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1.
Curr Psychol ; 42(9): 7797-7811, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36406839

RESUMO

Parents play a critical role in emotional socialization and the development of emotion regulation during childhood. The tools to measure how parents assist children's emotion regulation are very limited. The Parental Assistance with Child Emotion Regulation (PACER) Questionnaire is a novel scale developed for this purpose with excellent psychometric properties. The aim of this study is to adapt the PACER to Turkish and investigate its psychometric properties in the Turkish cultural setting. The data were collected from 700 parents who have children aged birth to 17 years. In addition to the PACER, participants filled out some scales about their own beliefs and behaviors, also their children's psychological symptoms. We confirmed the original ten-factor structures of the PACER in a Turkish sample and the measurement invariance supported the PACER's structure across subgroups. The high internal consistencies of factors were achieved; however, the test-retest reliability was lower than expected. The factors of maladaptive emotion regulation strategies (e.g., rumination, expressive suppression, avoidance) were positively associated with parents' own emotion regulation deficit, symptoms, and child's symptoms, while others (e.g., reappraisal, problem-solving) were negatively associated with them. Overall, our results suggest that the Turkish version of the PACER is a psychometrically valid and reliable measurement to assess how parents support their children to regulate their emotions. We believe that this adaptation allows the scale to be used in developmental and clinical psychology studies and will pave the way for cross-cultural studies.

2.
Dev Psychol ; 49(3): 579-90, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22946437

RESUMO

Research on preschoolers' selective learning has mostly been conducted in English-speaking countries. We compared the performance of Turkish preschoolers (who are exposed to a language with evidential markers), Chinese preschoolers (known to be advanced in executive skills), and English preschoolers on an extended selective trust task (N = 144). We also measured children's executive function skills and their ability to attribute false belief. Overall we found a Turkish (rather than a Chinese) advantage in selective trust and a relationship between selective trust and false belief (rather than executive function). This is the 1st evidence that exposure to a language that obliges speakers to state the sources of their knowledge may sensitize preschoolers to informant reliability. It is also the first demonstration of an association between false belief and selective trust. Together these findings suggest that effective selective learning may progress alongside children's developing capacity to assess the knowledge of others.


Assuntos
Desenvolvimento Infantil/fisiologia , Comparação Transcultural , Função Executiva/fisiologia , Aprendizagem/fisiologia , Percepção Social , Confiança/psicologia , Pré-Escolar , China/etnologia , Formação de Conceito/fisiologia , Inglaterra/etnologia , Humanos , Inibição Psicológica , Conhecimento , Idioma , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos , Turquia/etnologia
3.
Acta Physiol (Oxf) ; 190(4): 351-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17394566

RESUMO

AIM: The study of kinematics of the chest wall (CW) could allow us to define the relative deflationary contribution of its compartments during fits of coughing. We hypothesized that if forces applied to the lung apposed rib cage are not commensurate with those applied to the abdomen-apposed rib cage, cough could result in rib cage distortion. METHODS: In 12 (five women) healthy subjects we evaluated the volumes of CW (Vcw) and its compartments: the lung apposed rib cage, the abdomen apposed rib cage and the abdomen, by optoelectronic plethysmography. The loop of volume of the lung apposed rib cage/volume of the abdomen apposed rib cage allowed the calculation of mean rib cage distortion, resulting in a dimensionless number which, when multiplied by 100, gives percentage distortion. Each subject performed voluntary single and prolonged coughing efforts at functional residual capacity (FRC) and after maximal inspiration (max). The normal level of mean distortion was set at <0.5%. RESULTS: The three compartments contributed to reducing end-expiratory Vcw during cough at FRC and prolonged maximum cough, with the latter resulting in the greatest CW deflation. Mean rib cage distortion did not differ between men and women (P > 0.1), but tended to significantly increase from single to prolonged Cough Max (1.3% +/- 1.0 vs. 2.3% +/- 1.6, respectively; P = 0.06). CONCLUSION: Rib cage distortion may ensue during coughing, probably as a result of uneven distribution of forces applied to the rib cage.


