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1.
Gan To Kagaku Ryoho ; 46(3): 457-461, 2019 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-30914584

RESUMO

BACKGROUND: Prophylactic granulocyte-colony stimulating factor(G-CSF)is necessary for some cancer patients receiving anti-cancer drugs. However, it is difficult for cancer patients in rural areas to receive G-CSF as outpatients because of inconvenient official transport, lack of public support, and low activity levels due to age. To resolve this problem, we began conducting a critical path(G-path)with regional medical institutions from 2011. METHODS: We retrospectively surveyed the clinical records of cancer patients receiving prophylactic G-CSF using G-path at our hospital. RESULTS: Eighty-two patients who were administered a total of 254 cycles of chemotherapy were examined between January 2011 and December 2016. Diseases included malignant lymphoma(n=64), pancreatic cancer(n=7), soft tissue sarcoma(n=5), and others(n=6). The median age of the patients was 70(range: 24-94)years. Fifty-three patients visited medical offices, and 31 patients visited regional hospitals. In 245 of 254(96%)cycles, planned G-CSF administration was performed. In 37 of 254(15%)cycles, infectious episodes developed, but patients needed hospitalization for only 5 cycles(2%). CONCLUSION: Cooperation between clinics and hospitals using G-path reduced ambulatory burden and prevented severe infection. Cooperation in supportive care may allow for equal accessibility to cancer treatment.


Assuntos
Procedimentos Clínicos , Fator Estimulador de Colônias de Granulócitos , Neutropenia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Pessoa de Meia-Idade , Neutropenia/prevenção & controle , Estudos Retrospectivos , Adulto Jovem
2.
Drug Dev Ind Pharm ; 42(1): 116-122, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25997364

RESUMO

BACKGROUND: Granule characteristics are some of the important intermediate qualities that determine tablet properties. However, the relationships between granule and tablet characteristics are poorly understood. The aim of this study was to elucidate relationships among formulation factors, granule characteristics, and tablet properties using a non-linear response surface method (RSM) incorporating a thin-plate spline interpolation (RSM-S) and a Bayesian network (BN). METHOD: Tablets containing lactose (Lac), cornstarch (CS), and microcrystalline cellulose (MCC) were prepared by wet granulation. Ten formulations were prepared by an extreme vertices design. The angle of repose (Y1), compressibility (Y2), cohesion force (Y3), internal friction angle (Y4), and mean particle size (Y5) were measured as granule characteristics. Tensile strength (TS) and disintegration time (DT) were measured as tablet properties. RESULTS: RSM-S results showed that TS increased with increasing amounts of MCC and Lac. DT decreased with increasing amounts of MCC and CS. The optimal BN models were predicted using four evaluation indices -Y3 was shown to be the most important factor for TS, whereas Y2, Y3, and Y4 were relatively important for predicting DT. Moreover, tablets with excellent tablet properties (i.e. high TS and low DT) were produced by relatively high Y1, low Y2, high Y3, high Y4, and middle Y5 values, and resulted from the middle of MCC, middle-to-low CS, low Lac, and middle-to-low magnesium stearate (Mg-St) amounts. CONCLUSION: The RSM-S and BN techniques are useful for revealing complex relationships among formulation factors, granule characteristics, and tablet properties.


Assuntos
Composição de Medicamentos/métodos , Excipientes/química , Comprimidos/química , Teorema de Bayes , Celulose/química , Lactose/química , Modelos Teóricos , Tamanho da Partícula , Amido/química , Resistência à Tração
3.
Am J Physiol Regul Integr Comp Physiol ; 307(1): R44-56, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24717674

