (decrease of the total duration of immobility), as well as significant increase in the number of hippocampal NPY-interneurons in CA1 region. Chronic nandrolone decanoate treatment attenuated the beneficial antidepressant effects of exercise as measured by the tail suspension test parameters. Simultaneously, nandrolone decanoate treatment resulted in diminution of NPY content both in blood (decreased serum levels) and in hippocampus (the significant decrease in NPY expression in all three investigated hippocampal regions-CA1, CA2/3 and DG). Our findings indicate that alterations in serum and hippocampal NPY contents may underlie the changes in depressive state in rats. The exercise was beneficial as it exerted antidepressant effect, while chronic nandrolone decanoate treatment resulted in depressive-like behavior. Furthermore, the behavioral indicators of depression showed strong correlations with the serum levels and the hippocampal content of NPY.

Alterations of the oxidative status in rat hippocampus and prodepressant effect of chronic testosterone enanthate administration.

In a last few decades, anabolic-androgenic steroids (AASs) abuse has become serious health concern especially among adolescents. AASs abuse has been reported to be involved in pathogenesis of various mood disorders, including depression. In order to evaluate the effects of chronic (6 weeks) testosterone enanthate (TE) treatment in supraphysiological dose and exercise on depression-like behavior in rats, 32 male rats were divided into four groups: control (C), testosterone enanthate (T, 20 mg/kg/w, s.c.), exercise (E, swimming for 1 h/day), and combined group-testosterone enanthate plus exercise (T + E). TE produced prodepressant effect in tail suspension test (TST) parameters compared to the control and exercise groups, while exercise induced the opposite effect. Simultaneous TE administration along with exercise attenuated the antidepressant effect of exercise reversing the parameters of TST to the control values. Oxidative stress markers in rat hippocampus were significantly altered following applied protocols. TE administration increased index of lipid peroxidation (TBARS) and decreased superoxide dismutase activity (SOD), while exercise induced the opposite effect, with no change in glutathione (GSH) levels. Our results indicate that TE chronic treatment resulted in clear depressive-like behavior, even abolishing beneficial antidepressant effects of exercise in TST that was accompanied with increased oxidative damage in rat hippocampus. The antidepressant effect of exercise correlated with the improvement of redox status in hippocampal tissue. Behavioral parameters obtained in TST significantly correlated with the levels of oxidative stress markers.

In vitro and in vivo assessment of meadowsweet (Filipendula ulmaria) as anti-inflammatory agent.

ETHNOPHARMACOLOGICAL RELEVANCE: Meadowsweet (Filipendula ulmaria (L.) Maxim, Rosaceae) has been traditionally used in most European countries for the treatment of inflammatory diseases due to its antipyretic, analgesic, astringent, and anti-rheumatic properties. However, there is little scientific evidence on F. ulmaria anti-inflammatory effects regarding its impact on cyclooxygenases enzymatic activity and in vivo assessment of anti-inflammatory potential. This study aims to reveal the anti-inflammatory activity of methanolic extracts from the aerial parts (FUA) and roots (FUR) of F. ulmaria, both in in vitro and in vivo conditions. MATERIALS AND METHODS: The characteristic phenolic compounds in F. ulmaria extracts were monitored via high performance thin layer chromatography (HPTLC). The in vitro anti-inflammatory activity of F. ulmaria extracts was evaluated using cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) enzyme assays, and an assay for determining COX-2 gene expression. The in vivo anti-inflammatory effect of F. ulmaria extracts was determined in two doses (100 and 200 mg/kg b.w.) with hot plate test and carrageenan-induced paw edema test in rats. Inflammation was also evaluated by histopathological and immunohistochemical analysis. RESULTS: FUA extract showed the presence of rutoside, spiraeoside, and isoquercitrin. Both F. ulmaria extracts at a concentration of 50µg/mL were able to inhibit COX-1 and -2 enzyme activities, whereby FUA extract (62.84% and 46.43% inhibition, respectively) was double as effective as the root extract (32.11% and 20.20%, respectively). Extracts hardly inhibited the level of COX-2 gene expression in THP-1 cells at a concentration of 25µg/mL (10.19% inhibition by FUA and 8.54% by FUR). In the hot plate test, both extracts in two doses (100 and 200mg/kg b.w.), exhibited an increase in latency time when compared with the control group (p<0.05). In the carrageenan-induced acute inflammation test, FUA at doses of 100 and 200mg/kg b.w., and FUR at 200mg/kg, were able to significantly reduce the mean maximal swelling of rat paw until 6h of treatment. Indomethacin, FUA, and FUR extracts significantly decreased inflammation score and this effect was more pronounced after 24h, compared to the control group (p<0.05). CONCLUSIONS: The observed results of in vitro and, for the first time, in vivo anti-inflammatory activity of meadowsweet extracts, provide support of the traditional use of this plant in the treatment of different inflammatory conditions. Further investigation of the anti-inflammatory compounds could reveal the mechanism of anti-inflammatory action of these extracts.