Assuntos
Tosse/fisiopatologia , Costelas/fisiopatologia , Parede Torácica/fisiologia , Adulto , Fenômenos Biomecânicos , Tosse/patologia , Feminino , Humanos , Masculino , Pletismografia , Mecânica Respiratória/fisiologia , Costelas/patologia , Parede Torácica/patologia
4.
Mutat Res ; 474(1-2): 139-46, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11239971

RESUMO

Stable and unstable chromosome aberrations in human lymphocytes exposed to 2 and 4Gy of X-rays in G(0) were analyzed in M1 and M2 cells harvested at 72h to investigate how the scoring protocol influences the yields of aberrations transmitted through one mitosis. Metaphase chromosomes 2, 3, and 5 were painted using fluorescence in situ hybridization (FISH) whole chromosome probes, together with a pan-centromeric probe and stained by the harlequin-FISH method, to allow the cell cycle status of each cell to be determined as it was scored. A strict scoring criterion was adopted so that each metaphase had to contain 46 centromeres and each dicentric/centric ring had to have an acentric present. In addition to scoring the painted material, unstable aberrations in the whole genome were also recorded. The yield of complete dicentrics decreased by more than a factor of 2 in going from M1 to M2. The decrease was greater at the lower dose. Two-way translocations appeared stable, but one-way translocations decreased. This suggests that if translocation yields are to be used for biological dosimetry purposes, then the two-way type should be used.


Assuntos
Aberrações Cromossômicas , Linfócitos/ultraestrutura , Mitose/genética , Adulto , Feminino , Humanos , Hibridização in Situ Fluorescente , Linfócitos/efeitos da radiação
5.
Am J Hypertens ; 12(10 Pt 1): 1000-8, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10560786

RESUMO

We investigated the effects of transdermal 17beta-estradiol, combined with standard antihypertensive therapy, on the modification of the cardiovascular risk profile in hypertensive postmenopausal women. In a randomized, double-blind, placebo-controlled study, we enrolled 200 postmenopausal women with mild to moderate hypertension. Patients received 17beta-estradiol (50 microg/day, transdermal) and norethisterone acetate (2.5 mg/ day, orally) or placebo. At baseline serum total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, glucose, and fibrinogen plasma levels were measured and all subjects underwent complete M-mode and 2-D echocardiograms, which were repeated after 6, 12, and 18 months of hormonal replacement therapy. Compared with placebo, all values decreased significantly except for HDL cholesterol. In both groups, no modifications were observed in echocardiographic parameters, except for left ventricular mean diastolic and systolic wall thickness and left ventricular mass index, which showed a significant decrease in both groups. The reduction was greater in the treated group; the percentage of patients with left ventricular hypertrophy was 46% before randomization and 17.2% after 18 months of treatment (P < .0001), whereas in group II the percentage was 48% at baseline and 31.5% after 18 months (P < .05). In conclusion, transdermal 17beta-estradiol, associated with antihypertensive therapy, may contribute to the reduction of cardiovascular risk profile in hypertensive postmenopausal women.


Assuntos
Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios , Hipertensão/fisiopatologia , Administração Cutânea , Adulto , Idoso , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Método Duplo-Cego , Feminino , Humanos , Hipertensão/sangue , Hipertrofia Ventricular Esquerda/prevenção & controle , Pessoa de Meia-Idade , Pós-Menopausa
6.
Mutat Res ; 359(2): 151-7, 1996 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-8598833

RESUMO

Dose-response for micronuclei in cytokinesis-blocked lymphocytes after in vitro irradiation of whole blood from 3 donors with Co-60 gamma-rays in the range 0-5.0 Gy was established. The numerical relationship between radiation induced chromosomal aberrations, and micronuclei is also examined. An increased frequency of micronuclei following low doses of gamma-irradiation is reported from a study of 41 radiation workers.