RESUMO

Two types of aquaporin 5 (AQP5) genes (aqp-xt5a and aqp-xt5b) were identified in the genome of Xenopus tropicalis by synteny comparison and molecular phylogenetic analysis. When the frogs were in water, AQP-xt5a mRNA was expressed in the skin and urinary bladder. The expression of AQP-xt5a mRNA was significantly increased in dehydrated frogs. AQP-xt5b mRNA was also detected in the skin and increased in response to dehydration. Additionally, AQP-xt5b mRNA began to be slightly expressed in the lung and stomach after dehydration. For the pelvic skin of hydrated frogs, immunofluorescence staining localized AQP-xt5a and AQP-xt5b to the cytoplasm of secretory cells of the granular glands and the apical plasma membrane of secretory cells of the small granular glands, respectively. After dehydration, the locations of both AQPs in their respective glands did not change, but AQP-xt5a was visualized in the cytoplasm of secretory cells of the small granular glands. For the urinary bladder, AQP-xt5a was observed in the apical plasma membrane and cytoplasm of a number of granular cells under normal hydration. After dehydration, AQP-xt5a was found in the apical membrane and cytoplasm of most granular cells. Injection of vasotocin into hydrated frogs did not induce these changes in the localization of AQP-xt5a in the small granular glands and urinary bladder, however. The results suggest that AQP-xt5a might be involved in water reabsorption from the urinary bladder during dehydration, whereas AQP-xt5b might play a role in water secretion from the small granular gland.


Assuntos
Aquaporina 5/metabolismo , Desidratação/metabolismo , Equilíbrio Hidroeletrolítico , Água/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus/metabolismo , Sequência de Aminoácidos , Animais , Aquaporina 5/genética , Clonagem Molecular , Desidratação/genética , Desidratação/fisiopatologia , Regulação da Expressão Gênica , Imuno-Histoquímica , Dados de Sequência Molecular , Osmorregulação , Filogenia , Isoformas de Proteínas , RNA Mensageiro/metabolismo , Pele/metabolismo , Sintenia , Bexiga Urinária/metabolismo , Xenopus/genética , Proteínas de Xenopus/genética
4.
Peptides ; 43: 40-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23422837

RESUMO

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide that stimulates the release of adenohypophyseal hormone from the pituitary in fish. In the goldfish, PACAP induces the release of somatolactin (SL), in particular, from cultured pituitary cells. SL belongs to the growth hormone and prolactin family, and comprises two molecular variants termed SL-α and SL-ß in goldfish. However, there is no information about the involvement of PACAP in the regulation of SL-α and SL-ß release and the expression of their mRNAs. Therefore, we examined the effect of PACAP on SL-α and SL-ß release from cultured goldfish pituitary cells. Treatment with PACAP (10(-10)-10(-7)M) increased the release of both SL-α and SL-ß. The stimulatory action of PACAP (10(-9)M) on SL-α and SL-ß release was blocked by treatment with a PACAP-selective receptor (PAC1R) antagonist, PACAP(6-38) (10(-6)M). We also examined whether PACAP affects the expression of SL-α and SL-ß mRNAs in cultured pituitary cells. Treatment with PACAP (10(-9) and 10(-8)M) for 6h decreased the expression level of SL-α mRNA but increased that of SL-ß mRNA. The action of PACAP (10(-8)M) on SL-ß mRNA expression was blocked by treatment with PACAP(6-38) (10(-6)M), whereas PACAP(6-38) elicited no change in the expression of SL-α mRNA. These results indicate that in cultured goldfish pituitary cells, PACAP stimulates the release of SL-α and SL-ß, and expression of SL-ß mRNA, via the PAC1R-signaling pathway. However, the mechanism whereby PACAP inhibits the expression of SL-α mRNA does not seem to be mediated by PAC1R signaling.


Assuntos
Proteínas de Peixes/metabolismo , Glicoproteínas/metabolismo , Carpa Dourada , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Hipófise/citologia , Hormônios Hipofisários/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Animais , Células Cultivadas , Proteínas de Peixes/genética , Perfilação da Expressão Gênica , Glicoproteínas/genética , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Hormônios Hipofisários/genética , RNA Mensageiro/genética
5.
Cell Tissue Res ; 350(1): 167-76, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22729486

