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1.
Anim Microbiome ; 6(1): 51, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289751

RESUMO

Fish health, growth and disease is intricately linked to its associated microbiome. Understanding the influence, source and ultimately managing the microbiome, particularly for vulnerable early life-stages, has been identified as one of the key requirements to improving farmed fish production. One tropical fish species of aquaculture importance farmed throughout the Asia-Pacific region is the giant grouper (Epinephelus lanceolatus). Variability in the health and survival of E. lanceolatus larvae is partially dependent on exposure to and development of its early microbiome. Here, we examined the development in the microbiome of commercially reared giant grouper larvae, its surrounding environment, and that from live food sources to understand the type of bacterial species larvae are exposed to, and where some of the sources of bacteria may originate. We show that species richness and microbial diversity of the larval microbiome significantly increased in the first 4 days after hatching, with the community composition continuing to shift over the initial 10 days in the hatchery facility. The dominant larval bacterial taxa appeared to be predominantly derived from live cultured microalgae and rotifer feeds and included Marixanthomonas, Candidatus Hepatincola, Meridianimaribacter and Vibrio. In contrast, a commercial probiotic added as part of the hatchery's operating procedure failed to establish in the larvae microbiome. Microbial source tracking indicated that feed was the largest influence on the composition of the giant grouper larvae microbiome (up to 55.9%), supporting attempts to modulate fish microbiomes in commercial hatcheries through improved diets. The marked abundances of Vibrio (up to 21.7% of 16S rRNA gene copies in larvae) highlights a need for rigorous quality control of feed material.

2.
J Plast Reconstr Aesthet Surg ; 69(9): 1184-91, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27406255

RESUMO

BACKGROUND: Patient-reported outcomes and quality of life following mastectomy are not well understood. This study evaluates the quality of life following surgery for breast cancer and compares outcomes following breast-conserving surgery versus total mastectomy with or without reconstruction. METHODS: A case-controlled cross-sectional study was conducted using the validated BREAST-Q™ questionnaire and a study-specific questionnaire to determine patient's views about surgical outcomes. Questionnaires were completed by patients following breast-conserving surgery and total mastectomy with or without reconstruction and by controls without breast cancer. A one-way ANOVA was used to compare mean BREAST-Q™ scores between groups and post hoc analysis using Tukey's and Kruskal-Wallis tests. RESULTS: BREAST-Q™ questionnaires were completed by 400 women (123 controls, 97 breast conservations, 93 mastectomies without reconstruction, 87 mastectomies with reconstruction). Women who had undergone mastectomy and reconstruction had higher scores in satisfaction with breast and sexual well-being domains compared with women who had breast-conserving surgery, and women who had total mastectomy without reconstruction had the lowest scores in these two domains. There was no difference in psychosocial well-being between the groups. Women who had undergone breast-conserving surgery scored the lowest in the physical well-being chest domain and the majority reported breast asymmetry. CONCLUSION: Our study suggests that women who undergo total mastectomy and breast reconstruction for cancer achieve a quality-of-life outcome that is at least as good as that following breast-conserving surgery. Furthermore, breast conservation has been found to be associated with lower physical well-being (i.e., more pain and discomfort) in the chest area and poorer sexual well-being outcomes.


Assuntos
Neoplasias da Mama/cirurgia , Mamoplastia/psicologia , Mastectomia/psicologia , Satisfação do Paciente , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
3.
ANZ J Surg ; 86(12): 1038-1041, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26510720