Assuntos
Linfócitos/efeitos da radiação , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Adulto , Aberrações Cromossômicas , Radioisótopos de Cobalto , Relação Dose-Resposta à Radiação , Feminino , Raios gama , Humanos , Linfócitos/ultraestrutura , Masculino , Exposição Ocupacional , Monitoramento de Radiação
7.
Mutat Res ; 329(1): 57-61, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7770076

RESUMO

A dose-response curve has been obtained for the induction of chromosome aberrations in human lymphocytes from blood acutely irradiated with 60Co gamma-rays in a dose range of 0.098-4.89 Gy. This curve has been used for biological dose estimation for 21 cases of known or suspected accidental overexposure of Turkish radiation workers.


Assuntos
Aberrações Cromossômicas , Raios gama , Monitoramento de Radiação/métodos , Liberação Nociva de Radioativos , Adulto , Carga Corporal (Radioterapia) , Radioisótopos de Cobalto/efeitos adversos , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Exposição Ocupacional/efeitos adversos , Turquia
8.
Clin Exp Hypertens ; 15 Suppl 1: 187-96, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8513309

RESUMO

We compared the response of blood pressure (BP) to either K-Canrenoate (K-Can) or hydrochlorothiazide (HCTZ) in 26 mild-to-moderate essential hypertensives in a double-blind, cross-over design over 2 months each. The dose was 12.5 mg o.d. for HCTZ and 50 mg o.d. for K-Can: dosing was doubled after 1 month if seated diastolic BP was > or = 95 mmHg. Eight pts were "selective responder" to the lowest dose of HCTZ (HCTZ-R), and 6 to K-Can (K-Can-R). Seven pts had their high blood pressure controlled by the highest dose of both drugs and 4 were insensitive to both. One pt dropped out during HCTZ for low plasma K+, and 3 during K-Can (nausea and dizziness: 2 pts; plasma creatinine rise: 1 pt). All these side effects were reverted after drug withdrawal. HCTZ-R and K-Can-R differed for PRA (1.4 +/- 0.6 vs 0.8 +/- 0.4 Ang I ng/ml/h, p < 0.05) and Na-K-Cl cotransport (230 +/- 39 vs 372 +/- 24 mumolNa/L RBC/h, p < 0.01). Our data suggest the existence of a subgroup of essential hypertensives surprisingly insensitive to HCTZ, characterized by a "low" PRA and by a Na(+)-K(+)-Cl- cotransport higher than the HCTZ-R. Their selective response to K-Can suggest a peculiar pathogenetic mechanism underlying their high blood pressure.


Assuntos
Ácido Canrenoico/uso terapêutico , Hidroclorotiazida/uso terapêutico , Hipertensão/tratamento farmacológico , Pressão Sanguínea/efeitos dos fármacos , Ácido Canrenoico/efeitos adversos , Método Duplo-Cego , Resistência a Medicamentos , Feminino , Humanos , Hidroclorotiazida/efeitos adversos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Potássio/sangue
10.
J Cardiovasc Pharmacol ; 18(3): 462-7, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1720847

RESUMO

Angiotensin II was reported to play a key role in ovulation in rats and it seems also to be involved in the regulation of LH release. Thus, we studied the effect of chronic ACE inhibition on the menstrual cycle, measuring daily plasma estradiol, progesterone, LH and FSH, and renin and prorenin before and during the third month of treatment with enalapril (10 mg b.i.d.) in 10 mild essential hypertensive women. Blood pressure was normalized by treatment. The cyclical changes of steroids and gonadotrophins were unaffected in their temporal relationships and in the magnitude of their variation during the experimental cycle compared with the basal cycle. A synchronization of plasma prorenin with the other hormones was seen both before, as previously reported, and during enalapril treatment. Our data show that peripheral blockade of angiotensin I conversion does not affect the pituitary guidance of the ovarian hormonal response or the ovarian prorenin release during the menstrual cycle. Our data are in agreement with the hypothesis that circulating angiotensin II does not play a key role in the human fertility process and that hydrophilic ACE inhibitors can be safely used in the treatment of hypertensive women of reproductive age.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Hipertensão/complicações , Ciclo Menstrual/efeitos dos fármacos , Adulto , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Angiotensinogênio/sangue , Pressão Sanguínea/efeitos dos fármacos , Eletrólitos/urina , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/sangue , Humanos , Hipertensão/tratamento farmacológico , Hormônio Luteinizante/sangue , Progesterona/sangue , Renina/sangue
11.
Can J Physiol Pharmacol ; 69(9): 1394-7, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1756445

