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1.
Nutrients ; 12(9)2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32825433

RESUMO

This study is part of the Children's Healthy Living program in U.S. Affiliated Pacific region. The objectives were to estimate overweight and obesity (OWOB) prevalence and identify possible related risk factors among ethnic groups in Guam. In 2013, 865 children (2-8 years) were recruited via community-based sampling from select communities in Guam. Children's demographic and health behavior information; dietary intake; and anthropometric measurements were collected. Logistic regression, odds ratio, t-tests, and chi-square tests were used to determine differences and assess covariates of OWOB. The results indicate that 58% of children were living below the poverty level, 80% were receiving food assistance, and 51% experienced food insecurity. The majority of children surveyed did not meet recommendations for: sleep duration (59.6%), sedentary screen-time (83.11%), or fruit (58.7%) and vegetable (99.1%) intake, and consumed sugar sweetened beverages (SSB) (73.7%). OWOB affected 27.4% of children. Children affected by OWOB in this study were statistically more likely (p = 0.042) to suffer from sleep disturbances (p = 0.042) and consume marginally higher amounts (p value = 0.07) of SSB compared to children with healthy weight. Among Other Micronesians, children from families who considered themselves 'integrated' into the culture were 2.05 (CI 0.81-5.20) times more likely to be affected by OWOB. In conclusion, the OWOB prevalence among 2-8-year-olds in Guam was 27.4%; and compared with healthy weight children, children with OWOB were more likely to have educated caregivers and consume more SSBs. Results provide a basis for health promotion and obesity prevention guidance for children in Guam.


Assuntos
Ingestão de Alimentos/fisiologia , Comportamento Alimentar/fisiologia , Inquéritos Epidemiológicos , Estilo de Vida , Obesidade Infantil/epidemiologia , Obesidade Infantil/etiologia , Constituição Corporal , Criança , Pré-Escolar , Dissonias/epidemiologia , Dissonias/etiologia , Escolaridade , Assistência Alimentar , Insegurança Alimentar , Guam/epidemiologia , Comportamentos Relacionados com a Saúde , Humanos , Obesidade Infantil/etnologia , Obesidade Infantil/psicologia , Pobreza , Prevalência , Fatores de Risco , Comportamento Sedentário , Bebidas Adoçadas com Açúcar/efeitos adversos
2.
J Vet Intern Med ; 26(3): 598-607, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22390318

RESUMO

BACKGROUND: Effective treatments for dogs with advanced stage mast cell tumors (MCT) remain a pressing need. A micellar formulation of paclitaxel (paclitaxel [micellar]) has shown promise in early-phase studies. HYPOTHESIS/OBJECTIVES: The objective was to demonstrate greater activity for paclitaxel (micellar) compared with lomustine. The null hypothesis was µ(p) = µ(L) (ie, proportion of responders for the paclitaxel [micellar] and lomustine groups, respectively). ANIMALS: Two hundred and fifty-two dogs with advanced stage nonresectable grade 2 or 3 MCT. METHODS: Prospective multicenter randomized double-blind positive-controlled clinical trial. The primary endpoint was confirmed overall response rate (CORR) at 14 weeks. A secondary endpoint, biologic observed response rate (BORR), also was calculated. Safety was assessed by the characterization and grading of adverse events (AE). RESULTS: Overall CORR (7% versus 1%; P = .048) and BORR (23% versus 10%; P = .012) were greater for paclitaxel (micellar) compared with lomustine. Paclitaxel (micellar)-treated dogs were 6.5 times more likely to have a confirmed response and 3.1 times more likely to experience a biologic observed response. The majority of AE with paclitaxel (micellar) were transient and clinically manageable. Twenty-seven dogs (33%) receiving lomustine were discontinued because of hepatopathy compared with 3 dogs (2%) receiving paclitaxel (micellar) (P < .0001; odds ratio 26.7). CONCLUSIONS AND CLINICAL IMPORTANCE: Paclitaxel (micellar)'s activity and safety profile are superior to lomustine. The addition of an active and novel taxane to the veterinary armamentarium could fill a substantial need and, as its mechanism of action and AE profile do not overlap with currently available TKI, its availability could lead to effective combination protocols.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Sarcoma de Mastócitos/veterinária , Micelas , Paclitaxel/uso terapêutico , Animais , Antineoplásicos Fitogênicos/química , Doenças do Cão/patologia , Cães , Método Duplo-Cego , Feminino , Masculino , Sarcoma de Mastócitos/tratamento farmacológico , Paclitaxel/química , Estudos Prospectivos , Estatísticas não Paramétricas , Resultado do Tratamento
3.
J Vet Intern Med ; 21(6): 1409-12, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18196755

