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1.
J Fish Biol ; 83(1): 1-13, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23808688

RESUMO

Muscle development in the bamboo sole Heteromycteris japonicus was investigated, focusing primarily on the cranial muscles, using an improved whole mount immunohistochemical staining method with potassium hydroxide, hydrogen peroxide and trypsin. Larvae of H. japonicus had branchial levators, but not all of them were retained in adults, a condition also seen in the Japanese flounder Paralichthys olivaceus. In particular, larval branchial levators II and III disappeared during development, while I and IV remained to become the levator internus I and levator posterior, which were well-defined muscles in adults. In place of the atrophied muscles, levatores externi and levator internus II developed and regulated the branchial arches. The results showed that the muscle composition in the dorsal branchial arches changed to the adult form before metamorphosis in H. japonicus, as seen in P. olivaceus, and this transformation may be common to all members of that group.


Assuntos
Linguados/crescimento & desenvolvimento , Desenvolvimento Muscular , Músculo Esquelético/crescimento & desenvolvimento , Animais , Região Branquial , Larva/crescimento & desenvolvimento , Metamorfose Biológica
2.
J Fish Biol ; 77(3): 627-42, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20701644

RESUMO

The effects of a tropical cyclone on the distribution of hatchery-reared black-spot tuskfish Choerodon schoenleinii were examined using acoustic telemetry. Nine fish were released in Urasoko Bay, Ishigaki Island, Japan, in September 2006, and another nine were released in June to July 2007, before a cyclone's passing through the area in September 2007. Data for the fish released in 2006 were used as the cyclone-inexperienced group to compare their distribution pattern to that of the 2007 cyclone-experienced group. Both groups of fish were monitored for up to 150 days. Of the nine fish in each group, four (44%) and two (22%) were monitored for over 150 days in the cyclone-inexperienced and the cyclone-experienced groups, respectively. Three of the five fish that had settled in the monitoring area left the area within a few days of the cyclone event. To estimate the time of disappearance of the fish, maximum wind speed during a period of 7 days (indicating the occurrence and intensity of the tropical cyclone), fish size and release year were evaluated as explanatory variables using a Cox proportional hazards model with Akaike's information criterion. The best predictive model included the effect of maximum wind speed. One fish that left the monitoring area displayed movement patterns related to strong winds, suggesting that wind-associated strong currents swept the fish away. No relationships were found between the movement patterns of the other two fish and any physical environmental data. The daily detection periods of one of the two fish gradually decreased after the cyclone hit, and this fish eventually left the monitoring area within 3 days, suggesting that it shifted to a habitat outside the monitoring area. These results indicate that tropical cyclones have both direct and indirect effects on the distribution of hatchery-reared C. schoenleinii.


Assuntos
Tempestades Ciclônicas , Perciformes/fisiologia , Clima Tropical , Acústica , Animais , Demografia , Feminino , Pesqueiros , Modelos Biológicos , Análise de Sobrevida , Natação , Telemetria/veterinária , Fatores de Tempo
3.
Fish Physiol Biochem ; 31(2-3): 157-61, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20035451

RESUMO

Vertebrate reproduction is under the neuroendocrine control of the hypothalamic decapeptide GnRH which synchronizes various reproductive events and influences other reproduction related aspects like spawning behavior and pheromonal action in fish. Multiple forms of GnRH peptides have been reported across diverse vertebrate and invertebrate classes. Here we report the partial seabream GnRH (sbGnRH) cDNA sequence cloned from the brain of Channa striatus (snake head murrel) a fresh water perciform with immense economic and medicinal value across Asiatic countries. sbGnRH mRNA was found in brain, gill and ovary of mature murrel with possible implications to the effect of GnRH on pheromonal phenomena and on reinitiation of oocyte meiosis. In keeping with the earlier reported role of GnRH in initiation of oocyte meiosis we here present evidence from RT-PCR, ICC demonstrating an increase in the level of sbGnRH mRNA in ovary from pre-vitellogenic to post-vitellogenic follicles.