RESUMO

We looked for the presence of prorenin in erythrocytes from normal subjects (n = 8), hypertensive patients (n = 8), and pregnant women (n = 8). Angiotensin I generation was measured at 37 degrees C, pH 5.7, in the presence of homologous substrate (1400 ng/mL) before and after trypsin activation (100 micrograms/mL) in (A) haemolyzed erythrocytes, (B) supernatants of haemolyzed erythrocytes, and (C) in the sixth washing of erythrocytes diluted 1:1 with a 0.1 M Tris buffer containing 0.5% bovine serum albumin and protease inhibitors. Haemolyzed erythrocytes generated angiotensin I only after trypsin treatment, and the rate of generation was the same (A) before and (B) after centrifugation at 20,000g, indicating the absence of prorenin bound to the cell membranes. When aliquots of the last washing of erythrocytes (C) were tested for angiotensin I generation before and after trypsin, they did not generate angiotensin I, indicating that residual prorenin from the plasma was no longer present in our preparation. Angiotensin I generation by trypsin-treated A and B was completely abolished by preincubation with anti-renin serum. The level of prorenin was not significantly different in the erythrocytes from normal, hypertensive, and pregnant subjects (68 +/- 10, 58 +/- 7 and 107 +/- 17 pg angiotensin I.mL-1.h-1, ns) in spite of their very different plasma levels (21 +/- 2.5, 17 +/- 2.4 and 110 +/- 12 ng angiotensin I.mL-1.h-1, p less than 0.01 for pregnant women compared with both normal and hypertensive subjects). Our data show that prorenin is present in human erythrocytes in fairly constant and clearly detectable amounts, thus suggesting a possible intracellular role for it.


Assuntos
Precursores Enzimáticos/sangue , Eritrócitos/enzimologia , Hipertensão/enzimologia , Renina/sangue , Adulto , Feminino , Humanos , Masculino , Gravidez
12.
Boll Soc Ital Biol Sper ; 66(7): 663-70, 1990 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-2083060

RESUMO

Since angiotensin II seems to be involved in the process of ovulation we studied the effect of chronic enalapril on plasma prorenin, renin, estradiol, progesterone, LH and FSH during the menstrual cycle in ten essential hypertensive women. Our data show that peripheral blockade of A I conversion does not affect the pituitary guidance and the ovarian hormonal response of the menstrual cycle and, we can speculate, that it does not interfere with the process of ovulation.


Assuntos
Enalapril/farmacologia , Precursores Enzimáticos/sangue , Hormônios Esteroides Gonadais/sangue , Hipertensão/tratamento farmacológico , Ciclo Menstrual/efeitos dos fármacos , Renina/sangue , Adulto , Angiotensina II/fisiologia , Enalapril/uso terapêutico , Feminino , Humanos , Hipertensão/fisiopatologia , Ovulação/efeitos dos fármacos , Adeno-Hipófise/efeitos dos fármacos , Adeno-Hipófise/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos
13.
Boll Soc Ital Biol Sper ; 66(7): 671-8, 1990 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-2083061

RESUMO

We studied the effect of nifedipine, a dihydropyridine calcium antagonist, on the hemodynamic changes induced by endothelin, in awake normotensive rats. Endothelin (0.07-1.40 nmol/kg, e.v.) caused an initial hypotensive effect, followed by long lasting hypertension. Renal blood flow was reduced immediately and still remained below basal levels, at 30 minutes after endothelin injection. Nifedipine (1 mg/kg, i.p.) significantly prevented the effect of endothelin on mean blood pressure and induced a right-ward shift in the dose response curve of renal hemodynamic changes induced by endothelin. We conclude that treatment with calcium antagonist could be very useful in all those conditions in which systemic and regional vasocostriction is provoked by endothelin.


