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1.
Int J Appl Comput Math ; 7(4): 142, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34226872

RESUMO

In December 2019, a new outbreak in Wuhan, China has attracted world-wide attention, the virus then spread rapidly in most countries of the world, the objective of this paper is to investigate the mathematical modelling and dynamics of a novel coronavirus (COVID-19) with Caputo-Fabrizio fractional derivative in the presence of quarantine and isolation strategies. The existence and uniqueness of the solutions for the fractional model is proved using fixed point iterations, the fractional model are shown to have disease-free and an endemic equilibrium point.We construct a fractional version of the four-steps Adams-Bashforth method as well as the error estimate of this method. We have used this method to determine the numerical scheme of this model and Matlab program to illustrate the evolution of the virus in some countries (Morocco, Qatar, Brazil and Mexico) as well as to support theoretical results. The Least squares fitting is a way to find the best fit curve or line for a set of points, so we apply this method in this paper to construct an algorithm to estimate the parameters of fractional model as well as the fractional order, this model gives an estimate better than that of classical model.

2.
Case Rep Urol ; 2020: 8260191, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32509371

RESUMO

BACKGROUND: The association of renal cell carcinoma and Kartagener's syndrome is unusual, and only eleven cases have been reported in the literature. The purpose of this work is to analyze this unusual association of Kartagener's syndrome and renal cell tumor and to study the main diagnostic and therapeutic aspects through our observation and review of the literature. Case Presentation. We report the case of a 50-year-old patient, with a history of recurrent respiratory infections, in whom a renal tumor was simultaneously diagnosed with Kartagener's syndrome, represented by situs inversus, bronchiectasia, and chronic sinusitis. The patient was treated by partial nephrectomy, and the histological examination showed a clear cell carcinoma. Through this observation and a review of the literature, we try to analyze this association as well as the main diagnostic and therapeutic aspects. CONCLUSION: The association of situs inversus and renal cell carcinoma is very rare-preoperative assessment and anatomy knowledge are crucial for a better adaptation of the surgical technique.

3.
Pan Afr Med J ; 32: 110, 2019.
Artigo em Francês | MEDLINE | ID: mdl-31223400

RESUMO

This study aims to discuss the role of open surgery in the treatment of renal lithiasis, including coralliform stones, with the advent of new less invasive techniques. We report a series of 53 cases of coralliform stones whose data were collected in our Hospital during a period of 7 years, from January 2011 to January 2018. The patients underwent open nephrolithotomy by lombotomy. The mean post-operative length of stay was 10 days. The immediate and early postoperative outcomes were simple in 36 patients, 6 patients underwent blood transfusion, 2 had severe sepsis in the postoperative period, 5 had infection of the wall and 4 had urinary fistula, secondarily managed by endoscopic drainage. Residual stones were found in 9 cases (16.9%). Stones were essentially treated by extracorporeal lithotripsy. Late outcomes were characterized by renal atrophy in 2 patients, lithiasic recurrence in 9 patients, an improvement in creatinine clearance in 9 patients and a slight worsening in 5 patients. Open surgery presents the risk of multiple complications and it is not recommended for first-line treatment of renal lithiasis. However it is important to determine which patients would benefit from open nephrolithotomy.


Assuntos
Cálculos Renais/cirurgia , Litotripsia/métodos , Nefrolitotomia Percutânea/métodos , Complicações Pós-Operatórias/epidemiologia , Transfusão de Sangue/estatística & dados numéricos , Drenagem/métodos , Endoscopia/métodos , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Sepse/epidemiologia , Resultado do Tratamento , Fístula Urinária/epidemiologia
4.
Pan Afr Med J ; 30: 256, 2018.
Artigo em Francês | MEDLINE | ID: mdl-30637041

RESUMO

We here report the case of a 75 year old patient, with lower urinary tract obstructive syndrome such as dysuria, nocturnal pollakiuria and dribbling. Clinical examination showed good general condition by examining the rectum with the finger, soft, painless prostate increased in volume with obliteration of the median sulcus. PSA level was 2,1ng/ml, prostatic weight was 240 g on ultrasound. The patient underwent surgery: transvesical adenomectomy with extraction of a giant adenoma weighing 246 g. Histologic examination showed adenomyofibroma.


Assuntos
Adenoma/diagnóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Adenoma/cirurgia , Idoso , Humanos , Sintomas do Trato Urinário Inferior/etiologia , Masculino , Neoplasias da Próstata/cirurgia
5.
Neuroreport ; 28(16): 1049-1053, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-28902709

RESUMO

EM66 is a peptide derived from the chromogranin, secretogranin II (SG-II). Recent findings in mice indicate that EM66 is a novel anorexigenic neuropeptide that regulates hypothalamic feeding behavior, at least in part, by activating the POMC neurons of the arcuate nucleus. The present study aimed to investigate the mechanism of action of EM66 in the control of feeding behavior and, more specifically, its potential interactions with the NPY and POMC systems in rat. We analyzed by Q-PCR the gene expression of the EM66 precursor, SG-II, in hypothalamic extracts following 2, 3, or 4 days of food deprivation and compared it with the expression levels of the two major neuropeptidergic systems, that is, POMC and NPY, modulating feeding behavior. Our results show that fasting for 2 and 3 days has no effect on SG-II mRNA levels. However, 4 days of food deprivation induced a significant alteration in the expression levels of the three genes studied, with a significant increase in SG-II and NPY mRNAs, and conversely, a significant decrease in POMC mRNA. These data indicate that the EM66 gene expression is modulated by a negative energy status and suggest interactions between EM66 and NPY to regulate food intake through the POMC system.


Assuntos
Comportamento Alimentar/fisiologia , Privação de Alimentos , Hipotálamo/metabolismo , Neuropeptídeo Y/metabolismo , Pró-Opiomelanocortina/metabolismo , Secretogranina II/metabolismo , Animais , Comportamento Animal/fisiologia , Expressão Gênica/fisiologia , Masculino , Fragmentos de Peptídeos/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo
6.
Pan Afr Med J ; 26: 190, 2017.
Artigo em Francês | MEDLINE | ID: mdl-28674583

RESUMO

Scrotales fistulas are rare and often represent secondary lesions of tuberculosis. Mucinous adenocarcinomas are tumors containing at least 50% of extracellular mucus. They occur most commonly in the rectosigmoid; scrotal location is rare. We report the case of a 54-year old patient, with no particular past medical history, with secondary mucinous adenocarcinoma of the scrotum revealed by scrotal fistulas. The patient had suffered from recurrent scrotal fistulas for two years, with no other associated signs. Clinical examination showed multiple scrotal fistulas with discharge of thick pus. Rectal examination was normal. Urological examinations (IVU, UCRM, cystoscopy, …) were normal, the assessment of infectious diseases as well as the detection of BK virus in urine and sputum were negative. Biopsy of sample of scrotal tissue was in favor of moderately differentiated mucinous adenocarcinoma. Immunohistochemical examination was in favor of primary colorectal cancer. Patient's evolution was marked by the occurrence of complex anal fistulas, which appeared on MRI as active, supplying several pelvic peritoneal collections resulting in fleshy buds. There is no consensus on the therapeutic approach due to the rarity of this cancer. Surgical resection is the treatment of choice for this disease. Preoperative chemotherapy and radiation therapy are recommended for this type of cancer, but their role is not well established. The patient underwent primary neoadjuvant chemotherapy and radiation therapy, before abdominoperineal excision.


Assuntos
Adenocarcinoma Mucinoso/diagnóstico , Fístula/patologia , Neoplasias dos Genitais Masculinos/diagnóstico , Escroto/patologia , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/terapia , Neoplasias dos Genitais Masculinos/patologia , Neoplasias dos Genitais Masculinos/terapia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
7.
Pan Afr Med J ; 24: 17, 2016.
Artigo em Francês | MEDLINE | ID: mdl-27583081

RESUMO

Deep dorsal penile vein thrombosis (DDPVT)is a rare and little known urologic emergency. It requires an early etiological and symptomatic approach to preserve erectile function and prevent recurrences. This study reports a case of dorsal penile vein thrombosis revealed by spontaneous priapism that didn't resolve adequately and confirmed by penile Doppler ultrasound. After management of priapism and DDPVT, the etiological investigation revealed Behcet's disease whose diagnosis was based on the association of a major criteria, such as oral aphthous ulcers with 3 minor criteria such as: genital aphthous ulcers, ocular involvement, and a positive skin pathergy test within 24h. The patient underwent etiological treatment with good clinical evolution and preservation of erectile function.


Assuntos
Síndrome de Behçet/diagnóstico , Doenças do Pênis/etiologia , Priapismo/etiologia , Trombose Venosa/etiologia , Síndrome de Behçet/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Pênis/diagnóstico por imagem , Pênis/irrigação sanguínea , Estomatite Aftosa/etiologia , Ultrassonografia Doppler/métodos , Trombose Venosa/diagnóstico por imagem
8.
Neurotoxicology ; 49: 165-73, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26141519

RESUMO

The presence of mycotoxins in food is a major problem of public health as they produce immunosuppressive, hepatotoxic and neurotoxic effects. Mycotoxins also induce mutagenic and carcinogenic effects after long exposure. Among mycotoxins that contaminate food are aflatoxins (AF) such as AFB1, which is the most powerful natural carcinogen. The AF poisoning results in symptoms of depression, anorexia, diarrhea, jaundice or anemia that can lead to death, but very few studies have explored the impact of AF on neuroendocrine regulations. To better understand the neurotoxic effects of AF related to anorexia, we explored in rat the impact of AFB1 on the major hypothalamic neuropeptides regulating feeding behavior, either orexigenic (NPY, Orexin, AgRP, MCH) or anorexigenic (α-MSH, CART, TRH). We also studied the effect of AFB1 on a novel neuropeptide, the secretogranin II (SgII)-derived peptide EM66, which has recently been linked to the control of food intake. For this, adult male rats were orally treated twice a week for 5 weeks with a low dose (150 µg/kg) or a high dose (300 µg/kg) of AFB1 dissolved in corn oil. Repeated exposure to AFB1 resulted in reduced body weight gain, which was highly significant for the high dose of AF. Immunocytochemical and quantitative PCR experiments revealed a dose-related decrease in the expression of all the hypothalamic neuropeptides studied in response to AFB1. Such orexigenic and anorexigenic alterations may underlie appetite disorders as they are correlated to a dose-dependent decrease in body weight gain of treated rats as compared to controls. We also found a decrease in the number of EM66-containing neurons in the arcuate nucleus of AFB1-treated animals, which was associated with a lower expression of its precursor SgII. These findings show for the first time that repeated consumption of AFB1 disrupts the hypothalamic regulation of neuropeptides involved in feeding behavior, which may contribute to the lower body weight gain associated to AF exposure.


Assuntos
Aflatoxina B1/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Neuropeptídeos/metabolismo , Venenos/farmacologia , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Neuropeptídeos/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar
9.
Regul Pept ; 182: 28-34, 2013 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-23333484

RESUMO

EM66 is a secretogranin II-derived peptide strongly expressed within hypothalamic neuroendocrine areas such as the parvocellular aspect of the paraventricular nucleus (pPVN) as well as the median eminence (ME), suggesting a hypophysiotropic role for this neuropeptide. The aim of the present study was to explore such a role in the corticotrope and thyrotrope axes. We analyzed EM66 occurrence respectively in CRH and TRH neurosecretory cells of the rat pPVN by double immunohistochemistry. Functionally, we studied the effect of acute stress (immobilization for 2 h or cold exposure at 5°C for 4 h) and hypothyroidism (induced by 1-week thyroidectomy) on EM66 immunoreactivity (IR) within the pPVN. Double immunohistochemical labeling revealed that EM66-IR colocalized with CRH or TRH labelings within pPVN hypophysiotropic neurons as well as the axon terminals of the external layer of the ME. Because TRH neuronal population of the pPVN is completely distinct from the CRH neurosecretory system, our data demonstrate the existence of at least two distinct EM66 neuronal populations in the rat pPVN. Acute immobilization or cold exposure stresses did not affect EM66 expression as evaluated by the number of EM66-IR neurons within the pPVN. These results suggest that EM66 does not participate to the phenotypic plasticity of hypothalamic parvocellular neurons in response to acute stress. In addition, short-term hypothyroidism did not provoke any significant variation of the number of intraparaventricular EM66 neurons, indicating that EM66 expression would be insensitive to short-term hypothyroidism despite its occurrence within TRH neurons. Thus, the present data show the occurrence of EM66 in distinct areas of the rat PVN but its expression is not coregulated with those of CRH and TRH during acute stress and hypothyroidism.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Secretogranina II/farmacologia , Estresse Fisiológico , Tireoidectomia , Hormônio Liberador de Tireotropina/metabolismo , Animais , Imuno-Histoquímica , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Núcleo Hipotalâmico Paraventricular/citologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Ratos , Ratos Wistar
10.
Neuro Endocrinol Lett ; 31(5): 609-15, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21173750

RESUMO

OBJECTIVES AND METHODS: Neuropeptides, as the main neuroendocrine system effectors, regulate notably the response to different stressors via a secretory plasticity within their respective hypothalamic neuronal populations. The aim of the present study was to explore by immunocytochemistry the occurrence and the potential expression plasticity of the novel neuropeptide EM66 in the CRH neurones of stressed rats. RESULTS: The secretogranin II (SgII)-derived peptide EM66 is strongly expressed within hypothalamic neuroendocrine areas such as the parvocellular aspect of the paraventricular nucleus (pPVN) as well as the median eminence, suggesting a probable hypophysiotropic effect of this peptide. As a first approach to investigate such a role, we evaluated by immunohistochemistry EM66 expression within the pPVN following acute immune stress induced by lipopolysaccharide (LPS) or interleukin-1ß (IL-1ß) injection in rat. This study showed that EM66 is present in the pPVN but the number of EM66 immunolabeled cells did not fluctuate in this structure following LPS peripheral injection. In line with this observation, an intracerebroventricular injection of IL-1ß did not provoke any significant variation of the number of intraparaventricular EM66 neurones. CONCLUSION: The present data revealed for the first time that EM66 expression would be insensitive to the central and peripheral cytokines within the neurosecretory hypothalamic pPVN. This result indicates that EM66 does not participate to the phenotypic plasticity of hypothalamic parvicellular neurones in response to acute inflammatory stress.


Assuntos
Plasticidade Neuronal , Neuropeptídeos/biossíntese , Núcleo Hipotalâmico Paraventricular/metabolismo , Fragmentos de Peptídeos/metabolismo , Secretogranina II/metabolismo , Estresse Fisiológico , Animais , Modelos Animais de Doenças , Imuno-Histoquímica , Injeções Intraperitoneais , Injeções Intraventriculares , Interleucina-1beta , Lipopolissacarídeos , Masculino , Núcleo Hipotalâmico Paraventricular/imunologia , Fragmentos de Peptídeos/imunologia , Ratos , Ratos Wistar , Secretogranina II/química , Secretogranina II/imunologia , Estresse Fisiológico/imunologia
11.
Neuro Endocrinol Lett ; 29(4): 547-51, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18766146

RESUMO

OBJECTIVES AND METHODS: The presence of oxytocin (OT) and its putative participation to the phenotypic plasticity of CRH neurones in the stressed jerboa was investigated. We analysed by immunocytochemistry the OT expression within the hypothalamic parvicellular paraventricular nucleus (pPVN) of male jerboas submitted to an acute immobilization (30 min). RESULTS: OT presence was clearly demonstrated in the pPVN of the jerboa and no significant difference in the number of OT immunolabeled cells was observed whatever the experimental conditions. Interestingly, CRH-immunoreactive neurons coexpressed OT within cell bodies and terminals in a similar way both in control and stressed animals. The level of coexpression was regionally heterogeneous and was not sensitive to the stress immobilization. CONCLUSION: The present data reveal for the first time the occurrence of OT in hypothalamic pPVN neurons of the jerboa. Moreover, this OT expression level does not change upon an acute immobilization stress. These new data, coupled together with our previous work in the jerboa, incontestably establish a clear dichotomy between a stress-responsive CRH/CCK system and a stress non-responsive OT/VP system in the pPVN.


Assuntos
Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Ocitocina/metabolismo , Núcleo Hipotalâmico Paraventricular/citologia , Restrição Física , Roedores , Estresse Psicológico , Animais , Feminino , Masculino , Neurônios/citologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Ratos
12.
Neurosci Lett ; 414(3): 268-72, 2007 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-17240057

RESUMO

EM66 is a 66-amino acid peptide derived from secretogranin II, a member of granin acidic secretory protein family, by proteolytic processing. EM66 has been previously characterized in the jerboa (Jaculus orientalis) hypothalamus and its potential implication in the neuroendocrine regulation of feeding behaviour has been demonstrated. In the present study, an immunohistochemical analysis of the localization of EM66 within hypothalamic structures of rat was performed and compared to the distribution of EM66 in the jerboa hypothalamus. In the rat hypothalamus, as in the jerboa, EM66 immunostaining was detected in the parvocellular paraventricular, preoptic and arcuate nuclei, as well as the lateral hypothalamus which displayed an important density of EM66-producing neurones. However, unlike jerboa, the suprachiasmatic and supraoptic nuclei of the rat hypothalamus were devoid of cellular EM66-immunolabeling. Thus, the novel peptide EM66 may exert common neuroendocrine activities in rat and jerboa, e.g. control of food intake, and species-specific roles in jerboa such as the regulation of biological rhythms and hydromineral homeostasis. These results suggest the existence of differences between jerboas and rats in neuroendocrine regulatory mechanisms involving EM66.


Assuntos
Hipotálamo/metabolismo , Neuropeptídeos/metabolismo , Fragmentos de Peptídeos/metabolismo , Ratos Wistar/metabolismo , Roedores/metabolismo , Secretogranina II/metabolismo , Animais , Mapeamento Encefálico , Comportamento Alimentar/fisiologia , Feminino , Homeostase/fisiologia , Hipotálamo/anatomia & histologia , Imuno-Histoquímica , Masculino , Neurônios/metabolismo , Neuropeptídeos/química , Sistemas Neurossecretores/metabolismo , Fragmentos de Peptídeos/química , Periodicidade , Ratos , Ratos Wistar/anatomia & histologia , Roedores/anatomia & histologia , Secretogranina II/química , Especificidade da Espécie , Equilíbrio Hidroeletrolítico/fisiologia
13.
Neuroendocrinology ; 76(4): 243-53, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12411741

RESUMO

Dehydration, a classic homeostatic stressor in rats, leads to a series of well characterized endocrine responses including stimulation of the hypothalamo-pituitary-adrenal (HPA) axis. In this study, the hypothesis to be tested was that a 50% maternal food restriction (FR50) in late gestation and lactation may have long-term repercussions on HPA axis responsiveness to dehydration in offspring. For this purpose, we studied HPA axis activity in 4-month-old control (C) and perinatally malnourished male rats after a 72-hour water deprivation period. Furthermore, we investigated the long-lasting effects of perinatal maternal malnutrition on the basal activity of the HPA axis. Under basal conditions, rats exposed to perinatal malnutrition showed reduced body weight, enhanced mineralocorticoid receptor (MR) mRNA levels in CA2 and CA3 hippocampal areas, but decreased glucocorticoid receptor (GR) mRNA levels in CA1, CA3 and dentate gyrus (DG) areas. In contrast, the levels of corticotropin-releasing hormone (CRH) and vasopressin (VP) mRNAs in the hypothalamic paraventricular nucleus (PVN) as well as of VP mRNA in the supraoptic nucleus (SON) were unaffected by maternal undernutrition. Expression of proopiomelanocortin (POMC) in the adenohypophysis was significantly enhanced, whereas prohormone convertase-1 (PC1) was not affected. Perinatal malnutrition reduced absolute adrenal weight but did not affect circulating levels of adrenocorticotropin (ACTH), corticosterone and free corticosterone as well as corticosteroid-binding globulin (CBG) binding capacity. Seventy-two hours of dehydration induced a decrease in body weight and CRH mRNA levels in PVN of controls as well as of FR50 rats, but also led to a rise in plasma corticosterone and free corticosterone without changing CBG binding capacity. Dehydration also induced an increase in adenopituitary POMC (C) and PC1 (FR50), PVN and SON VP (C) and GR in CA1 hippocampal area (FR50) mRNA levels and plasma ACTH (C), but a decrease in MR in DG (C) and GR in CA3 and DG (C) mRNA levels. We conclude that maternal food restriction during the perinatal period affects (1) the adult basal activity of the HPA axis with mainly opposite effects on hippocampal MR and GR gene expression and an increase in adenopituitary POMC gene expression, and (2) the responsiveness to water deprivation in adults. In the latter case, the rise in plasma ACTH levels, adenopituitary POMC gene expression, hypothalamic VP gene expression, and the decrease in hippocampal MR gene expression in DG and GR gene expression in CA3 and DG observed in controls are lacking in FR50 rats. In contrast, drastic adenopituitary PC1 gene expression occurred in FR50 rats but not in control animals.


Assuntos
Animais Recém-Nascidos/fisiologia , Desidratação/fisiopatologia , Privação de Alimentos/fisiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal , Glândulas Suprarrenais/patologia , Animais , Ácido Aspártico Endopeptidases/metabolismo , Sangue/metabolismo , Peso Corporal/fisiologia , Feminino , Hormônios/metabolismo , Hipotálamo/metabolismo , Masculino , Tamanho do Órgão , Adeno-Hipófise/metabolismo , Gravidez , Pró-Opiomelanocortina/metabolismo , Pró-Proteína Convertases , Ratos , Ratos Wistar , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides , Transcortina/metabolismo , Vasopressinas/metabolismo
14.
Eur J Endocrinol ; 147(6): 835-48, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12457460

RESUMO

OBJECTIVE: The first aim of this work was to investigate, under basal conditions in adult male rats, the long-term consequences of perinatal maternal food restriction on the plasma concentrations of vasopressin (VP), aldosterone and atrial natriuretic peptide (ANP) and on plasma renin activity (PRA). Furthermore, under these same conditions, the hypothalamic VP gene expression as well as the density (B(max)), affinity (K(d)) and gene expression of ANP receptors were determined in kidneys and adrenals. The second aim of this work was to examine the responsiveness to dehydration in perinatally malnourished rats. Thus, the latter parameters were studied in these rats after 72 h water deprivation. METHODS: This study was conducted on 4-Month-old male rats from mothers exposed to 50% food restriction (FR50) during the last week of gestation and lactation and on age-matched control animals (C). At this stage, both C and FR50 rats were killed by decapitation between 0900 h and 1000 h in order to determine parameters under basal conditions or after 72 h water deprivation. Plasma VP, ANP and aldosterone levels and PRA were determined by radioimmunoassay. Hypothalamic VP gene expression was determined in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) by in situ hybridization. The B(max) and K(d) values of ANP receptors were evaluated from Scatchard plots. ANP receptor gene expression was determined by Northern blot analysis. RESULTS: Under basal conditions, perinatal malnutrition reduced body weight, absolute weight of kidneys and adrenals, and haematocrit. Compared with control rats, FR50 rats had significantly greater plasma VP and aldosterone levels but PRA, plasma ANP levels, plasma osmolality and hypothalamic VP gene expression were not significantly different. Perinatal malnutrition did not significantly affect glomerular ANP receptor density, but in adrenals it decreased both B(max) and K(d) values of ANP-B receptors (biological receptors) and increased B(max) of ANP-C receptors (clearance receptors). ANP-B(A) (receptor subtype A of ANP-B receptors) receptor gene expression was not significantly affected, whereas ANP-C receptor gene expression was enhanced in both adrenals and kidneys in FR50 rats. After 72 h dehydration, control rats showed a significant rise in haematocrit, plasma osmolality, PRA, circulating levels of VP and aldosterone and VP gene expression in both PVN and SON but showed a decrease in plasma ANP levels. B(max) of ANP-B receptors was decreased whereas B(max) of ANP-C receptors was enhanced in both adrenals and kidneys. ANP-B(A) receptor gene expression was not significantly affected in either kidneys or adrenals in dehydrated control rats. Similarly, ANP-C receptor gene expression was unaffected in kidneys whereas it was significantly enhanced in adrenals. In FR50 rats, the effects of water deprivation were qualitatively similar to those reported in controls concerning plasma parameters except for plasma VP levels which tended to rise (not significant) but this increase was only very slight compared with controls. Moreover, unlike controls, VP gene expression in both PVN and SON was not enhanced after dehydration in FR50 rats. In kidneys, dehydrated FR50 rats, like controls, upregulated ANP-C receptors, but they were unable to downregulate ANP-B receptors. In adrenals, unlike controls, FR50 rats enhanced ANP-B receptor density whereas they decreased both ANP-C receptor density and expression after 72 h dehydration. Similar to controls, the expression of ANP-B(A) receptors in both kidneys and adrenals as well as the expression of ANP-C receptors in kidneys, were unaffected in dehydrated FR50 rats. CONCLUSION: Perinatal malnutrition had long-lasting effects on regulation of the fluid and electrolyte balance under basal conditions. The main effects were a significant rise in circulating levels of VP and aldosterone, and changes in density of adrenal ANP-binding sites and ANP-C receptor gene expression in both adrenals and kidneys. Perinatal malnutrition also affects the responsiveness to water deprivation with alterations in both hypothalamic VP gene expression and regulation of ANP-binding sites.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Desidratação/fisiopatologia , Glândulas Endócrinas/fisiopatologia , Distúrbios Nutricionais/fisiopatologia , Equilíbrio Hidroeletrolítico , Glândulas Suprarrenais/metabolismo , Animais , Animais Recém-Nascidos/fisiologia , Fator Natriurético Atrial/metabolismo , Sítios de Ligação , Peso Corporal , Desidratação/complicações , Desidratação/metabolismo , Embrião de Mamíferos/fisiologia , Hormônios/sangue , Hipotálamo/metabolismo , Rim/metabolismo , Masculino , Distúrbios Nutricionais/sangue , Distúrbios Nutricionais/complicações , Distúrbios Nutricionais/patologia , Tamanho do Órgão , Ratos , Ratos Wistar , Receptores do Fator Natriurético Atrial/metabolismo , Distribuição Tecidual , Vasopressinas/metabolismo
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