4.
J Comp Neurol ; 356(1): 72-82, 1995 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-7629310

RESUMO

The immunocytochemical distribution of salmon gonadotropin-releasing hormone (sGnRH) and chicken GnRH-II (cGnRH-II) neurons in the brain of goldfish was examined using respective antisera. Salmon GnRH-immunoreactive (ir) cell bodies were localized in the area between the olfactory nerve and the olfactory bulb (the terminal nerve ganglion), the ventral telencephalon, the preoptic area, and the hypothalamus. Chicken GnRH-II-ir cell bodies were observed in the same areas as were those of sGnRH, although the number of cell bodies were fewer than those of sGnRH. In addition, chicken GnRH-II-ir cell bodies were also observed in the midbrain tegmentum where no sGnRH-ir cell bodies were found. Both sGnRH-ir and cGnRH-II-ir fibers were distributed not only in the hypothalamus and the pituitary gland but also in various brain areas from the olfactory bulb to the spinal cord. The wide distribution of GnRH-ir fibers suggests that in the goldfish, sGnRH and cGnRH-II not only regulate gonadotropin release from the pituitary gland but also function as neuromodulators in various brain regions.


Assuntos
Encéfalo/metabolismo , Carpa Dourada/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Animais , Encéfalo/imunologia , Mapeamento Encefálico , Feminino , Soros Imunes/imunologia , Imuno-Histoquímica , Bulbo Olfatório/imunologia , Bulbo Olfatório/metabolismo , Hipófise/imunologia , Hipófise/metabolismo , Área Pré-Óptica/imunologia , Área Pré-Óptica/metabolismo
5.
Int J Oncol ; 3(3): 457-65, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21573385

RESUMO

Nine cell lines were isolated after cotransfection of rat embryo fibroblasts with polyomavirus large-T (plt) and T24-ras oncogenes. Five of these lines were highly tumorigenic following subcutaneous injection, but differed in their metastatic and in vitro invasive properties. Two cell lines, expressing low levels of ras mRNA, showed low capacity for experimental metastasis. Three cell lines, expressing high levels of ras mRNA, were tumorigenic and showed high capacity for experimental metastasis. High expression of interstitial collagenase, stromelysin and 92 kDa type IV collagenase was observed in the highly metastatic cell lines. Immunochemical analysis revealed that these cell lines expressed apparently wild-type p53 protein. Furthermore, the level of a 43 kDa/pI 5,44 polypeptide was elevated and the levels of a series of 41 to 43 kDa acidic polypeptides were decreased in the metastatic cells. Within this panel of transformed cell lines, high capacity for experimental metastasis did not correlate with high chemoinvasive capacity in the reconstituted basal membrane assay. The limited invasive propensity could not be attributed to low chemotactic or adhesive capacity. We conclude that in vitro invasion does not correlate with experimental metastasis in this model system.

6.
J Neuroendocrinol ; 13(5): 395-400, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11328447

RESUMO

The effects of serotonin (5-HT), GABA and neuropeptide Y (NPY) on in vitro release of seabream (sb) gonadotropin releasing hormone (GnRH) from slices of the preoptic-anterior hypothalamus (P-AH) and pituitary of red seabream were studied. 5-HT, GABA and NPY all stimulated the release of sbGnRH from the P-AH but not from the pituitary of immature red seabream. They also stimulated sbGnRH release from the P-AH with a similar potency during the course of gonadal development. Specific agonists and/or antagonists of 5-HT, GABA and NPY showed that 5-HT and GABA utilize 5-HT(2) and GABAA receptor subtypes, respectively, to mediate their action, and that NPY employs at least NPY(Y1) and NPY(Y2) receptor subtypes to stimulate sbGnRH release. Combinations of different antagonists for 5-HT, GABA and noradrenaline/adrenaline did not block the stimulatory influence of NPY on release of sbGnRH, indicating that the action of NPY on the sbGnRH neuronal system is probably direct.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Neurotransmissores/farmacologia , Hipófise/metabolismo , Área Pré-Óptica/metabolismo , Dourada/metabolismo , Animais , Bicuculina/farmacologia , Epinefrina/antagonistas & inibidores , Feminino , Antagonistas GABAérgicos/farmacologia , Ketanserina/farmacologia , Masculino , Neuropeptídeo Y/agonistas , Neuropeptídeo Y/farmacologia , Norepinefrina/antagonistas & inibidores , Técnicas de Cultura de Órgãos , Hipófise/efeitos dos fármacos , Hipófise/crescimento & desenvolvimento , Área Pré-Óptica/efeitos dos fármacos , Área Pré-Óptica/crescimento & desenvolvimento , Reprodução , Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia , Ácido gama-Aminobutírico/farmacologia
7.
J Neuroendocrinol ; 11(3): 181-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10201813