The adverse effects of exercise and supraphysiological dose of testosterone-enanthate (TE) on exploratory activity in elevated plus maze (EPM) test - indications for using total exploratory activity (TEA) as a new parameter for ex.

OBJECTIVES: The aim of this study was the estimation of effects induced by chronic administration of supraphysiological dose of TE and prolonged exercise in male rats on anxiety levels (alterations in exploratory activity patterns in EPM). MATERIAL AND METHODS: Two sedentary (control - C and testosterone-enanthate - T) and two exercise (exercise - E and testosterone-enanthate plus exercise - T+E) groups (n=32) underwent adequate protocols - the swimming protocol (1 h/day) and TE (20 mg/kg/w, s.c.) for six weeks. Testing was performed in EPM. RESULTS: Anxiolytic effects of exercise were manifested as increased exploratory activity in EPM - increase in cumulative duration in open arms, the number of rearings and head-dippings, and TEA. Supraphysiological dose of TE decreased the number of rearings and head-dippings, cumulative duration in open arms and TEA compared to the control group, while this effect of TE was more pronounced compared to the exercise group. The applied dose of TE attenuated beneficial effects of exercise by means of all estimated parameters. CONSLUSIONS: Our results confirmed the beneficial effect of exercise on anxiety levels observed in EPM by means of parameters considering the alterations in exploratory activity. Supraphysiological dose of TE resulted in anxiogenic-like behavior in EPM. The effect of TE was so pronounced that the beneficial effect of exercise was reversed to the control values (or even below them). Based on the results of this trial, we propose that use of the TEA (a new parameter for overall exploratory activity) can improve the evaluation of EPM test results.

The effects of N-acetylcysteine on cisplatin-induced changes of cardiodynamic parameters within coronary autoregulation range in isolated rat hearts.

The aim of this study was to evaluate the effects of chronic NAC administration along with cisplatin on cisplatin-induced cardiotoxicity by means of coronary flow (CF), cardiodynamic parameters, oxidative stress markers and morphological changes in isolated rat heart. Isolated hearts of Wistar albino rats (divided into four groups: control, cisplatin, NAC and cisplatin+NAC group) were perfused according to Langendorff technique at constant coronary perfusion pressure starting at 50 and gradually increased to 65, 80, 95 and 110 cm H2O to evaluate cardiodynamic parameters within autoregulation range. Samples of coronary venous effluent (CVE) were collected for determination of CF and biochemical assays, and heart tissue samples for biochemical assays and histopathological examination. Cisplatin treatment decreased CF and heart rate, and increased left ventricular systolic pressure and maximum left ventricular pressure development rate. Cisplatin increased H2O2 and TBARS, but decreased NO2(-) levels in CVE. In tissue samples, cisplatin reduced pathological alterations in myocardium and coronary vessels, with no changes in the amount of total glutathione, as well as in activity of glutathione peroxidase and glutathione reductase. NAC coadministration, by reducing oxidative damage, attenuated cisplatin-induced changes of cardiodynamic and oxidative stress parameters, as well as morphological changes in myocardium and coronary vasculature.

The effects of N-acetylcysteine on cisplatin-induced cardiotoxicity on isolated rat hearts after short-term global ischemia.

The aim of this study was to estimate the protective effect of N-acetyl-l-cysteine (NAC) against cisplatin-induced cardiotoxicity under conditions of ischemic-reperfusion injury. Wistar albino rats were randomly divided into three groups (n = 8): control, cisplatin (5 mg/kg/w, i.p., 5 weeks) and cisplatin + NAC group (cisplatin - 5 mg/kg/w, i.p. and NAC - 500 mg/kg/w, i.p., 5 weeks). Isolated hearts were perfused according to the modified Langendorff technique at constant pressure (70 cmH2O). Following cardiodynamic parameters were measured: maximum rate of left ventricular pressure development, minimum rate of left ventricular pressure development, left ventricular systolic pressure (SLVP), left ventricular diastolic pressure and heart rate. The ischemic vasodilation episodes were induced by the complete interruption of coronary inflow for 30, 60 and 120 s. The samples of the coronary venous effluent (CVE) were continuously collected during the reperfusion period for determination of coronary flow (CF) rate and oxidative stress markers (H2O2, O2-, NO2- and thiobarbituric acid reactive substances - TBARS). Cisplatin reduced CF, heart rate and overflow (total, maximal and duration of overflow) during reperfusion, and increased SLVP (under basal conditions and after global ischemias). Cisplatin increased levels of H2O2 (under basal conditions), O2- and TBARS (under basal conditions and after ischemia), but decreased NO2- levels (during reperfusion) in CVE, and decreased superoxide dismutase and reduced glutathione in serum. NAC attenuated cisplatin-induced changes of cardiodynamic parameters (except CF under basal conditions) and oxidative stress parameters. Those results suggest that NAC, by decreasing oxidative stress, may be useful in cardioprotection during cisplatin therapy.

Anxiogenic effects of chronic exposure to nandrolone decanoate (ND) at supraphysiological dose in rats: a brief report.

OBJECTIVE: Nandrolone decanoate (ND) is frequently used anabolic androgenic steroid (AAS) among the athletes. Despite the health risks, there is significant increase in prevalence of AAS abuse. DESIGN: The aim of this study was to investigate the effects of chronic exposure to ND at supraphysiological dose (to mimic the doses for human AAS abusers) on anxiety levels in adult rats. SETTINGS: We performed several behavioral tests (open field test, elevated plus maze test, beam-walking test, evoked beam-walking test and tail suspension test) for estimation of anxiety in rats. Adult rats received 20 mg/kg intraperitoneal injection of ND weekly for four weeks. Behavioral test were performed on the seventh day after the last dose of ND. RESULTS: Anxiogenic-like pattern of behavior was clearly observed in several behavioral tests, such as open field test (decrease of total distance moved and cumulative duration of moving, decrease of an average velocity of the animals, decrease of frequency and total time in centre zone); elevated plus maze (decreased total time spent in open arms and the number of entries in open arms of the elevated plus maze); evoked beam-walking test (decreased time to cross the beam) and tail suspension test (increased latency to first immobility and decreased total duration of immobility). MAIN FINDINGS: Results of this study show that four-week treatment with the supraphysiological dose of ND produced anxiogenic effects in sedentary male rats. CONCLUSION: Our results show that rats after chronic treatment with a supraphysiological dose of ND exhibited anxiety-like behavior.

Effects of DL-homocysteine thiolactone on cardiac contractility, coronary flow, and oxidative stress markers in the isolated rat heart: the role of different gasotransmitters.

Considering the adverse effects of DL-homocysteine thiolactone hydrochloride (DL-Hcy TLHC) on vascular function and the possible role of oxidative stress in these mechanisms, the aim of this study was to assess the influence of DL-Hcy TLHC alone and in combination with specific inhibitors of important gasotransmitters, such as L-NAME, DL-PAG, and PPR IX, on cardiac contractility, coronary flow, and oxidative stress markers in an isolated rat heart. The hearts were retrogradely perfused according to the Langendorff technique at a 70 cm H2O and administered 10 µM DL-Hcy TLHC alone or in combination with 30 µM L-NAME, 10 µM DL-PAG, or 10 µM PPR IX. The following parameters were measured: dp/dt max, dp/dt min, SLVP, DLVP, MBP, HR, and CF. Oxidative stress markers were measured spectrophotometrically in coronary effluent through TBARS, NO2, O2(-), and H2O2 concentrations. The administration of DL-Hcy TLHC alone decreased dp/dt max, SLVP, and CF but did not change any oxidative stress parameters. DL-Hcy TLHC with L-NAME decreased CF, O2(-), H2O2, and TBARS. The administration of DL-Hcy TLHC with DL-PAG significantly increased dp/dt max but decreased DLVP, CF, and TBARS. Administration of DL-Hcy TLHC with PPR IX caused a decrease in dp/dt max, SLVP, HR, CF, and TBARS.

The effects of cyclooxygenase and nitric oxide synthase inhibition on oxidative stress in isolated rat heart.

Despite the widespread clinical use of cyclooxygenase (COX) inhibitors, dilemmas still exist about potential impact of these drugs on cardiovascular system. The present study was aimed to estimate the effects of different COX inhibitors (meloxicam, acetylsalicylic acid [ASA], and SC-560) on oxidative stress in isolated rat heart, with special focus on L-arginine/NO system. The hearts of male Wistar albino rats (total number n = 96, each group 12 rats, 8 weeks old, body mass 180-200 g) were retrogradely perfused according to the Langendorff technique at gradually increased perfusion pressure (40-120 cmH2O). After control experiments the hearts were perfused with the following drugs: 100 µmol/l ASA (Aspirin), alone or in combination with 30 µmol/l L-NAME, 0.3 µmol/l meloxicam (movalis) with or without 30 µmol/l L-NAME, 3 µmol/l meloxicam (alone or in combination with 30 µmol/l L-NAME), 30 µmol/l L-NAME, and administration of 0.25 µmol/l SC-560. In samples of coronary venous effluent the following oxidative stress markers were measured spectrophotometrically: index of lipid peroxidation (measured as thiobarbituric acid reactive substances [TBARS]), superoxide anion radical release (O2(-)), and hydrogen peroxide (H2O2). While ASA was found to have an adverse influence on redox balance in coronary circulation, and coronary perfusion, meloxicam and SC-560 do not negatively affect the intact model of the heart. Furthermore, all effects were modulated by NOS inhibition. It seems that interaction between COX and L-arginine/NO system truly exists in coronary circulation, and can be one of the possible causes for achieved effects. That means: those effects induced by different inhibitors of COX are modulated by subsequent inhibition of NOS.