RESUMO

Somatolactin (SL) is a pituitary hormone belonging to the growth hormone/prolactin family of adenohypophyseal hormones. In teleost fish, SL is encoded by one or two paralogous genes, namely SL-α and -ß. Our previous studies have revealed that pituitary adenylate-cyclase-activating polypeptide stimulates SL release from cultured goldfish pituitary cells, whereas melanin-concentrating hormone suppresses this release. As in other fish, the goldfish possesses SL-α and -ß. So far, however, no useful means of detecting the respective SLs immunologically in this species has been possible. In order to achieve this aim, we raised rabbit antisera against synthetic peptide fragments deduced from the goldfish SL-α and -ß cDNA sequences. Using these antisera, we observed adenohypophyseal cells showing SL-α- and -ß-like immunoreactivities in the goldfish pituitary, especially the pars intermedia (PI). Several cells in the PI showed the colocalization of SL-α- and -ß-like immunoreactivities. Then, using single-cell polymerase chain reaction with laser microdissection, we examined SL-α and -ß gene expression in adenohypophyseal cells showing SL-α- or -ß-like immunoreactivity. Among cultured pituitary cells, we observed three types of cell: those that possess transcripts of SL-α, -ß, or both. These results suggest a polymorphism of SL-producing cells in the goldfish pituitary.


Assuntos
Proteínas de Peixes/metabolismo , Glicoproteínas/metabolismo , Carpa Dourada/metabolismo , Hipófise/citologia , Hipófise/metabolismo , Hormônios Hipofisários/metabolismo , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos/imunologia , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Regulação da Expressão Gênica , Glicoproteínas/química , Glicoproteínas/genética , Glicoproteínas/imunologia , Hormônio do Crescimento , Soros Imunes/imunologia , Imuno-Histoquímica , Lasers , Microdissecção , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/imunologia , Adeno-Hipófise/citologia , Adeno-Hipófise/metabolismo , Hormônios Hipofisários/química , Hormônios Hipofisários/genética , Hormônios Hipofisários/imunologia , Prolactina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência
6.
Peptides ; 32(9): 1872-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21864603

RESUMO

Corticotropin-releasing factor (CRF) and CRF-related peptides exert hypophysiotropic and anorexigenic effects in mammals and teleost fish. In anuran amphibians, CRF acts as a potent stimulator of thyrotropin release from the pituitary. According to our recent study, CRF also acts as an anorexigenic factor for the cessation of food intake in the metamorphosing bullfrog larvae. However, the anorexigenic action of CRF has not been confirmed in adult bullfrogs. In this context, we examined the effect of feeding status on the expression level of the CRF transcript in the hypothalamus of the adult bullfrog. Levels of CRF mRNA in the hypothalami from bullfrogs fasted for 7 days were lower than in those from the bullfrogs that had been fed normally. Subsequently, we developed a method for measuring food intake in adult bullfrogs, and then investigated the effect of CRF on their food consumption in these animals. Intracerebroventricular (ICV) administration of CRF at 1 and 10pmol/g body weight (BW) induced a significant decrease of food intake during 60min. The CRF-induced anorexigenic action was blocked by treatment with a CRF receptor 1/CRF receptor 2 antagonist, α-helical CRF((9-41)), at 100pmol/g BW. These results provide direct evidence for the inhibitory effect of CRF on food intake, and suggest the involvement of CRF in the regulation of feeding through a CRF receptor-signaling pathway in the adult bullfrog.


Assuntos
Hormônio Liberador da Corticotropina/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Hipotálamo/metabolismo , Fragmentos de Peptídeos/farmacologia , Rana catesbeiana/fisiologia , Animais , Depressores do Apetite/farmacologia , Peso Corporal , Hormônio Liberador da Corticotropina/administração & dosagem , Jejum/metabolismo , Hipotálamo/efeitos dos fármacos , Infusões Intraventriculares , RNA Mensageiro/metabolismo , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Transdução de Sinais , Fatores de Tempo
7.
Am J Physiol Regul Integr Comp Physiol ; 299(5): R1150-62, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20811008