RESUMO

Specific and sensitive radioimmunoassays (RIAs) were newly developed for two types of gonadotropin-releasing hormone (GnRH), namely, seabream (sb) GnRH and chicken (c) GnRH-II. We employed these two RIAs together with a previously reported RIA for salmon (s) GnRH to study the presence and regional distribution of these three GnRHs in the brains and pituitaries of four perciform fishes (red seabream, Pagrus major; black seabream, Acanthopagrus schlegeli; striped knifejaw, Oplegnathus fasciatus; and Nile tilapia, Oreochromis niloticus), as well as clarify seasonal changes in levels of these GnRHs in the brain and pituitary of red seabream. All three GnRHs were found in brains of all fishes examined, with regional distributions in the brains of the three GnRHs being rather similar. sbGnRH was abundant in telencephalon and hypothalamus. cGnRH-II was concentrated from the middle to posterior part of the brain and distributed throughout the brain. sGnRH was concentrated in the olfactory bulb and distributed all over the brain, as was cGnRH-II. The dominant form of GnRH in the pituitary was sbGnRH, with levels 500- to 2400-fold higher than those of sGnRH, while cGnRH-II was undetectable in all four species. In the brain and pituitary of female red seabream, levels of both brain and pituitary sbGnRH increased from October (immature phase) and reached a peak in April (spawning phase), reflecting the increase in gonadosomatic index and vitellogenesis. However, levels of sbGnRH remained high only in the pituitary of completely regressed fish in June. Levels of both sGnRH and cGnRH-II in the brain were higher in the regressed phase and remained lower during the spawning phase. From these and previous results, it appears that sbGnRH is physiologically the most important form of GnRH in reproduction in red seabream and, probably, in other perciforms also.


Assuntos
Encéfalo/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Hipófise/metabolismo , Estações do Ano , Animais , Feminino , Peixes , Radioimunoensaio
8.
Comp Biochem Physiol B Biochem Mol Biol ; 129(2-3): 251-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11399457

RESUMO

Exposure of Atlantic croaker (Micropogonias undulatus) to the polychlorinated biphenyl mixture (Aroclor 1254, PCB; 1 mg/kg body wt/day for 30 days) during the early-recrudescence phase of the gonadal cycle results in the impairment of LH secretion and gonadal growth. In order to determine whether impairment was due to disruption of the stimulatory GnRH neuroendocrine pathway, we compared various parameters of the GnRH-LH system in early recrudescing vs. spermiating (mature) fish. Seabream GnRH (GnRH) content in the preoptic anterior hypothalamic area (POAH) and pituitary, pituitary GnRH receptor concentrations, and basal and GnRH analog (GnRHa)-induced LH secretion were significantly higher in gonadally mature croaker compared to early-recrudescing fish. In a subsequent experiment, the effects of PCB on the same neuroendocrine indices were investigated during the gonadal recrudescence phase of croaker. PCB exposure during the period of testicular maturation prevented the natural increase in GnRH content in the POAH but not in the pituitary. This finding suggests that PCB may impair GnRH synthesis in the POAH. The number of pituitary GnRH receptors also remained significantly lower in the PCB-exposed group, which was likely due to an impairment of GnRH release. The GnRH content in the POAH, number of pituitary GnRH receptors, and LH secretion in the PCB-exposed group were comparable to those in early-recrudescing fish, suggesting an impairment of normal maturation of the GnRH-LH system during the gonadal recrudescence phase. This impairment may be due to a direct action of PCB on GnRH neurons and/or indirectly via interference with other neurotransmitter pathways that modulate GnRH function.


Assuntos
/farmacologia , Hormônio Liberador de Gonadotropina/metabolismo , Gônadas/crescimento & desenvolvimento , Hormônio Luteinizante/metabolismo , Perciformes/crescimento & desenvolvimento , Perciformes/metabolismo , Animais , Antitireóideos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Área Pré-Óptica/efeitos dos fármacos , Área Pré-Óptica/metabolismo , Maturidade Sexual
9.
Theriogenology ; 51(3): 569-82, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10729043