RESUMO

BACKGROUND: Maitake PETfraction is a standardized essence extracted from the mushroom Maitake (Grifola frondosa) that has antitumor activity in tumor-bearing mice. In addition, PETfraction induces apoptosis in human prostate and bladder cancer cells and suppresses the proliferation in vitro of several canine tumor cell lines, such as lymphoma (Cl-1), mammary gland (CF33), and connective tissue (CF21). HYPOTHESIS: Maitake PETfraction is effective as a single agent in dogs with lymphoma. ANIMALS: Fifteen dogs with confirmed intermediate or high-grade lymphoma were enrolled into this prospective, noncontrolled, clinical trial. Inclusion criteria were an expected survival time of at least 2 weeks and no major organ dysfunction. METHODS: Maitake PETfraction was administered at a dose of 3 drops/kg/day divided into 2 doses given 1 hour before feeding. Dogs were evaluated by physical examination with tumor measurement, body weight, CBC, and chemistry profile before treatment and after 2, 4, 8, and 12 weeks. At each visit, owners completed a questionnaire addressing overall quality of life, appetite, and any adverse effects noted. RESULTS: A decrease in lymph node size of greater than 50% (objective response) was not seen in any of the dogs. Thirteen dogs developed progressive disease before the 4th week. The median treatment duration was 27 days (range, 9-228). PETfraction was well accepted, and minimal adverse effects were observed. Two dogs developed hyphema. It was not known if this was related to progressive lymphoma or was an adverse effect of treatment. CONCLUSIONS: No objective responses were observed to administration of Maitake PETfraction, and the drug was well tolerated in these dogs.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Grifola/química , Linfoma/veterinária , Fitoterapia/veterinária , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Fitogênicos/efeitos adversos , Antineoplásicos Fitogênicos/química , Cães , Feminino , Linfoma/tratamento farmacológico , Masculino , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química
4.
Environ Sci Technol ; 35(24): 4805-16, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11775156

RESUMO

This investigation into the occurrence, character, and transformation of dissolved organic matter (DOM) in treatment wetlands in the western United States shows that (i) the nature of DOM in the source water has a major influence on transformations that occur during treatment, (ii) the climate factors have a secondary effect on transformations, (iii) the wetlands receiving treated wastewater can produce a net increase in DOM, and (iv) the hierarchical analytical approach used in this study can measure the subtle DOM transformations that occur. As wastewater treatment plant effluent passes through treatment wetlands, the DOM undergoes transformation to become more aromatic and oxygenated. Autochthonous sources are contributed to the DOM, the nature of which is governed by the developmental stage of the wetland system as well as vegetation patterns. Concentrations of specific wastewater-derived organic contaminants such as linear alkylbenzene sulfonate, caffeine, and ethylenediaminetetraacetic acid were significantly attenuated by wetland treatment and were not contributed by internal loading.