RESUMO

Regions of specialization for water absorption across the skin of Bufonid and Ranid anurans were identified by immunohistochemistry and Western blot analysis, using antibodies raised against arginine vasotocin (AVT)-stimulated aquaporins (AQPs) that are specific to absorbing regions of Hyla japonica. In Bufo marinus, labeling for Hyla urinary bladder-type AQP (AQP-h2), which is also localized in the urinary bladder, occurred in the ventral surface of the hindlimb, pelvic, and pectoral regions. AQP-h2 was not detected in any skin regions of Rana catesbeiana, Rana japonica, or Rana nigromaculata. Hyla ventral skin-type AQP (AQP-h3), which is found in the ventral skin but not the bladder of H. japonica, was localized in the hindlimb, pelvic, and pectoral skins of Bufo marinus, in addition to AQP-h2. AQP-h3 was also localized in ventral skin of the hindlimb of all three Rana species and also in the pelvic region of R. catesbiana. Messenger RNA for AQP-x3, a homolog of AQP-h3, could be identified by RT-PCR from the hindlimb, pectoral, and pelvic regions of the ventral skin of Xenopus laevis, although AVT had no effect on water permeability. In contrast, 10(-8) M AVT-stimulated water permeability and translocation of AQP-h2 and AQP-h3 into the apical membrane of epithelial cells in regions of the skin of species where they had been localized by immunohistochemistry and Western blot analysis. Finally, water permeability of the hindlimb skin of B. marinus and all the Rana species was stimulated by hydrins 1 and 2 to a similar level as seen for AVT. The present data demonstrate species differences in the occurrence, distribution, and regulation of AQPs in regions of skin specialized for rapid water absorption that can be associated with habitat and also phylogeny.


Assuntos
Anuros/metabolismo , Aquaporina 2/metabolismo , Aquaporina 3/metabolismo , Absorção Cutânea , Pele/metabolismo , Água/metabolismo , Animais , Anuros/genética , Aquaporina 2/genética , Aquaporina 3/genética , Western Blotting , Bufonidae/metabolismo , Feminino , Membro Posterior , Imuno-Histoquímica , Masculino , Pelve , Permeabilidade , Transporte Proteico , RNA Mensageiro/metabolismo , Ranidae/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie , Vasotocina/análogos & derivados , Vasotocina/metabolismo , Xenopus laevis/metabolismo
8.
Biosci Biotechnol Biochem ; 74(2): 350-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20139614

RESUMO

Fucoidan exhibits various biological properties. We raised a novel antibody against fucoidan extracted from Cladosiphon okamuranus and developed a sandwich ELISA method to measure fucoidan. The fucoidan antibody was specific and did not cross-react with other polysulfated polysaccharides. Fucoidan recovery from serum and urine by ELISA was 86-113%. Intra- and inter-assay CVs were 1.5-13.4%. Assay linearity was maintained after 3-fold dilution of each sample with phosphate-buffer saline (PBS). In the serum and urine of healthy volunteers (n=10), fucoidan was not detected before administration, and the levels markedly increased 6 and 9 h after oral administration. The molecular weight of the serum fucoidan determined by HPLC gel filtration remained unchanged, whereas that of urine fucoidan was significantly reduced. This is the first ELISA method of measuring serum and urine fucoidan levels after oral administration. The method is simple, reliable, and practical for the analysis of samples, especially urine samples.


Assuntos
Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Polissacarídeos/sangue , Polissacarídeos/urina , Administração Oral , Adulto , Calibragem , Reações Cruzadas , Humanos , Masculino , Pessoa de Meia-Idade , Polissacarídeos/administração & dosagem
9.
Gen Comp Endocrinol ; 168(2): 280-6, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20064518

RESUMO

In submammalian vertebrates, corticotropin-releasing factor (CRF) acts as an anorexigenic neuropeptide as well as a potent stimulator of corticotropin and thyrotropin release from the pituitary. As a step for demonstrating the involvement of CRF in the feeding regulation of anuran larvae, which are known to stop feeding toward the metamorphic climax, we studied firstly the changes in the distribution of CRF-like immunoreactivity (CRF-LI) in the brain of metamorphosing bullfrog larvae. Neuronal cell bodies showing CRF-LI were invariably present in the thalamic regions throughout larval development. Cells with CRF-LI were also found in the hypothalamus. The number of cells with CRF-LI in the hypothalamus, but not in the thalamus, showed a significant increase as metamorphosis progressed. Immunoreactive nerve fibers were observed mainly in the median eminence, and became abundant as metamorphosis proceeded. The number of cells showing CRF-LI in the hypothalamus as well as the density of immunoreactive fibers in the median eminence decreased at the end of metamorphosis. Secondly, we examined the effect of intracerebroventricular (ICV) injection of CRF on the food intake in the premetamorphic larvae. ICV injection of CRF at 10 pmol/g body weight (BW) induced a significant decrease of food intake during 15 min. The CRF-induced anorexigenic action was blocked by the treatment with a CRF receptor antagonist [alpha-helical CRF(9-41)] at 100 pmol/g BW. The results suggest the involvement of CRF in the accomplishment of metamorphosis through the pituitary and in the feeding restriction that occurs during the later stages of metamorphosis through the central nervous system.


Assuntos
Hormônio Liberador da Corticotropina/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Metamorfose Biológica/efeitos dos fármacos , Animais , Hormônio Liberador da Corticotropina/metabolismo , Antagonistas de Hormônios/farmacologia , Imuno-Histoquímica , Metamorfose Biológica/efeitos da radiação , Fragmentos de Peptídeos/farmacologia , Rana catesbeiana
10.
Endocrinology ; 151(1): 165-73, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19854867

RESUMO

Most adult anuran amphibians except for the aquatic species absorb water across the ventral pelvic skin and reabsorb it from urine in the urinary bladder. Many terrestrial and arboreal species use a region in the posterior or pelvic region of the ventral skin that is specialized for rapid rehydration from shallow water sources or moist substrates. Periods of terrestrial activity can be prolonged by reabsorption of dilute urine from the urinary bladder. Aquaporin (AQP), a water channel protein, plays a fundamental role in these water absorption/reabsorption processes, which are regulated by antidiuretic hormone. Characterization of AQPs from various anurans revealed that the unique water homeostasis is basically mediated by two types of anuran-specific AQPs, i.e. ventral pelvic skin and urinary bladder type, respectively. The bladder-type AQP is further expressed in the pelvic skin of terrestrial and arboreal species, together with the pelvic skin-type AQP. In contrast, the pelvic skin-type AQP (AQP-x3) of the aquatic Xenopus has lost the ability of efficient protein production. The extra C-terminal tail in AQP-x3 consisting of 33 nucleotides within the coding region appears to participate in the posttranscriptional regulation of AQP-x3 gene expression by attenuating protein expression. The positive transcriptional regulation of bladder-type AQP in the pelvic skin and negative posttranscriptional regulation of pelvic skin-type AQP provide flexibility in the water regulation mechanisms, which might have contributed to the evolutionary adaptation of anurans to a wide variety of water environments.


Assuntos
Adaptação Biológica/genética , Anuros/genética , Anuros/fisiologia , Aquaporinas/genética , Água/metabolismo , Adaptação Biológica/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Anuros/metabolismo , Aquaporinas/metabolismo , Aquaporinas/fisiologia , Ecossistema , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Variação Genética/fisiologia , Masculino , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Bexiga Urinária/metabolismo , Água/farmacologia , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Equilíbrio Hidroeletrolítico/genética
11.
Cell Tissue Res ; 333(2): 297-309, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18548281