RESUMO

The Formosan landlocked salmon (Oncorhynchus masou formosanus) are at a high risk of extinction, and the sustained maintenance of the population will soon depend on aquaculture systems, which use cryopreservation of spermatozoa to increase genetic diversity. We investigated the effectiveness of dimethyl sulfoxide (DMSO), dimethyl-acetamide (DMA), and methanol as cryoprotectants in combination with 300 mM glucose as extender on the freezing of Formosan landlocked salmon spermatozoa. We also evaluated the morphological changes of Formosan landlocked salmon spermatozoa after their immediate dilution in the 300 mM glucose-DMSO extender and after freeze-thawing. The spermatozoa frozen with DMSO as a cryoprotectant showed significantly higher post-thaw motility and fertility than spermatozoa frozen with DMA or methanol. The fertilization capacity of frozen-thawed Formosan landlocked salmon was comparable to that of fresh spermatozoa. Intersubspecies fertilization trials between cryopreserved Formosan landlocked salmon spermatozoa and Amago salmon eggs showed high fertilization rates. Based on the findings, the potential value of using sperm bank to safeguard this endangered species is discussed.


Assuntos
Criopreservação/veterinária , Oncorhynchus , Espermatozoides , Animais , Variação Genética , Masculino , Microscopia Eletrônica , Oncorhynchus/genética , Dinâmica Populacional , Motilidade dos Espermatozoides , Espermatozoides/ultraestrutura
10.
PDA J Pharm Sci Technol ; 50(3): 172-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8696781

RESUMO

A new microwave continuous sterilizer (MWS) for applying microwave dielectric heating as an alternative to an autoclave was developed. The developmental objectives of the MWS were: 1. Achieving sufficient sterilization for the drugs containing heat-sensitive ingredients. 2. Measuring and recording sterilization temperature of each ampoule. 3. Ensuring automatic continuous operation and linkage with the preceding and following machines in an injection ampoule production process. The temperature of the drug solution in an ampoule was heated to 140 degrees C within about 30 seconds by the MWS. Target F0 value is achieved through the maintaining heater to maintain the target temperature for 12 seconds. Ampoules are cooled with air and water after completion of heating. The MWS is capable of processing 150 ampoules per minute. The newly developed techniques which minimized temperature distribution of heated ampoule solution were: 1. Microwave irradiation in a direction opposite to the direction of ampoules transportation. 2. Microwave irradiation in the lower part of ampoule solution (i.e., heating up the drug solution by thermal convection.) 3. Microwave power control by feedback of measured temperatures. 4. Heating rate control corresponding to the dielectric property of ampoule solution. The drug stability test was performed using 3% pyridoxamine phosphate solution, and the inactivation of spores in 3% pyridoxamine phosphate solution was examined using Bacillus stearothermophilus ATCC 7953 spores. The MWS was proved to have an adequate efficiency of sterilization with less chemical degradation of the contents than an autoclave.


Assuntos
Injeções , Micro-Ondas , Esterilização , Estabilidade de Medicamentos , Soluções , Temperatura
11.
Gan To Kagaku Ryoho ; 20(6): 821-3, 1993 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-8098199

RESUMO

The authors attempted to estimate the relationship between three biological parameters (nuclear DNA content, PCNA (proliferating cell nuclear antigen)/cyclin, HER-2/neu oncoprotein) and lymph node metastasis. We evaluated 37 breast cancers which were less than 2 cm in maximum dimension. Quantitative analysis was performed using a CAS 200 Image Analysis System, after Feulgen staining and immunochemical staining using anti-PCNA/cyclin monoclonal antibody and anti-HER-2/neu oncoprotein polyclonal antibody. In lymph node-negative cases 20.0% were aneuploid, while in lymph node-positive cases 58.8% were aneuploid. A total of 20.0% lymph node-negative cases were in the high proliferation group, as opposed to 52.9% of lymph node-positive cases. This analysis revealed a significant relationship between cell proliferation and lymph node metastasis. Analysis of the expression of HER-2/neu oncoprotein revealed no significant relationship between overexpression of HER-2/neu oncoprotein and lymph node metastasis, but the expression of HER-2/neu oncoprotein was significantly related to a shorter relapse-free survival.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Divisão Celular , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Feminino , Histocitoquímica , Humanos , Metástase Linfática , Proteínas Nucleares/análise , Proteínas Oncogênicas Virais/análise , Ploidias , Prognóstico , Antígeno Nuclear de Célula em Proliferação
12.
Sci Total Environ ; 499: 154-65, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25181047