RESUMO

BACKGROUND: The central venous access port device (CVAPD) provides reliable vascular access and is used for delivery of fluids and for obtaining blood samples. However, it can carry some intra- and post-operative complications such as thrombosis, pneumothorax, catheter fracture and port malposition. This article describes one surgeon's experience over a 16-year period and strategies to avoid complications. METHODS: The data were prospectively collected from 1996 to 2012 (16-year period). Collected data included age and gender of the patient, pathology, type of port used, anaesthetic type, side and site of insertion, and complications. RESULTS: A total of 958 devices were implanted. The average age of the patient was 57.8 years. Sixty-eight complications were recorded with an average complication rate of 7.1%. This rate decreased from 23% between 1996 and 1997 to 3.6% from 2010 to 2013. Venous thrombosis was the main source of complications with an incidence of 2.5%. This complication occurred in seven of the first 86 patients (8.1%, 1996-1998) and decreased to 1.9% between 2000 and 2013. Twenty infections (2%), five pneumothoraces secondary to insertion (0.5%), one port malposition (0.1%) and three fractures of the catheter (0.3%) occurred over the 16 years. CONCLUSION: The surgeon's complications of CVAPD insertion requiring removal or revision of the port were considerably reduced as the surgeon's experience increases. It is suggested that all surgeons whose practice includes CVAPD insertion will have an initial learning curve, and strategies described in this paper may help decrease the number of complications.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Cateteres de Demora/efeitos adversos , Trombose Venosa/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Curva de Aprendizado , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Austrália do Sul/epidemiologia , Trombose Venosa/etiologia
4.
Gen Comp Endocrinol ; 179(2): 221-31, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22940647

RESUMO

In non-mammalian vertebrates, the nonapeptide arginine-vasotocin (AVT) is involved in the regulation of social behavior related to reproduction and aggression. The cichlid fish Cichlasoma dimerus is a monogamous species with complex social hierarchies. Males are found in one of two basic alternative phenotypes: Non-territorial and territorial males. In this work we characterize the vasotocinergic system in males of C. dimerus in relation to social status with particular emphasis on the various putative sites of action of AVT across the hypothalamic-pituitary-gonad (HPG) axis, and its effects on reproductive and social behavior. The location and distribution of vasotocinergic neurons in the brain was studied, highlighting a morphometric analysis of AVT producing neurons in males of different social status. The effect of AVT on pituitary gonadotropin secretion was analyzed by single pituitary culture while expression of AVT in peripheral organs was studied by RT-PCR using specific primers. Finally, the role of AVT on testicular androgen release was assessed by in vitro incubation of testis. Results showed a positive effect of AVT on gonadotropin secretion, where ß-LH showcased a triphasic response under increasing AVT concentration, while ß-FSH's response was dose-dependent and directly proportional. AVT showed a positive and concentration-dependent effect over testicular androgens synthesis and secretion in vitro. Vasotocin expression was observed in testicular somatic tissue located in the interstitial compartment. Thus, the AVT system in C. dimerus appears to be of high complexity, with multiple sites of action in the hypothalamus-pituitary-gonadal axis.


Assuntos
Ciclídeos/fisiologia , Comportamento Sexual Animal/fisiologia , Vasotocina/fisiologia , Androgênios/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Neurônios/metabolismo , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Social , Predomínio Social , Territorialidade , Testículo/metabolismo , Vasotocina/biossíntese
5.
Gen Comp Endocrinol ; 176(1): 52-61, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22226730

RESUMO

Somatolactin (SL) and SL receptor (SLR) belong to the growth hormone and cytokine type I receptor superfamilies, respectively. However, further research is required to define the duplications and functions of SL and its receptors in basal vertebrates including environmental background color adaptation in fish. In the present study, we cloned and sequenced SL and its putative receptor (SLR), classified and compared the sequences phylogenetically, and determined SL and SLR mRNA expression levels during long-term background color exposure in Cichlasoma dimerus, a freshwater South American cichlid. Our results show that C. dimerus SL and SLR share high sequence similarity with homologous from other perciform fish. Phylogenetic analysis indicates that C. dimerus SL belongs to the SLα clade sub-group. C. dimerus SLR is clearly a member of the GHR1 receptor subgroup, which includes the experimentally validated SLR from salmonids. Higher transcript levels of SLα in the pituitary and SLR in the epidermis and dermis cells of fish scales were observed in fish following long-term black background color exposure compared to those exposed to a white background. A higher number of melanophores was also observed in fish exposed for 10days to a black background compared to those exposed to a white background. These changes were concomitant to differences in SL or SLR transcript levels found in fish exposed to these two different background colors. Our results suggest, for the first time, that SLR is expressed in fish scales, and that there is an increase in SL in the pituitary and the putative SLR in likely target cells, i.e., melanophores, in long-term black background exposure in C. dimerus.


Assuntos
Aclimatação/genética , Ciclídeos/genética , Proteínas de Peixes/genética , Glicoproteínas/genética , Hormônios Hipofisários/genética , Receptores do Hormônio Hipofisário/genética , Receptores da Somatotropina/genética , Pigmentação da Pele/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Ciclídeos/fisiologia , Clonagem Molecular , Cor , Meio Ambiente , Proteínas de Peixes/fisiologia , Glicoproteínas/fisiologia , Melanóforos/fisiologia , Dados de Sequência Molecular , Filogenia , Hormônios Hipofisários/fisiologia , RNA Mensageiro/metabolismo , Receptores do Hormônio Hipofisário/fisiologia , Receptores da Somatotropina/fisiologia
6.
Neotrop. ichthyol ; 9(3): 559-570, 2011. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-600879

RESUMO

In this work we describe for the first time the social and reproductive behavior of the Neotropical fish Cichlasoma dimerus (Heckel, 1840) [Perciformes: Cichlidae], endemic to the Paraná River basin, using a comprehensive-integral approach, including morphological and physiological features. This substrate breeding fish has biparental care of the fry and presents a dominance hierarchy that determines access to breeding territories among males, and to males with territories among females. Gregarious behavior associated with a pale body color, was observed before reproductive behaviors started. Afterwards, a dominance hierarchy was established through aggressive interactions. Territorial individuals had bright body color patterns and non territorial an opaque grey one. Black ventral coloration was associated with reproductive individuals. Courtship displays, which were similar to threatening displays, had the common effect of increasing the visible area of the individual. The dominant male was always the largest one suggesting that size is probably a major factor determining the hierarchy establishment and that these intra-sexually selected traits may have been reinforced by inter-sexual selection. Reproductive males had higher pituitary levels of β-follicle stimulating hormone (β-FSH) and somatolactin (SL) than non reproductive ones, while no differences were found among females. No differences were found among male gonadosomatic indexes. Non reproductive individuals had higher plasma cortisol levels for both sexes. It is possible that dominant reproductive individuals may be inhibiting reproduction of subordinate fish through physical contact, increasing their cortisol levels and diminishing FSH and SL pituitary content. However, this was not reflected as an inhibition at the gonadal level in our experimental design.


En este trabajo se describen por primera vez el comportamiento social y reproductivo del pez cíclido neotropical Cichlasoma dimerus (Heckel, 1840) [Perciformes: Cichlidae], endémico de la cuenca del Paraná, desde un enfoque integral y abarcador, incluyendo características morfológicas y fisiológicas. Éste pez incubador de substrato, tiene cuidado biparental de las crías y presenta una jerarquía de dominancia que determina el acceso a territorios reproductivos entre los machos, y a machos con territorios entre las hembras. Se observó un comportamiento gregario con una coloración corporal pálida característica, antes que comenzaran los comportamientos reproductivos. Luego, una jerarquía de dominancia se estableció a través de interacciones agresivas. Los individuos territoriales presentaron patrones de coloración corporal brillantes y los individuos no territoriales uno gris opaco. Una coloración ventral oscura fue observada asociada a individuos reproductivos. Los despliegues de cortejo fueron similares a los de amenaza y tuvieron la característica común de aumentar el área visible de los peces. El macho dominante fue siempre el más grande, sugiriendo que probablemente la fuerza (tamaño) es un factor preponderante determinando el establecimiento de las jerarquías y que éstas características seleccionadas intrasexualmente pueden haber sido reforzadas por selección intersexual. Los machos reproductivos presentaron un mayor contenido hipofisario de β-FSH y SL que aquellos no reproductivos, mientras que no se encontraron diferencias entre las hembras. No se encontraron diferencias entre los índices gonadosomáticos de los machos. Los individuos no reproductivos presentaron niveles plasmáticos mayores de cortisol para ambos sexos. Aunque los individuos reproductivos dominantes podrían estar inhibiendo la reproducción de los peces menos dominantes a través de interacciones de contacto físico, aumentando sus niveles de cortisol y disminuyendo el contenido hipofisario de FSH y SL, esto no se vería reflejado a nivel gonadal en nuestro diseño experimental.