RESUMO

Nucleotide sequences of cDNA were used to construct antibodies against an aquaporin (AQP) expressed in the clawed toad, Xenopus laevis, viz., Xenopus AQP3, a homolog of mammalian AQP3. Xenopus AQP3 was immunolocalized in the basolateral membrane of the principal cells of the ventral skin, the urinary bladder, the collecting duct and late distal tubule of the kidney, the absorptive epithelial cells of the large intestine, and the ciliated epithelial cells of the oviducts. Therefore, we designated this AQP as basolateral Xenopus AQP3 (AQP-x3BL). The intensity of labeling for AQP-x3BL differed between the ventral and dorsal skin, with the basolateral membrane of the principal cells in the ventral skin showing intense labeling, whereas that in the dorsal skin was lightly labeled. AQP-x3BL was also immunolocalized in the basolateral membrane of secretory cells in the small granular and mucous glands of the skin. As AQP-x5, a homolog of mammalian AQP5, is localized in the apical membrane of these same cells, this provides a pathway for fluid secretion by the glands. Although Hyla AQP-h2 is translocated from the cytoplasm to the apical membrane of the Hyla urinary bladder in response to arginine vasotocin (AVT), AQP-h2 immunoreactivity in Xenopus bladder remains in the cytoplasm and barely moves to the apical membrane, regardless of AVT stimulation. AQP-x3 is localized in the basolateral membrane, even though the AVT-stimulated AQP-h2 does not translocate to the apical membrane. These findings provide new insights into AQP function in aquatic anurans.


Assuntos
Aquaporina 3/metabolismo , Células Epiteliais/metabolismo , Xenopus laevis/anatomia & histologia , Xenopus laevis/metabolismo , Animais , Aquaporina 3/genética , Transporte Biológico , Células Epiteliais/citologia , Masculino , Distribuição Tecidual , Água/metabolismo , Xenopus laevis/genética
12.
Endocrinology ; 148(12): 5891-901, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17872371

RESUMO

Water movement occurs across the plasma membrane of various cells of animals, plants, and microorganisms through specialized water-channel proteins called aquaporins (AQPs). We have identified a new member of the amphibian AQP family, AQP-h2K, from the kidneys of Hyla japonica. This protein consists of 280 amino acid residues with two NPA (Asn-Pro-Ala) sequence motifs and a mercury-sensitive cysteine residue just upstream from the second NPA motif. There are two putative N-linked glycosylation sites at Asn-120 and Asn-128 and one protein kinase A phosphorylation site at Ser-262. The AQP-h2K protein was specifically expressed in the apical membrane and/or cytoplasm of principal cells in the kidney collecting ducts. After stimulation with arginine vasotocin, it was translocated from the cytoplasmic pool to the apical membrane. Phylogenetic analysis of AQP proteins from anurans and mammals identified six clusters of anuran AQPs: types 1, 2, 3, and 5 and two anuran-specific types, designated a1 and a2. The cluster AQPa2 contains Hyla AQP-h2 and AQP-h3, which are expressed in the anuran urinary bladder and ventral pelvic skin. AQP-h2K belongs to the type 2, together with mammalian (human and mouse) AQP2, suggesting that AQP-h2K is an anuran ortholog of the neurohypophysial hormone-regulated mammalian AQP2 and that the AQP2 molecule is already present in the anuran mesonephros.


Assuntos
Anuros/metabolismo , Aquaporinas/metabolismo , Rim/efeitos dos fármacos , Filogenia , Vasotocina/farmacologia , Sequência de Aminoácidos , Animais , Anuros/genética , Aquaporinas/classificação , Aquaporinas/genética , Sequência de Bases , Western Blotting , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , Imunofluorescência , Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Rim/metabolismo , Dados de Sequência Molecular , Oócitos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Xenopus/metabolismo
13.
Peptides ; 28(9): 1784-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17482721

RESUMO

We have recently shown that corticotropin-releasing hormone (CRH) is a major thyrotropin (TSH)-releasing factor in amphibians, but we have also found that, besides CRH, other hypothalamic substances stimulate TSH secretion in frog. In order to characterize novel TSH secretagogues, we have investigated the effect of frog (Rana ridibunda) vasoactive intestinal polypeptide (VIP) (fVIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) (fPACAP38 and PACAP27) on TSH release from bullfrog (Rana catesbeiana) pituitary cells in primary culture. Incubation of pituitary cells for 24h with graded concentrations of fVIP, fPACAP38 and PACAP27 (10(-9) to 10(-6)M) induced a dose-dependent stimulation of TSH release with minimum effective doses of 10(-9)M for fVIP and 10(-8)M for fPACAP38 and PACAP27. The PAC1-R/VPAC2-R antagonist PACAP(6-38) (10(-7) and 10(-6)M) dose-dependently suppressed the stimulatory effects of fVIP and fPACAP38 (10(-7)M each). Likewise, this antagonist (10(-6) and 10(-5)M) dose-dependently attenuated the stimulatory effect of PACAP27 (10(-7)M). On the other hand, the VPAC1-R/VPAC2-R antagonist [d-pCl-Phe(6), Leu(17)]VIP (10(-6) and 10(-5)M) dose-dependently inhibited the stimulatory effect of fVIP (10(-9)M) and PACAP27 (10(-8)M), but did not affect the response to fPACAP38 (10(-8)M). These data indicate that, in amphibians, the activity of thyrotrophs can be regulated by VIP and PACAP acting likely through VPAC2-R and PAC1-R.


Assuntos
Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Hipófise/efeitos dos fármacos , Tireotropina/metabolismo , Peptídeo Intestinal Vasoativo/farmacologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Hipófise/citologia , Hipófise/metabolismo , Rana catesbeiana , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/antagonistas & inibidores
14.
Gen Comp Endocrinol ; 138(3): 218-27, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15364204

RESUMO

Corticotropin-releasing factor (CRF) plays multiple roles in vertebrate species. In non-mammalian vertebrates, CRF has been considered to be the major thyrotropin (TSH)-releasing factor. This notion, however, was derived from experimental data on CRF of mammalian origin. Moreover, in the case of amphibians it has never been directly proved that CRF stimulates the release of TSH from the pituitary. The presently described experiment was conducted to provide direct evidence that homologous CRF enhances the release of TSH from the bullfrog (Rana catesbeiana) pituitary. First, cloning of cDNA encoding bullfrog CRF (fCRF) was accomplished. The cDNA encoding fCRF precursor was isolated from a cDNA library of the bullfrog hypothalamus. The amino acid sequence of fCRF predicted from the amplified cDNA sequence showed 83 and 95% identities with the sequences of ovine and human CRFs, respectively. An antiserum against the fCRF synthesized on the basis of the amino acid sequence was raised and used for immunohistochemical staining of the hypothalamus-hypophyseal region of the bullfrog brain. It stained some of the cell bodies situated mainly in the preoptic area, the nucleus infundibularis dorsalis and nucleus hypothalamicus ventralis and the axons that terminate in the median eminence and neural lobe. The synthetic fCRF was tested for its TSH-releasing activity toward anterior pituitary cells of adult bullfrogs in an in vitro system. As a result, the fCRF caused the release of TSH from the dispersed pituitary cells into the culture medium concentration-dependently, as measured by a specific radioimmunoassay for bullfrog TSH. The potency of the fCRF was almost equivalent to that of ovine CRF. Human urocortin III (hUCN III), a CRF receptor type 2 (CRF-R2) specific agonist enhanced the release of TSH from the pituitary cells in culture, suggesting the involvement of CRF-R2 in the CRF-induced TSH release in the bullfrogs. Culture of pituitary cells in the presence of the hypothalamic extract (HE) and alpha-helical CRF(9-41), a CRF-R antagonist, revealed that the antagonist suppressed the TSH-releasing activity of the HE by approximately 50%, suggesting that endogenous CRF contributes as a TSH-releasing factor.


Assuntos
Hormônio Liberador da Corticotropina/fisiologia , Hipotálamo/metabolismo , Hipófise/metabolismo , Rana catesbeiana/fisiologia , Tireotropina/metabolismo , Sequência de Aminoácidos , Análise de Variância , Animais , Sequência de Bases , Encéfalo/metabolismo , Células Cultivadas , Clonagem Molecular , Hormônio Liberador da Corticotropina/genética , DNA Complementar/isolamento & purificação , Biblioteca Gênica , Humanos , Dados de Sequência Molecular , Hipófise/citologia , Rana catesbeiana/genética , Homologia de Sequência de Aminoácidos , Distribuição Tecidual , Urocortinas
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