Assuntos
Endotelinas/antagonistas & inibidores , Nifedipino/farmacologia , Circulação Renal/efeitos dos fármacos , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Endotelinas/farmacologia , Masculino , Ratos , Ratos Endogâmicos , Artéria Renal/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos
14.
Boll Soc Ital Biol Sper ; 66(7): 679-84, 1990 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-1964565

RESUMO

Erythrocyte cation transport, plasma prorenin and renin and sexual hormones were sequentially evaluated in 12 normal volunteers over the menstrual cycle. Na-K cotransport and Na-Li countertransport raised in 6 out of 12 subjects in synchronization with the ovulatory phase. When the maximal % variation (ovulatory phase) versus baseline (follicular phase) of the Na-K cotransport was plotted versus the maximal % increment of oestrogens. A direct, highly significant inverse correlation was observed (r = 0.904, p less than 0.001). Moreover, a highly significant inverse correlation between plasma prorenin and intraerythrocyte Na (r = -0.857, p less than 0.001) in the follicular phase was found. Our data suggest that erythrocyte cation transport can be influenced by sexual hormones in human.


Assuntos
Membrana Eritrocítica/metabolismo , Hormônios Esteroides Gonadais/sangue , Lítio/metabolismo , Ciclo Menstrual/fisiologia , Potássio/metabolismo , Sódio/metabolismo , Adulto , Transporte Biológico/efeitos dos fármacos , Precursores Enzimáticos/sangue , Feminino , Humanos , Renina/sangue , ATPase Trocadora de Sódio-Potássio/metabolismo
15.
J Hypertens Suppl ; 7(6): S238-9, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2534409

RESUMO

Plasma atrial natriuretic factor (ANF), blood pressure, age, plasma renin activity and creatinine were measured in 50 normal volunteers, 141 essential hypertensives, 35 patients with chronic renal failure who had never been dialysed and 27 patients with end-stage renal failure on constant haemodialysis. Plasma ANF was correlated positively with age in the normal group (r = 0.52, P less than 0.01) and with blood pressure in the essential hypertensives (r = 0.50, P less than 0.001), and negatively with renin in the normal and end-stage renal failure patients (r = -0.47, r = -0.34; P less than 0.01, P less than 0.05, respectively). When patients without left ventricular hypertrophy were matched for age and blood pressure, plasma ANF was significantly different between the essential hypertensives and the normal and end-stage renal failure patients (16 +/- 1, 38 +/- 6 and 148 +/- 24 pmol/l, respectively; P less than 0.001). Cardiac factors are therefore not the only determinant of circulating plasma ANF in humans with chronic renal failure.


Assuntos
Fator Natriurético Atrial/sangue , Falência Renal Crônica/sangue , Envelhecimento/fisiologia , Pressão Sanguínea/fisiologia , Creatinina/sangue , Humanos , Rim/fisiopatologia , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Diálise Renal , Renina/sangue
16.
J Hypertens Suppl ; 7(6): S226-7, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2561140

RESUMO

Plasma prorenin and renin changes after a bolus injection of 25 U intravenous adrenocorticotrophic hormone (ACTH, synacthen) were studied in seven untreated uncomplicated essential hypertensives over a period of 24 h. Plasma prorenin did not change significantly during the study, whereas renin after 24 h was higher than at baseline (4.3 +/- 0.6 versus 2.3 +/- 0.9 ng angiotensin I (Ang I)/ml per h, P less than 0.01). We conclude that endogenous glucocorticoid stimulation induced by exogenous ACTH and ACTH itself seem to induce a secondary or tertiary rather than a primary effect on the human renin gene.