Assuntos
Carbono/metabolismo , Conservação dos Recursos Naturais/métodos , Água Doce/química , Compostos Orgânicos/metabolismo , Oxigênio/metabolismo , Esgotos/química , Biodegradação Ambiental , Clima , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Oxirredução , Solo , Espectroscopia de Infravermelho com Transformada de Fourier , Estados Unidos
5.
Ann Vasc Surg ; 13(5): 484-93, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10466992

RESUMO

Hyperlipidemia contributes to the development of intimal hyperplasia and accelerated atheroma in vein bypass grafts. Dietary cholesterol reduction and oral supplementation with L-arginine have been shown to reduce accelerated atheroma in experimental vein grafts. This study extends these observations by examining the effect of the combination therapy of cholesterol reduction and L-arginine supplementation on the development of intimal hyperplasia in vein grafts in hypercholesterolemic animals. Thirty New Zealand White rabbits had a carotid vein bypass graft performed and were sacrificed at 28 days postoperatively either for morphology (light and electron microscopy) and videomorphometry, or for in vitro contractile studies. Twenty animals received a 1% cholesterol diet for 4 weeks prior to surgery. This diet was continued until harvest in ten animals. Ten cholesterol-fed animals received L-arginine supplementation (2 g/kg/day, p.o.) for 7 days preoperatively and thereafter until harvest and in addition were returned to a normal diet on the day of surgery. The last ten animals were controls (normal diet). Combined cholesterol reduction and L-arginine supplementation prevented accelerated atheroma in vein grafts, halted the change in enhanced smooth muscle cell contractility, and improved endothelial cell function. Early postoperative therapy targeting atheroma development in the high-risk patient could offer significant morphological and functional benefits.


Assuntos
Arginina/administração & dosagem , Arteriosclerose/prevenção & controle , Colesterol na Dieta/administração & dosagem , Dieta com Restrição de Gorduras , Suplementos Nutricionais , Veias Jugulares/transplante , Animais , Arteriosclerose/patologia , Arteriosclerose/fisiopatologia , Artérias Carótidas/cirurgia , Terapia Combinada , Endotélio Vascular/fisiopatologia , Hipercolesterolemia/dietoterapia , Hipercolesterolemia/cirurgia , Hiperlipidemias/prevenção & controle , Hiperplasia , Veias Jugulares/patologia , Veias Jugulares/fisiopatologia , Masculino , Microscopia Eletrônica , Microscopia de Vídeo , Músculo Liso Vascular/fisiopatologia , Coelhos , Túnica Íntima/patologia , Túnica Íntima/fisiopatologia , Vasoconstrição/fisiologia
6.
Eur J Vasc Endovasc Surg ; 15(4): 279-89, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9610339

RESUMO

OBJECTIVES: The universal response of vein grafts after insertion into the arterial circulation is the development of intimal hyperplasia; smooth muscle cell proliferation and connective tissue deposition, which may be modulated in part by dysfunctional endothelial nitric oxide (NO) metabolism. This study examines the effects of single dose, local application by pluronic gel of a NO donor, S-nitroso-N-acetylpenicillamine (SNAP) and an NO synthase inhibitor nitro-L-arginine methyl ester (L-NAME) on the formation of intimal hyperplasia. MATERIALS: Forty New Zealand white rabbits underwent jugular vein interposition grafting of the common carotid artery. DESIGN: Ten animals were controls, 10 animals had the outer surface of the vein graft coated with 30% pluronic gel (2.5 ml), and 10 each were immersed for 15 min prior to insertion in Ringer lactate containing 10(-3) M of SNAP or L-NAME and then had their vein grafts coated with 2.5 ml of gel containing either SNAP (10(-3) M) or L-NAME (10(-3) M), which allows for sustained delivery for up to 6 h. On the 28th post operative day, the animals were sacrificed and vein grafts were harvested for morphology by electron microscopy (SEM and TEM) and dimensional analysis by videomorphometry. RESULTS: All vein grafts developed intimal hyperplasia. On SEM the vein grafts had a confluent layer of endothelial cells with multiple layers of smooth muscle cells representing intimal hyperplasia in TEM. There were no demonstrable morphological differences between the four groups. Local treatment with SNAP produced a significant 36% decrease in mean intimal thickness (72 +/- 4 microns vs. 45 +/- 4 microns; mean +/- S.E.M.; p < 0.01) without a change in medial thickness compared to gel-only treated groups (58 +/- 6 microns vs. 61 +/- 7 microns; p = ns). Inhibition of NO synthase by L-NAME had no effect on the development of intimal hyperplasia (72 +/- 4 microns vs. 79 +/- 10 microns; p = ns); medial thickness was also unchanged. CONCLUSION: These data confirm the protective effect of NO in vascular injury and suggest that NO synthase activity is either absent or reduced to such a level that further inhibition in this short time course is not relevant to the pathophysiology of vein graft intimal hyperplasia.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/ultraestrutura , NG-Nitroarginina Metil Éster/administração & dosagem , Penicilamina/análogos & derivados , Veias/transplante , Animais , Artéria Carótida Primitiva/cirurgia , Divisão Celular/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Colágeno/biossíntese , Colágeno/efeitos dos fármacos , Colágeno/ultraestrutura , Citoplasma/efeitos dos fármacos , Citoplasma/ultraestrutura , Feminino , Hiperplasia/induzido quimicamente , Microscopia Eletrônica de Varredura , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/ultraestrutura , Penicilamina/administração & dosagem , Coelhos , Grau de Desobstrução Vascular , Veias/patologia
7.
J Surg Res ; 69(1): 128-34, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9202658

RESUMO

The development of intimal hyperplasia is recognized as a major impediment to graft patency. D-Limonenes are monoterpenes with a recognized cytostatic effect on cell proliferation by inhibiting posttranslational isoprenylation of p21ras and other small G-proteins. This study examines the effect of perillyl alcohol, an oral hydroxylated D-limonene, on the development of intimal hyperplasia and its associated smooth muscle cell physiological responses in an experimental model of vein bypass grafting. Twenty New Zealand white rabbits had a right carotid interposition bypass graft using the ipsilateral external jugular vein. Ten animals received chronic oral therapy with a perillyl alcohol (200 mg/kg/day; begun 5 days before surgery and continued until harvest) and 10 control animals received vehicle only. All animals were sacrificed on the 28th postoperative day. Vein grafts were harvested either for morphology/videomorphometry (n = 6 per group) or for in vitro isometric tension studies (n = 4; four 5-mm rings per graft). The cell proliferation and incorporation of [3H]thymidine into the cellular DNA of serum-stimulated rabbit aortic smooth muscle cells was also assessed in the presence of increasing concentrations of perillyl alcohol (10(-9)-10(-4) M). Perillyl alcohol treated vein grafts showed a 22% reduction in overall mean intimal thickness (54 +/- 4 microns vs 69 +/- 3 microns; P = 0.006) but a 25% increase in overall mean medial thickness (86 +/- 4 microns vs 61 +/- 3 microns). The intimal ratio of the perillyl alcohol treated vein grafts decreased by 27% compared to controls. Perillyl alcohol induced norepinephrine and serotonin hypersensitivity in vein grafts compared to controls. The IC50 for perillyl alcohol was 176 nM with maximal inhibition at 5 microM. Incubation of smooth muscle cell cultures with increasing concentrations of perillyl alcohol showed a dose-dependent decrease in in vitro cellular proliferation, maximal at 1 microM. Therapy with perillyl alcohol alters the early development of intimal hyperplasia reducing the intimal response but increasing the medial response without significant changes in the physiological responses of the smooth muscle cells. Modulating G-proteins will affect the intimal hyperplastic response in vein grafts.


Assuntos
Artéria Carótida Primitiva/cirurgia , Veias Jugulares/efeitos dos fármacos , Veias Jugulares/transplante , Monoterpenos , Terpenos/administração & dosagem , Túnica Íntima/efeitos dos fármacos , Administração Oral , Animais , Divisão Celular , Colágeno/biossíntese , Hiperplasia , Veias Jugulares/fisiopatologia , Coelhos , Terpenos/farmacologia , Timidina/metabolismo , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Vasoconstrição
8.
J Surg Res ; 59(1): 35-42, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7630134

RESUMO

Hyperlipidemia contributes to the development of intimal hyperplasia and subsequent accelerated atherosclerosis in vein bypass grafts. This study examines the effect of dietary supplementation with L-arginine on the development of intimal hyperplasia and the vasomotor function of vein grafts in hypercholesterolemic animals. Thirty male New Zealand White rabbits had a right carotid vein bypass graft and were sacrificed at 28 days postoperatively. Twenty animals received a 1% cholesterol diet for 4 weeks prior to surgery and this diet was continued until harvest. Of these, 10 also received L-arginine (2.25%, 2 g/kg, p.o.) 7 days preoperatively and thereafter until harvest. The last 10 animals were controls. Vein grafts were harvested either for morphology or for in vitro isometric tension studies. Cumulative dose-response curves to norepinephrine, serotonin, and bradykinin were recorded, and following norepinephrine precontraction, relaxation to acetylcholine and sodium nitroprusside were determined. After in situ pressure fixation, intimal thicknesses of the vein grafts were measured by videomorphometry. The addition of L-arginine doubled the serum arginine concentrations. Intimal hyperplasia of both groups of hypercholesterolemic vein grafts contained foam cells and lipid-laden endothelial and smooth muscle cells. There was a 24% reduction in the intimal thickness of vein graft intimal hyperplasia in the L-arginine group compared to that in the hypercholesterolemia group (P < 0.05). All hypercholesterolemic vein grafts were two-fold thicker than in the control group. L-arginine supplementation resulted in the preservation of acetylcholine-mediated relaxation but did not change hypercholesterolemia-induced contractile agonist supersensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Arginina/farmacologia , Arteriosclerose/prevenção & controle , Músculo Liso Vascular/patologia , Óxido Nítrico/fisiologia , Veias/transplante , Animais , Colesterol/sangue , Endotélio Vascular/patologia , Endotélio Vascular/ultraestrutura , Hiperplasia , Masculino , Coelhos , Vasoconstrição
9.
Angiology ; 46(2): 91-7, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7702205

RESUMO

Angiotensin-converting enzyme (ACE) inhibitors have been shown to reduce the intimal proliferation in animal models of arterial angioplasty and vein bypass grafting. This study examines the effect of high-dose ramipril, an ACE inhibitor that does not contain a sulfhydryl group, on the development of intimal hyperplasia in experimental vein bypass grafts. Twenty New Zealand White rabbits underwent common carotid interposition bypass grafting. Twelve were treated with ramipril (2 mg/kg/day; po) five days prior to surgery and thereafter until harvest. The remaining 8 animals were used as controls. Vein grafts were harvested at twenty-eight days by pressure fixation (80 mmHg). The grafts were sectioned into proximal, middle, and distal thirds, and the thickness of the intima and the media and the area of the lumen from each segment were determined by videomorphometry. The effect of ramipril on the [H3]thymidine incorporation into DNA of serum-stimulated smooth muscle cells (culture passage 6 to 12) was also assessed. There was a 50% mortality rate in the rabbits that received ramipril, and this was assumed to be related to the high dose of the drug. Ramipril treatment reduced mean vein graft intimal area by 34% (P > 0.05), but this was accompanied by an increase of 73% in the mean medial area of the vein grafts as compared with controls. These changes resulted in a decrease in the mean intimal ratio (intima/[intima + media]) by 39% in the ramipril group as compared with controls. Ramipril did not inhibit [H3]thymidine incorporation into DNA of serum-stimulated smooth muscle cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Oclusão de Enxerto Vascular/prevenção & controle , Veias Jugulares/transplante , Ramipril/uso terapêutico , Túnica Íntima/efeitos dos fármacos , Animais , Técnicas de Cultura , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Oclusão de Enxerto Vascular/metabolismo , Oclusão de Enxerto Vascular/patologia , Hiperplasia/metabolismo , Hiperplasia/patologia , Hiperplasia/prevenção & controle , Veias Jugulares/efeitos dos fármacos , Veias Jugulares/metabolismo , Veias Jugulares/patologia , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Coelhos , Distribuição Aleatória , Timidina/metabolismo , Túnica Íntima/metabolismo , Túnica Íntima/patologia , Túnica Média/efeitos dos fármacos , Túnica Média/metabolismo , Túnica Média/patologia
10.
Int J Radiat Biol ; 67(1): 57-64, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7852817

RESUMO

The polyethoxylated castor oil, Cremophor EL (Cremophor) is approved for human use as a vehicle for oral and intravenous administration of water-insoluble compounds. Cremophor has also previously been shown to reverse the multidrug resistance phenotype at clinically acceptable doses. This study demonstrates that doses of Cremophor in the range of 25-50 microliters/kg intravenously (i.v.) administered 1 day prior to near-lethal irradiation protected the regenerative capacity of the marrow, resulting in haematopoietic radioprotection and long-term survival of near-lethally-irradiated mice. In normal mice, Cremophor administration (1) markedly reduced the level of serum haematopoietic inhibitory activity 4-8 h following injection; (2) resulted in a transient decrease in femoral bone marrow cellularity and upregulated B220 (B cells), and 7/4 (neutrophils and activated macrophages), but not Thy-1 (T-cells) surface antigen expression in bone marrow cells within 24 h of injection; and (3) transiently elevated the incidence of both primitive and committed haematopoietic progenitor cells detected in clonal agar culture within 48 h of injection. Bone marrow progenitor cell content, and peripheral blood white cell, platelet and reticulocyte counts were unaffected. This suggests that the haematopoietic radioprotection and recovery observed in irradiated mice pretreated with Cremophor may be the result of accessory cell activation and/or modulation of accessory factors regulating haematopoietic progenitor cells. Our data suggest a potential clinical use of Cremophor as an adjunct to, or as a substitute for, cytokines to minimize myelosuppression following cytotoxic therapy.


Assuntos
Glicerol/análogos & derivados , Hematopoese/efeitos da radiação , Células-Tronco Hematopoéticas/efeitos da radiação , Contagem de Plaquetas/efeitos da radiação , Protetores contra Radiação/farmacologia , Contagem de Reticulócitos/efeitos da radiação , Animais , Medula Óssea/efeitos dos fármacos , Medula Óssea/efeitos da radiação , Células da Medula Óssea , Óleo de Rícino , Células Clonais , Ensaio de Unidades Formadoras de Colônias , Feminino , Citometria de Fluxo/métodos , Glicerol/farmacologia , Substâncias de Crescimento/farmacologia , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Interleucina-1/farmacologia , Interleucina-6/análise , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Contagem de Plaquetas/efeitos dos fármacos , Gravidez , Proteínas Recombinantes/farmacologia , Valores de Referência , Contagem de Reticulócitos/efeitos dos fármacos , Salmonella typhi , Fatores de Tempo
11.
Gen Comp Endocrinol ; 65(1): 79-86, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3803904

RESUMO

A radioimmunoassay was developed for salmonid melanin concentrating hormone (MCH) and used to measure immunoreactive (ir)MCH in the hypothalamus and pituitary of trout (Salmo gairdneri) and eels, (Anguilla anguilla) maintained under different regimes of background color. In trout, 95% of the total irMCH was located in the pituitary gland. The amount of MCH in both pituitary and hypothalamus was increased when white-adapted trout were transferred to a black background. In eels, a similar change of background led to an accumulation of MCH in the pituitary but not in the hypothalamus. The results suggest that MCH is released from the neurohypophysis in association with physiological color change. Neurointermediate lobes of trout and eels released both ir alpha MSH and irMCH when they were cultured in vitro. The release of alpha MSH was significantly enhanced when endogenous MCH was immunoabsorbed by MCH antiserum added to the culture medium. The results indicate that MCH can induce pallor in fish not only by its peripheral effect on the melanophores but also by an inhibitory action on the release of alpha MSH from the pituitary.


Assuntos
Anguilla/fisiologia , Hormônios Hipotalâmicos , Melaninas/farmacologia , Hormônios Estimuladores de Melanócitos/metabolismo , Hormônios Hipofisários/farmacologia , Salmonidae/fisiologia , Truta/fisiologia , Animais , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Técnicas In Vitro , Melaninas/fisiologia , Melanóforos/efeitos dos fármacos , Melanóforos/fisiologia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Hormônios Hipofisários/fisiologia , Pigmentação da Pele
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