Assuntos
Animais , Peixes , Perciformes/anatomia & histologia , Perciformes/fisiologia , Teste de Complementação Genética/veterinária
7.
Physiol Behav ; 99(4): 425-32, 2010 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-20045426

RESUMO

Timing of breeding to an optimal season is a requirement for a successful reproductive outcome in seasonally breeding species. Photoperiodic signals are capable of modifying the reproductive behaviour and reproductive systems in several vertebrate species. The cichlid fish Cichlasoma dimerus shows highly organized breeding activities and different social status. The aim of this study is to test whether C. dimerus reproductive behaviour (male aggressive behaviour and female choice) and reproductive physiology (GnRH3 morphometric parameters, pituitary hormones content and organ-somatic indexes) are modulated by photoperiod. Before spawning, dominant pairs were isolated and kept in opposite tanks of 20 l for one week, so they could see each other but not physically interact. Afterwards, a group was exposed for four weeks to a short photoperiod (8h light:16 h dark) (short photoperiod exposed animals: SP) while another group was exposed to a long photoperiod (14 h light:10h dark) (long photoperiod exposed animals: LP). Temperature was maintained constant. Behavioural experiments showed that male aggression related to territory selection and its defence is reduced in SP males. Further, SP females were never chosen. At the brain level we demonstrated that GnRH3 neuronal optical density of staining was reduced. Finally, at the pituitary level we showed that SP males showed low levels of beta-LH, PRL and GH in the pituitary, and that SP females showed no significant differences in the pituitary content of any hormone. Taken all together these results suggest that in C. dimerus the photoperiod is a relevant environmental cue related to reproductive behaviour and physiology.


Assuntos
Ciclídeos/fisiologia , Fotoperíodo , Fenômenos Reprodutivos Fisiológicos , Comportamento Sexual Animal/fisiologia , Análise de Variância , Animais , Encéfalo/citologia , Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Feminino , Proteínas de Peixes/metabolismo , Glicoproteínas/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Hematócrito/métodos , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Neurônios/metabolismo , Hormônios Hipofisários/metabolismo , Sistema Hipófise-Suprarrenal/fisiologia , Prolactina/metabolismo , Ácido Pirrolidonocarboxílico/análogos & derivados , Ácido Pirrolidonocarboxílico/metabolismo
8.
Biocell ; 33(1): 1-18, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19499881

RESUMO

Many characteristics of the South American teleost fish Cichlasoma dimerus (body size, easy breeding, undemanding maintenance) make it amenable to laboratory studies. In the last years, many of the fundamental aspects of its reproductive and developmental biology have been addressed in our laboratory. Rather recently, the immunohistochemical localization of pituitary hormones involved in reproduction and in background color adaptation has been described in both adult and developing individuals, and the role of FSH in ovarian differentiation has been established. These findings have been correlated with mapping of some of their brain-derived controlling hormones. The latter include brain-derived gonadotropins which were shown to be active in vitro in the control of pituitary hormone secretions. The emerging picture shows C. dimerus as an interesting species in which many of their basic features have already been investigated and which conform a solid platform for comparative studies correlating neurohormones, pituitary hormones and behavior, from the molecular to the organismic level.


Assuntos
Ciclídeos/embriologia , Ciclídeos/fisiologia , Gonadotropinas/metabolismo , Ovário/embriologia , Hormônios Hipofisários/metabolismo , Testículo/embriologia , Animais , Encéfalo/metabolismo , Feminino , Masculino , Ovário/citologia , Hipófise/anatomia & histologia , Hipófise/metabolismo , Reprodução , Testículo/citologia
9.
Biocell ; 33(1): 1-18, Apr. 2009. ilus, tab
Artigo em Inglês | BINACIS | ID: bin-127219

RESUMO

Many characteristics of the South American teleost fish Cichlasoma dimerus (body size, easy breeding, undemanding maintenance) make it amenable to laboratory studies. In the last years, many of the fundamental aspects of its reproductive and developmental biology have been addressed in our laboratory. Rather recently, the immunohistochemical localization of pituitary hormones involved in reproduction and in background color adaptation has been described in both adult and developing individuals, and the role of FSH in ovarian differentiation has been established. These findings have been correlated with mapping of some of their brain-derived controlling hormones. The latter include brain-derived gonadotropins which were shown to be active in vitro in the control of pituitary hormone secretions. The emerging picture shows C. dimerus as an interesting species in which many of their basic features have already been investigated and which conform a solid platform for comparative studies correlating neurohormones, pituitary hormones and behavior, from the molecular to the organismic level.(AU)


Assuntos
Masculino , Animais , Feminino , Encéfalo/metabolismo , Ciclídeos/embriologia , Ciclídeos/fisiologia , Gonadotropinas/metabolismo , Ovário/embriologia , Hipófise/metabolismo , Testículo/citologia , Testículo/embriologia , Hormônios Hipofisários/metabolismo , Reprodução
10.
Biocell ; 33(1): 1-18, Apr. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-595024

RESUMO

Many characteristics of the South American teleost fish Cichlasoma dimerus (body size, easy breeding, undemanding maintenance) make it amenable to laboratory studies. In the last years, many of the fundamental aspects of its reproductive and developmental biology have been addressed in our laboratory. Rather recently, the immunohistochemical localization of pituitary hormones involved in reproduction and in background color adaptation has been described in both adult and developing individuals, and the role of FSH in ovarian differentiation has been established. These findings have been correlated with mapping of some of their brain-derived controlling hormones. The latter include brain-derived gonadotropins which were shown to be active in vitro in the control of pituitary hormone secretions. The emerging picture shows C. dimerus as an interesting species in which many of their basic features have already been investigated and which conform a solid platform for comparative studies correlating neurohormones, pituitary hormones and behavior, from the molecular to the organismic level.


Assuntos
Masculino , Animais , Feminino , Ciclídeos/embriologia , Ciclídeos/fisiologia , Encéfalo/metabolismo , Gonadotropinas/metabolismo , Hipófise/metabolismo , Hormônios Hipofisários/metabolismo , Ovário/embriologia , Testículo/citologia , Testículo/embriologia , Reprodução
11.
Neuroendocrinology ; 89(1): 27-37, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18758154

RESUMO

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) play key roles in vertebrate gametogenesis and steroidogenesis. They are mainly synthesized in the pituitary gland. While investigating the ontogeny of FSH and LH cells in the cichlid fish Cichlasoma dimerus by immunohistochemistry (IHC), we unexpectedly found immunoreactive neurons in the preoptic area, sending their projections through different brain areas and neurohypophysis. Our previous work using Western blot and IHC techniques applied to the adult brain confirmed these findings. To further demonstrate the extrapituitary expression of these hormones, we performed RT-PCR detecting sequences coding for beta-FSH and beta-LH subunits in the C. dimerus pituitary and brain (preoptic-hypothalamic area). The expression of these transcripts in both organs was consistent with their peptide expression showing a high sequence homology when compared with other phylogenetically related fish. An individual pituitary in vitro culture system was utilized to study the possible modulatory effect of brain-derived gonadotropins on pituitary hormone secretion. Pituitary explants were cultured with different concentrations of LH or FSH, and the culture media were analyzed by Western blot. Exogenous LH produced a dose-dependent increase in pituitary beta-LH, beta-FSH and somatolactin (SL) releases. No effect was observed on growth hormone (GH). The effect on prolactin (PRL) was not consistent among treatments. Exogenous FSH produced an inhibition in beta-LH release, dose-dependent increases in beta-FSH and SL releases, and no effect on PRL and GH releases. These findings support the concept of regulation of pituitary trophic hormones by brain-derived gonadotropins.


Assuntos
Subunidade beta do Hormônio Folículoestimulante/análise , Subunidade beta do Hormônio Folículoestimulante/genética , Hormônio Luteinizante Subunidade beta/análise , Hormônio Luteinizante Subunidade beta/genética , Hipófise/metabolismo , Área Pré-Óptica/química , RNA Mensageiro/análise , Sequência de Aminoácidos , Animais , Ciclídeos , Relação Dose-Resposta a Droga , Feminino , Proteínas de Peixes/metabolismo , Hormônio Foliculoestimulante/farmacologia , Subunidade beta do Hormônio Folículoestimulante/metabolismo , Expressão Gênica , Glicoproteínas/metabolismo , Hormônio do Crescimento/metabolismo , Imuno-Histoquímica , Hormônio Luteinizante/farmacologia , Hormônio Luteinizante Subunidade beta/metabolismo , Masculino , Dados de Sequência Molecular , Técnicas de Cultura de Órgãos , Hormônios Hipofisários/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos
12.
Cell Tissue Res ; 333(1): 49-59, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18506486

RESUMO

We detected a close morphological association between melanin-concentrating hormone (MCH)-immunoreactive (ir) fibers and somatolactin (SL)-ir cells in the pars intermedia of the cichlid fish Cichlasoma dimerus by double-label immunofluorescence. Male pituitaries obtained from adult C. dimerus were incubated with 0.1-10 microM salmon MCH, and the amount of SL released into the culture medium was semi-quantified by Western blot. This assay showed an increase of SL release in a dose-dependent manner (linear regression: P<0.05). A close association of GnRH-ir fibers with SL-ir cells was also detected at the pars intermedia level. Male pituitaries were also incubated with 0.1-10 microM of mammalian GnRH, and SL release was semi-quantified by Western blot, showing an increase of released SL levels in a dose-dependent manner (linear regression: P<0.05). In contrast, SL release was unaffected from female pituitaries incubated with salmon MCH; however, an increasing tendency was observed when mammalian GnRH was used. Hypothalamic close association of MCH-ir perikarya and GnRH-ir fibers was found by double-label immunofluorescence indicating a possible relationship between them. These results suggest that SL, like other pituitary hormones, is under hypothalamic control and is involved in diverse physiological processes including background adaptation and reproduction. This study has also shown that the in vitro culture of a single C. dimerus pituitary is a feasible method for studying the control of SL release and other pituitary hormones.


Assuntos
Ciclídeos/fisiologia , Proteínas de Peixes/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio do Crescimento/metabolismo , Hormônios Hipotalâmicos/farmacologia , Melaninas/farmacologia , Hormônios Hipofisários/farmacologia , Animais , Células Cultivadas , Meios de Cultura/química , Relação Dose-Resposta a Droga , Estudos de Viabilidade , Feminino , Hormônio do Crescimento/química , Cinética , Masculino , Peso Molecular , Hipófise/citologia , Isoformas de Proteínas , Reprodutibilidade dos Testes , Salmão , Fatores de Tempo
13.
J Exp Zool A Comp Exp Biol ; 305(5): 410-9, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16489555

RESUMO

Somatolactin (SL) is a pituitary hormone present exclusively in fish that is involved in different physiological processes. The role of SL was evaluated in Cichlasoma dimerus (Teleostei, Perciformes) exposed for 10 days to a black and white background (BB and WB). Changes in alpha-melanophore stimulating hormone (alphaMSH) and melanin concentrating hormone (MCH) cells were also analyzed for comparison with SL. A melanin dispersing effect was observed in fish exposed to a BB, while a concentrating one was observed in those exposed to a WB. By Western blot, three SL-immunoreactive (ir) bands (32, 28 and 23.5 kD) were evidenced. Pituitary SL-ir levels were 2.66- and 2.67-fold greater in the 32 Kd and 28 kD bands, respectively, in BB fish compared with those of WB fish. The SL-ir 23.5 Kd band was not included in the analysis because of its unknown identity. In addition, SL-ir cell number and area were significantly higher in the BB condition (BB 22.73+/-1.46, WB 7.37+/-0.54 and BB 27.39+/-1.00 microm2; WB: 16.61+/-0.65 microm2). No significant differences were observed in the number of the hypothalamic MCH-ir neurons. However, a significant difference was observed in their nuclear area (BB 11.61+/-0.42 microm2, WB 17.80+/-0.84 microm2). alphaMSH-ir cells showed a marked increased in number (BB 35.96+/-1.22, WB 24.36+/-1.04), but no significant differences were observed in the cell area. In conclusion, this study presented clear evidence towards a possible involvement of SL in the adaptation to background colors in teleost together with alphaMSH and MCH.


Assuntos
Adaptação Fisiológica , Ciclídeos/fisiologia , Meio Ambiente , Proteínas de Peixes/metabolismo , Glicoproteínas/metabolismo , Hormônios Hipofisários/metabolismo , Pigmentação da Pele/fisiologia , Pele/metabolismo , Animais , Contagem de Células , Núcleo Celular , Hormônios Hipotalâmicos/metabolismo , Hipotálamo/citologia , Hipotálamo/metabolismo , Melaninas/metabolismo , Hormônios Estimuladores de Melanócitos/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Hipófise/química , Hipófise/metabolismo
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