RESUMO

Aerosol samples were collected in autumn 2007 on day- and nighttime basis in the northern receptor site of Beijing, China. The samples were analyzed for total carbon (TC) and water-soluble dicarboxylic acids (C2-C12), oxocarboxylic acids (C2-C9), glyoxal and methylglyoxal to better understand the photochemical aging of organic aerosols in the vicinity of Beijing. Concentrations of TC are 50% greater in daytime when winds come from Beijing than in nighttime when winds come from the northern forest areas. Most diacids showed higher concentrations in daytime, suggesting that the organics emitted from the urban Beijing and delivered to the northern vicinity in daytime are subjected to photo-oxidation to result in diacids. However, oxalic acid (C2), which is the most abundant diacid followed by C3 or C4, became on average 30% more abundant in nighttime together with azelaic, ω-oxooctanoic and ω-oxononanoic acids, which are specific oxidation products of biogenic unsaturated fatty acids. Methylglyoxal, an oxidation product of isoprene and a precursor of oxalic acid, also became 29% more abundant in nighttime. Based on a positive correlation between C2 and glyoxylic acid (ωC2) in nighttime when relative humidity significantly enhanced, we propose a nighttime aqueous phase production of C2 via the oxidation of ωC2. We found an increase in the contribution of diacids to TC by 3 folds during consecutive clear days. This study demonstrates that diacids and related compounds are largely produced in the northern vicinity of Beijing via photochemical processing of organic precursors emitted from urban center and forest areas.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Ácidos Dicarboxílicos/análise , Monitoramento Ambiental , Processos Fotoquímicos , Aerossóis/química , Movimentos do Ar , Poluentes Atmosféricos/química , Atmosfera/química , China , Ácidos Dicarboxílicos/química
14.
Pathol Int ; 49(4): 342-6, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10365855

RESUMO

A rare case of malignant fibrous histiocytoma of giant cell type originating in the lung of a 46-year-old woman is presented. The patient complained of having a cough that had lasted for a few weeks. A chest X-ray photograph showed a tumor shadow on the left lung. Histological and cytological examination of the biopsy specimen revealed that the tumor was a kind of sarcoma. An operative procedure was selected because of tumor invasion into the trunk of the left pulmonary artery, which was discovered on computed tomography examination, and because metastatic tumor was excluded clinically. The tumor was almost encapsulated and 6 x 6 x 6 cm in size; however, it also showed invasion into the pulmonary artery and bronchial lumen. A histological survey of the tumor showed a wide range of patterns such as fibrous, pleomorphic, fascicular and osteoclast-like giant cell figures; however, the osteoclast-like giant cell area was predominant. Immunohistochemically, the tumor cells were positive for vimentin, CD68 for histiocytic marker and alpha1-antichymotrypsin, and negative for keratin, epithelial membrane antigen, S-100 protein, MT-1, desmin, myoglobin and lysosome. No primary tumor was found clinically in any part of the patient's body at 2 and 4 months after operation. Consequently, she was diagnosed as having primary giant cell malignant fibrous histiocytoma of the lung.


Assuntos
Histiocitoma Fibroso Benigno/patologia , Neoplasias Pulmonares/patologia , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Biomarcadores Tumorais/metabolismo , Biópsia , Feminino , Células Gigantes/metabolismo , Células Gigantes/patologia , Histiocitoma Fibroso Benigno/diagnóstico por imagem , Histiocitoma Fibroso Benigno/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Pessoa de Meia-Idade , Radiografia
15.
Gen Comp Endocrinol ; 94(2): 199-206, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7523239

RESUMO

The effects of human chorionic gonadotropin (HCG) and 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (DHP) on in vitro germinal vesicle breakdown (GVBD) in oocytes obtained at different times of day from a daily spawning marine teleost, the red seabream Pagrus major, were investigated. Oocytes isolated at 0800 hr underwent GVBD in response to HCG (10 IU/ml) but not to DHP (10 ng/ml). GVBD could be induced in oocytes isolated at 1600 hr by either HCG or DHP. Oocytes underwent GVBD in response to DHP after DHP-insensitive oocytes were incubated with HCG for 30, 60, or 120 min. The effects of actinomycin D (a transcriptional inhibitor) and cycloheximide (a translational inhibitor) on HCG- and DHP-induced GVBD were also investigated. Actinomycin D (1 microgram/ml) totally inhibited HCG-induction of GVBD in oocytes isolated at 0600 and 0800 hr. Actinomycin D also significantly inhibited GVBD induced by HCG in combination with DHP in oocytes taken at 0600 and 0800 hr. Cycloheximide (1 microgram/ml) completely inhibited the inducation of GVBD by HCG or DHP, alone or in combination, in oocytes obtained at 0600, 1000, and 1400 hr. These results indicate that gonadotropin induces maturational competence (responsiveness to maturation-inducing steroid) in oocytes of red seabream. These results also suggest that gonadotropin-induced synthesis of new protein through a mechanism dependent on RNA is essential for the development of maturational competence in oocytes of red seabream.


Assuntos
Gonadotropina Coriônica/farmacologia , Peixes/fisiologia , Oócitos/crescimento & desenvolvimento , Biossíntese de Proteínas , RNA/biossíntese , Animais , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Feminino , Humanos , Hidroxiprogesteronas/farmacologia , Oócitos/efeitos dos fármacos , Oócitos/metabolismo
16.
Fish Physiol Biochem ; 10(5): 409-18, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24214379

RESUMO

Two gonadotropic glycoproteins (PmGTH I and II) were purified by ion-exchange chromatography, gel filtration and preparative SDS-PAGE, from pituitaries of red seabream, a marine teleost which has an asynchronous-type ovary and spawns almost daily during the spawning season. The glycoproteins were composed of distinct subunits and the molecular weights were estimated to be 32 and 38 kDa for PmGTH I and PmGTH II, respectively. Both PmGTH I and II were active in two homologous bioassays: in vitro oocyte maturation and/or in vitro estradiol-17ß production assays. These two GTHs were distinct in electrostatic properties, molecular weight, stability and yields from pituitaries during the spawning season. These properties suggest that PmGTH I and II correspond to salmon GTH I and II, respectively.A homologous radioimmunoassay with which to measure PmGTH II was developed using a rabbit antiserum against the ß subunit of PmGTH II and intact PmGTH II as standards and radioactive competitors. Competition curves for red seabream plasma and pituitary extract were parallel to the standard curve, while PmGTH I had low cross-reactivity (3.1 %) with the antibody. This specific RIA system showed an in vivo LHRHa induced GTH surge in the plasma of female red seabream.

17.
Gen Comp Endocrinol ; 110(1): 11-8, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9514846

RESUMO

Immunocytochemical identification of GTH I and GTH II cells in the pituitary of the bluefin tuna (Thunnus thynnus) was performed using antisera specific for the common alpha-subunit and the two distinct beta-subunits of tuna (Thunnus obesus) GTH I and GTH II. Cells of the dorsal part of the proximal pars distalis (PPD), in close association with somatotrophs, displayed immunoreactivity of GTHIbeta. GTH IIbeta immunoreactivity was present in cells of the central part of the PPD and the external border of the pars intermedia. Anti-GTHalpha immunostained both GTH Ibeta- and GTH IIbeta-immunoreactive cells and also thyrotrophs. Both GTH Ibeta- and GTH IIbeta-immunoreactive cells were observed in immature bluefin tuna, although there were greater numbers of GTH IIbeta immunoreactive cells. These results suggest that GTH I and GTH II are synthesized in separate cells in the pituitary of the bluefin tuna. The localization and appearance of the two distinct gonadotropic cells of the tuna are compared with the salmonid arrangement.


Assuntos
Gonadotropinas Hipofisárias/análise , Hipófise/metabolismo , Atum/metabolismo , Animais , Feminino , Imuno-Histoquímica , Masculino , Hipófise/citologia , Atum/anatomia & histologia
18.
Gen Comp Endocrinol ; 112(1): 80-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9748406

RESUMO

The effects of red seabream gonadotropins (PmGTH I and PmGTH II) on the induction in vitro of germinal vesicle breakdown (GVBD) and the development of maturational competence (responsiveness to maturation-inducing steroid) were examined in the oocytes of red seabream. PmGTH II was highly effective in inducing GVBD in both maturationally incompetent (45.6 +/- 3.2% GVBD at a concentration of 300 ng/ml) and competent oocytes (42.3 +/- 0.4% GVBD at a concentration of 300 ng/ml). 17,20beta-Dihydroxy-4-pregnen-3-one (DHP, 10 ng/ml) increased the frequency of GVBD induced by PmGTH II. PmGTH I (33, 100, 300, and 900 ng/ml) was unable to induce GVBD at any tested concentration in the presence or absence of DHP. Actinomycin D (1 microgram/ml) and cycloheximide (1 microgram/ml) totally inhibited the PmGTH II-induced GVBD in the presence and in the absence of DHP. Both PmGTH I and PmGTH II stimulated in vitro production of 11-ketotestosterone in sliced testes of red seabream in a similar potency. These results indicate that PmGTH II, but not PmGTH I, induces the final maturation of oocytes, as well as the development of the maturational competence of oocytes, in red seabream.


Assuntos
Gonadotropinas Hipofisárias/farmacologia , Oócitos/crescimento & desenvolvimento , Perciformes/fisiologia , Animais , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Feminino , Hidroxiprogesteronas/farmacologia , Masculino , Inibidores da Síntese de Ácido Nucleico/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testosterona/análogos & derivados , Testosterona/biossíntese
19.
Gen Comp Endocrinol ; 75(1): 139-47, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2767403

RESUMO

The honmoroko (Gnathopogon caerulescens), a small, spring-summer-breeding cyprinid fish, was exposed to various temperature and photoperiod regimes during different phases of its annual reproductive cycle. In autumn, a clear photoperiodism was seen, especially at warm temperatures (18-24 degrees). The gonadosomatic index, plasma gonadotropin (GtH), and gonadal steroids were higher in fish held at long photoperiod (15L/9D) than in those held at short photoperiod (12L/12D); the differences were greater as the temperature increased. In early spring, gonadal recrudescence progressed at temperatures above 7 degrees, regardless of photoperiod. Photoperiod did not affect plasma GtH and gonadal steroid levels at this time of the year. During its spawning season, a long photoperiod (15L/9D) was again required to maintain gonadal activity and high plasma GtH and gonadal steroid levels, especially at high temperature (25 degrees). In early summer, high temperatures (25 and 30 degrees) suppressed gonadal activity; however, gonadal steroid levels were not depressed, and plasma GtH levels actually increased. The data suggest that under natural conditions, high water temperatures in summer may act directly at the gonadal level, and is probably the factor which terminates the breeding season for this species. The results of these four experiments indicate that the honmoroko exhibits a photoperiodic response during the autumn month and its spawning season, and is dependent on the water temperature. The effects of photoperiod on gonadal maturation appear to be GtH mediated, whereas the suppressive effects of high temperature are not.


Assuntos
Cyprinidae/fisiologia , Gonadotropinas/sangue , Luz , Ovário/fisiologia , Esteroides/sangue , Temperatura , Testículo/fisiologia , Animais , Estrogênios/sangue , Feminino , Gonadotropinas/farmacologia , Masculino , Oogênese , Reprodução/efeitos dos fármacos , Espermatogênese , Esteroides/farmacologia , Testosterona/sangue
20.
Gen Comp Endocrinol ; 96(2): 234-42, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7851723

RESUMO

Complementary DNA fragments encoding the prepro-salmon gonadotropin-releasing hormone ([Trp7, Leu8]GnRH, sGnRH) of the red seabream Pagrus major were amplified from mRNA of the olfactory bulbs using a reverse transcriptase-polymerase chain reaction (RT-PCR), and the full-length cDNA was cloned from a cDNA library using the PCR-amplified cDNA as a probe. The cDNA consisted of 442 bp, including an open reading frame of 270 bp which encoded the prepro-sGnRH (90 amino acid residues). The prepro-sGnRH had the same architecture as that reported in other species. It was composed of a signal peptide, sGnRH and a GnRH-associated peptide (GAP), which was connected to sGnRH by a Gly-Lys-Arg sequence. The prepro-sGnRH of the red seabream had 90% amino acid identity to the prepro-sGnRH from an African cichlid Haplochromis burtoni which belongs to the same suborder as the red seabream; however, identity was lower to the prepro-sGnRH from Atlantic salmon Salmo salar (74%) and masu salmon Oncorhynchus masou (70%). The GnRH peptide itself and the Gly-Lys-Arg sequence in the prepro-GnRH are highly conserved among vertebrates. The red seabream GAP also shows significant amino acid identity to the GAPs of the African cichlid (89%), Atlantic salmon (74%), and masu salmon (67%), but exhibits no significant identity to chicken or mammalian GAP.


Assuntos
Peixes/genética , Hormônio Liberador de Gonadotropina/análogos & derivados , Precursores de Proteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Clonagem Molecular , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/isolamento & purificação , Humanos , Camundongos , Dados de Sequência Molecular , Precursores de Proteínas/isolamento & purificação , RNA Mensageiro/análise , Ratos , Salmão
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