Assuntos
Hormônio Adrenocorticotrópico/administração & dosagem , Precursores Enzimáticos/sangue , Hipertensão/sangue , Renina/sangue , Adulto , Feminino , Humanos , Hidrocortisona/sangue , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
17.
Am J Physiol ; 257(6 Pt 1): E879-84, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2692458

RESUMO

An inactive form of renin in human plasma is the biosynthetic precursor, prorenin. The cat is a good animal model for studies of inactive renin. The gene for human renin contains sequences homologous to the glucocorticoid consensus sequence. The response of cat plasma (active and inactive renin) and of angiotensinogen to administration of dexamethasone (0.5 mg/kg im, daily) was studied in ketamine-sedated cats (20 mg/kg im). Inactive renin increased by twofold after 7 days of dexamethasone (P less than 0.01). After a 7-day recovery period, it returned to base line. Active renin did not change. Angiotensinogen fell by 35% (P less than 0.01). The time course of the selective increase of plasma inactive renin showed that inactive renin began to rise after 2 days, peaking after 5 days. Ketamine alone induced inactive renin to rise slightly but significantly (P less than 0.05), although the magnitude of the increment was much less than that observed in ketamine-sedated cats receiving dexamethasone (P less than 0.01). Active renin did not change, whereas angiotensinogen was reduced by 25% (P less than 0.01). Our findings support the hypothesis that glucocorticoids might have a selective role in the synthesis and/or secretion of the precursor of renin, at least in the cat.


Assuntos
Dexametasona/farmacologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Renina/sangue , Angiotensinogênio/sangue , Animais , Gatos , Ativação Enzimática , Ketamina/farmacologia , Cinética , Valores de Referência
18.
Am J Hypertens ; 2(12 Pt 1): 920-3, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2692632

RESUMO

Activation of semipurified human kidney prorenin was found to occur in vitro in presence of a mixture of lipids that mimics the composition of the inner human cell membrane. The lipid-dependent activation was indeed only partial (38 +/- 4%) when compared to that obtained by trypsin in liquid phase (100 micrograms/mL) used as a control of maximal activation (100%) under our experimental conditions (semipurified human kidney prorenin in presence of semipurified human plasma renin substrate at a concentration of 1400 ng/mL, at pH 7.2). The phenomenon was time-dependent up to 60 min whereas the angiotensin I generated after 120 min was virtually the same as that generated after 60 min thus indicating a possible reversible activation of human prorenin. We speculate that prorenin may be reversibly activated by contact with the lipidic portion of the cell membrane either inside or outside the cells thus allowing a limited angiotensin II-generating cascade at a local site initiated by prorenin independently from the presence of active renin.


Assuntos
Membrana Celular/metabolismo , Precursores Enzimáticos/metabolismo , Lipídeos/fisiologia , Renina/metabolismo , Angiotensina I/metabolismo , Ativação Enzimática , Humanos , Metabolismo dos Lipídeos , Fatores de Tempo
19.
Boll Soc Ital Biol Sper ; 65(11): 1009-16, 1989 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-2560922

RESUMO

Red cell membrane Na(+)-K+ transport systems, renin-angiotensin-aldosterone system (RAAS) and atrial natriuretic factor (ANF) were studied in a group of 50 mild essential hypertensive patients (n = 25 for each group) age, sex and blood pressure matched. Na(+)-K+ ATPase and intracellular Na+ (Na+ i) were significantly different between the two groups (p less than 0.01). A slight difference was also seen for the Na(+)-K+ cotransport (p less than 0.05) as a likely consequence of the differences in the methodology of Na+ charge to study its efflux from the red cells in vitro. A negative correlation (r = -0.47, p less than 0.01) was observed between ANF and Na(+)-K+ cotransport suggesting an interrelationship of the two systems in the homeostasis in body fluid and electrolytes.


Assuntos
Fator Natriurético Atrial/fisiologia , Membrana Eritrocítica/metabolismo , Hipertensão/metabolismo , Potássio/farmacocinética , Sistema Renina-Angiotensina/fisiologia , Sódio/farmacocinética , Adulto , Membrana Eritrocítica/enzimologia , Feminino , Humanos , Hipertensão/sangue , