RESUMO
The betta (Betta splendens) is a carnivorous ornamental species that requires live food. In this study, we evaluated the growth and survival of Betta splendens fingerlings fed ex-situ biofloc (BFT). A total of 375 fingerlings (8.3 ± 4.1 mg and 0.8 ± 0.14 cm) were distributed into 15-L plastic tanks (n=25), with five replicates for each of the following treatments: (i) exclusive live food (LF100), (ii) exclusive biofloc (BFT100), (iii) live food supplemented with biofloc (LF100-BFT100), and a reduction of 15% (iv) and 30% (v) in live food with biofloc supplementation (LF85-BFT100 and LF70-BFT100, respectively). The fish were fed newly hatched brine shrimp (Artemia spp. nauplii) and/or fresh biofloc, twice daily, over a 16-day experimental period. Dietary supplementation of Beta splendens with ex-situ BFT (LF100-BFT100, LF85-BFT100, and LF70-BFT100) resulted in a similar final weight (P>0.05) compared to exclusive brine shrimp (LF100). Regarding total length, the fish in the LF100-BFT100 group were superior to those in the LF100 group (P<0.05). The LF100 and LF100-BFT100 groups showed survival rates of 100% and 98.4%, respectively, which were not statistically different (P>0.05). For all analyzed variables, fish exclusively fed biofloc (BFT100) exhibited unfavorable performance. These results indicate that dietary ex-situ biofloc supplementation, without reducing the supply of live food, can be an interesting alternative in the rearing of Betta splendens since biofloc improves growth performance and maintains a good survival rate.
Assuntos
Ração Animal , Animais , Aquicultura/métodos , ArtemiaRESUMO
The objective of this study was to evaluate reproductive traits in adults of Astyanax lacustris subjected to different spawning inducers. The study involved 240 females (12.54 g ± 2.33 and 7.66 cm ± 0.63 cm) and 240 males (5.83 g ± 0.39 g and 6.14 cm ± 0.64 cm), all at reproductive age. Three different inducers were evaluated: (i) 0.4 pellets of Ovopel®/kg of body weight; (ii) 0.5 ml of buserelin acetate/kg of body weight; and (iii) carp pituitary extract (CPE) (5.5 mg CPE/kg body weight for females and 2.5 mg CPE/kg body weight for males), as well as saline solution (without hormone). The degree-hours for spawning were greater (P<0.05) for the Ovopel® treatment (with 204.93) than in the treatment with CPE (183.2). Ovary weight and gonadosomatic index were higher (P<0.05) in CPE and Ovopel® treatments when compared to buserelin acetate. The number of oocytes per female, absolute and relative fecundity were greater (P<0.05) for Ovopel® and CPE treatments. Fertilization rate was higher (P<0.05) in treatment with buserelin acetate (82.3%) in relation to Ovopel® (72.33%) and CPE (62.40%) treatments, and the highest (P<0.05) hatching rates were achieved with buserelin acetate and Ovopel®. The number of larvae per female body weight was greater (P<0.05) when Ovopel® was used. In conclusion, Ovopel® proves to be a more effective reproductive inducer for induced reproduction of A. lacustris when compared to CPE and buserelin acetate.
Assuntos
Carpas , Characidae , Masculino , Animais , Feminino , Busserrelina/farmacologia , Reprodução , Peso CorporalRESUMO
The recently described 'gasomediator' hydrogen sulfide (H2S) has been involved in pain mechanisms, but its effect on pruritus, a sensory modality that similarly to pain acts as a protective mechanism, is poorly known and controversial. The effects of the slow-releasing (GYY4137) and spontaneous H2S donors (Na2S and Lawesson's reagent, LR) were evaluated in histamine and compound 48/80 (C48/80)-dependent dorsal skin pruritus and inflammation in male BALB/c mice. Animals were intradermally (i.d.) injected with C48/80 (3µg/site) or histamine (1µmol/site) alone or co-injected with Na2S, LR or GYY4137 (within the 0.3-100nmol range). The involvement of endogenous H2S and KATP channel-dependent mechanism were also evaluated. Pruritus was assessed by the number of scratching bouts, whilst skin inflammation was evaluated by the extravascular accumulation of intravenously injected 125I-albumin (plasma extravasation) and myeloperoxidase (MPO) activity (neutrophil recruitment). Histamine or C48/80 significantly evoked itching behavior paralleled by plasma extravasation and increased MPO activity. Na2S and LR significantly ameliorated histamine or C48/80-induced pruritus and inflammation, although these effects were less pronounced or absent with GYY4137. Inhibition of endogenous H2S synthesis increased both Tyrode and C48/80-induced responses in the skin, whereas the blockade of KATP channels by glibenclamide did not. H2S-releasing donors significantly attenuate C48/80-induced mast cell degranulation either in vivo or in vitro. We provide first evidences that H2S donors confer protective effect against histamine-mediated acute pruritus and cutaneous inflammation. These effects can be mediated, at least in part, by stabilizing mast cells, known to contain multiple mediators and to be primary initiators of allergic processes, thus making of H2S donors a potential alternative/complementary therapy for treating inflammatory allergic skin diseases and related pruritus.
Assuntos
Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Inflamação/tratamento farmacológico , Mastócitos/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Prurido/tratamento farmacológico , Pele/efeitos dos fármacos , Animais , Glibureto/farmacologia , Histamina/metabolismo , Inflamação/metabolismo , Canais KATP/metabolismo , Masculino , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Morfolinas/farmacologia , Compostos Organotiofosforados/farmacologia , Prurido/metabolismo , Pele/metabolismoRESUMO
Hydrogen sulfide (H2S) has been highlighted as an endogenous signaling molecule and we have previously found that it can inhibit histamine-mediated itching. Pruritus is the most common symptom of cutaneous diseases and anti-histamines are the usual treatment; however, anti-histamine-resistant pruritus is common in some clinical settings. In this way, the involvement of mediators other than histamine in the context of pruritus requires new therapeutic targets. Considering that the activation of proteinase-activated receptor 2 (PAR-2) is involved in pruritus both in rodents and humans, in this study we investigated the effect of H2S donors on the acute scratching behavior mediated by PAR-2 activation in mice, as well as some of the possible pharmacological mechanisms involved. The intradermal injection of the PAR-2 peptide agonist SLIGRL-NH2 (8-80nmol) caused a dose-dependent scratching that was unaffected by intraperitoneal pre-treatment with the histamine H1 antagonist pyrilamine (30mg/kg). Co-injection of SLIGRL-NH2 (40nmol) with either the slow-release H2S donor GYY4137 (1 and 3nmol) or the spontaneous donor NaHS (1 and 0.3nmol) significantly reduced pruritus. Co-treatment with the KATP channel blocker glibenclamide (200nmol) or the nitric oxide (NO) donor sodium nitroprusside (10nmol) abolished the antipruritic effects of NaHS; however, the specific soluble guanylyl cyclase inhibitor ODQ (30µg) had no significant effects. The transient receptor potential ankyrin type 1 (TRPA1) antagonist HC-030031 (20µg) significantly reduced SLIGRL-NH2-induced pruritus; however pruritus induced by the TRPA1 agonist AITC (1000nmol) was unaffected by NaHS. Based on these data, we conclude that pruritus secondary to PAR-2 activation can be reduced by H2S, which acts through KATP channel opening and involves NO in a cyclic guanosine monophosphate (cGMP)-independent manner. Furthermore, TRPA1 receptors mediate the pruritus induced by activation of PAR-2, but H2S does not interfere with this pathway. These results provide additional support for the development of new therapeutical alternatives, mainly intended for treatment of pruritus in patients unresponsive to anti-histamines.
Assuntos
Sulfeto de Hidrogênio/farmacologia , Oligopeptídeos/farmacologia , Prurido/tratamento farmacológico , Receptor PAR-2/metabolismo , Animais , Modelos Animais de Doenças , Glibureto/farmacocinética , Histamina/metabolismo , Antagonistas dos Receptores Histamínicos/farmacologia , Isotiocianatos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Morfolinas/farmacologia , Nitroprussiato/farmacologia , Compostos Organotiofosforados/farmacologia , Prurido/metabolismo , Canais de Potencial de Receptor Transitório/metabolismoRESUMO
Leishmania spp are the causative agents of a spectrum of diseases termed leishmaniasis that affect mammals, including humans and dogs. Although reactive nitrogen species are employed in the control of parasitism by the immune system, it is known that Leishmania can withstand this oxidative stress. As the mechanism by which these species are resistant to nitric oxide (NO) is poorly understood, the main objective of this study was to evaluate the expression of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in Leishmania amazonensis and Leishmania chagasi promastigotes showing natural resistance to NO. GAPDH transcript levels were quantified by real-time polymerase chain reaction amplification, and GAPDH activity (assessed by levels of NADH oxidation) was measured by spectrophotometry. The level of nitration in total protein was assessed by immunoblotting. The results demonstrated an increase in GAPDH expression in resistant isolates of both species compared to susceptible isolates. The increase in GAPDH expression led to an increase in the activity of GAPDH in L. amazonensis human isolates resistant to NO. The pattern of protein nitration did not differ between sensitive and resistant isolates. Our results suggest that changes in expression of GAPDH may be responsible, at least in part, to natural resistance to NO found in human and canine Leishmania spp.
Assuntos
Expressão Gênica/efeitos dos fármacos , Gliceraldeído 3-Fosfato Desidrogenase (NADP+)/genética , Leishmania infantum/genética , Leishmania/genética , Estágios do Ciclo de Vida/efeitos dos fármacos , Óxido Nítrico/farmacologia , Proteínas de Protozoários/genética , Meios de Cultura , Resistência a Medicamentos , Gliceraldeído 3-Fosfato Desidrogenase (NADP+)/metabolismo , Leishmania/efeitos dos fármacos , Leishmania/enzimologia , Leishmania/crescimento & desenvolvimento , Leishmania infantum/efeitos dos fármacos , Leishmania infantum/enzimologia , Leishmania infantum/crescimento & desenvolvimento , NAD/metabolismo , Óxido Nítrico/metabolismo , Oxirredução , Proteínas de Protozoários/metabolismo , Nitrito de Sódio/química , Nitrito de Sódio/farmacologiaRESUMO
BACKGROUND: Nitric oxide is a key signalling molecule in the pathogenesis of inflammation, but its role in acute pancreatitis and related abdominal pain induced by secretory phospholipase A2 (sPLA2 ) from Crotalus durissus terrificus (Cdt) venom has not been investigated. METHODS: Male Wistar rats were i.v. injected with L-NAME (20 mg/kg), aminoguanidine (AG, 50 mg/kg), 7-nitroindazole (7-NI, 10 mg/kg) or vehicle 10 min before or 60 min after the injection of sPLA2 (300 µg/kg) into the common bile duct. After 4 h of sPLA2 injection, abdominal hyperalgesia and inflammation were assessed in addition to serum amylase, nitrite/nitrate (NOx), pancreas lipoperoxidation and 3-nitrotyrosine (3-NT) contents. RESULTS: sPLA2 -induced acute pancreatitis, related abdominal hyperalgesia, hyperamylasemia and increased concentration of NOx were not correlated with lipoperoxidation or increased 3-NT in the pancreas. Pretreatment with all the nitric oxide synthase (NOS) inhibitors significantly reduced abdominal mechanical hyperalgesia, but only iNOS blockade by AG suppressed pancreas oedema and serum NOx increase. The therapeutic approach with all the NOS inhibitors produced a similar reduction pattern of the abdominal hyperalgesia, but AG treatment also inhibited serum hyperamylasemia and NOx concentrations and pancreatic myeloperoxidase. The nNOS blockade by 7-NI treatment also inhibited myeloperoxidase activity in both pancreas and lung. CONCLUSIONS: Therapeutic blockade of iNOS or nNOS provides benefits in terms of inhibition of the acute pancreatitis-related abdominal hyperalgesia, while iNOS inhibition also ameliorates the inflammatory cell influx to the pancreas and reduces the resultant hyperamylasemia and NOx levels, thus representing alternative pharmacological strategies for treatment of clinical pancreatitis associated with increased PLA2 .
Assuntos
Inibidores Enzimáticos/uso terapêutico , NG-Nitroarginina Metil Éster/uso terapêutico , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Dor/tratamento farmacológico , Dor/etiologia , Pancreatite/complicações , Pancreatite/tratamento farmacológico , Fosfolipases A2 Secretórias , Animais , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Masculino , Pâncreas/enzimologia , Pâncreas/patologia , Pancreatite/enzimologia , Peroxidase/metabolismo , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismoRESUMO
We have shown previously that nitric oxide (NO) controls platelet endothelial cell adhesion molecule (PECAM-1) expression on both neutrophils and endothelial cells under physiological conditions. Here, the molecular mechanism by which NO regulates lipopolysaccharide (LPS)-induced endothelial PECAM-1 expression and the role of interleukin (IL)-10 on this control was investigated. For this purpose, N-(G)-nitro-L-arginine methyl ester (L-NAME; 20 mg/kg/day for 14 days dissolved in drinking water) was used to inhibit both constitutive (cNOS) and inducible nitric oxide (iNOS) synthase activities in LPS-stimulated Wistar rats (5 mg/kg, intraperitoneally). This treatment resulted in reduced levels of serum NO. Under this condition, circulating levels of IL-10 was enhanced, secreted mainly by circulating lymphocytes, dependent on transcriptional activation, and endothelial PECAM-1 expression was reduced independently on reduced gene synthesis. The connection between NO, IL-10 and PECAM-1 expression was examined by incubating LPS-stimulated (1 µg/ml) cultured endothelial cells obtained from naive rats with supernatant of LPS-stimulated lymphocytes, which were obtained from blood of control or L-NAME-treated rats. Supernatant of LPS-stimulated lymphocytes obtained from L-NAME-treated rats, which contained higher levels of IL-10, reduced LPS-induced PECAM-1 expression by endothelial cells, and this reduction was reversed by adding the anti-IL-10 monoclonal antibody. Therefore, an association between NO, IL-10 and PECAM-1 was found and may represent a novel mechanism by which NO controls endothelial cell functions.
Assuntos
Inflamação/metabolismo , Interleucina-10/metabolismo , Lipopolissacarídeos/imunologia , Linfócitos/metabolismo , Óxido Nítrico/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Animais , Anticorpos Monoclonais , Células Cultivadas , Células Endoteliais/metabolismo , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Inflamação/imunologia , Interleucina-10/sangue , Interleucina-10/imunologia , NG-Nitroarginina Metil Éster/administração & dosagem , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND AND PURPOSE: Recent findings suggest that the noxious gas H(2)S is produced endogenously, and that physiological concentrations of H(2)S are able to modulate pain and inflammation in rodents. This study was undertaken to evaluate the ability of endogenous and exogenous H(2)S to modulate carrageenan-induced synovitis in the rat knee. EXPERIMENTAL APPROACH: Synovitis was induced in Wistar rats by intra-articular injection of carrageenan into the knee joint. Sixty minutes prior to carrageenan injection, the rats were pretreated with indomethacin, an inhibitor of H(2)S formation (DL-propargylglycine) or an H(2)S donor [Lawesson's reagent (LR)]. KEY RESULTS: Injection of carrageenan evoked knee inflammation, pain as characterized by impaired gait, secondary tactile allodynia of the ipsilateral hindpaw, joint swelling, histological changes, inflammatory cell infiltration, increased synovial myeloperoxidase, protein nitrotyrosine residues, inducible NOS (iNOS) activity and NO production. Pretreatment with LR or indomethacin significantly attenuated the pain responses, and all the inflammatory and biochemical changes, except for the increased iNOS activity, NO production and 3-NT. Propargylglycine pretreatment potentiated synovial iNOS activity (and NO production), and enhanced macrophage infiltration, but had no effect on other inflammatory parameters. CONCLUSIONS AND IMPLICATIONS: Whereas exogenous H(2)S delivered to the knee joint can produce a significant anti-inflammatory and anti-nociceptive effect, locally produced H(2)S exerts little immunomodulatory effect. These data further support the development and use of H(2)S donors as potential alternatives (or complementary therapies) to the available anti-inflammatory compounds used for treatment of joint inflammation or relief of its symptoms.
Assuntos
Carragenina/efeitos adversos , Sulfeto de Hidrogênio/farmacologia , Articulação do Joelho/patologia , Sinovite/induzido quimicamente , Animais , Articulação do Joelho/enzimologia , Articulação do Joelho/metabolismo , Masculino , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Peroxidase/metabolismo , Ratos , Ratos Wistar , Sinovite/enzimologia , Sinovite/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismoRESUMO
BACKGROUND AND PURPOSE: Overactive bladder is a complex and widely prevalent condition, but little is known about its physiopathology. We have carried out morphological, biochemical and functional assays to investigate the effects of long-term nitric oxide (NO) deficiency on muscarinic receptor and beta-adrenoceptor modulation leading to overactivity of rat detrusor muscle. EXPERIMENTAL APPROACH: Male Wistar rats received N(omega)-nitro-L-arginine methyl ester (L-NAME) in drinking water for 7-30 days. Functional responses to muscarinic and beta-adrenoceptor agonists were measured in detrusor smooth muscle (DSM) strips in Krebs-Henseleit solution. Measurements of [(3)H]inositol phosphate, NO synthase (NOS) activity, [(3)H]quinuclidinyl benzilate ([(3)H]QNB) binding and bladder morphology were also performed. KEY RESULTS: Long-term L-NAME treatment significantly increased carbachol-induced DSM contractile responses after 15 and 30 days; relaxing responses to the beta(3)-adrenoceptor agonist BRL 37-344 were significantly reduced at 30 days. Constitutive NOS activity in bladder was reduced by 86% after 7 days and maintained up to 30 days of L-NAME treatment. Carbachol increased sixfold the [(3)H]inositol phosphate in bladder tissue from rats treated with L-NAME. [(3)H]QNB was bound with an apparent K(D) twofold higher in bladder membranes after L-NAME treatment compared with that in control. No morphological alterations in DSM were found. CONCLUSIONS AND IMPLICATIONS: Long-term NO deficiency increased rat DSM contractile responses to a muscarinic agonist, accompanied by significantly enhanced K(D) values for muscarinic receptors and [(3)H]inositol phosphate accumulation in bladder. This supersensitivity for muscarinic agonists along with reductions of beta(3)-adrenoceptor-mediated relaxations indicated that overactive DSM resulted from chronic NO deficiency.
Assuntos
Contração Muscular/efeitos dos fármacos , Óxido Nítrico/deficiência , Receptores Adrenérgicos beta 3/metabolismo , Receptores Muscarínicos/metabolismo , Bexiga Urinária Hiperativa/fisiopatologia , Agonistas de Receptores Adrenérgicos beta 3 , Agonistas Adrenérgicos beta/farmacologia , Animais , Carbacol/farmacologia , Fosfatos de Inositol/metabolismo , Masculino , Agonistas Muscarínicos/farmacologia , Músculo Liso/metabolismo , NG-Nitroarginina Metil Éster , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Wistar , Receptores Muscarínicos/efeitos dos fármacos , Bexiga Urinária/metabolismo , Bexiga Urinária/fisiopatologiaRESUMO
We have previously reported that in comparison with normal rats, the presence of experimental allergic encephalomyelitis (EAE) leads to decreased endogenous inhibitory activity (EIA) of Ca2+-dependent nitric oxide synthase (NOS) in both brain and serum, and increased expression of protein 3-nitrotyrosine (NT) in brain. In this work we show that animals recovered from the clinical signs of EAE are not different from controls in terms of either brain NOS activity, EIA of NOS, or NT expression. These results suggest that parallel to the reversal of the disease symptoms, a normalization of the production of nitric oxide and related species occurs.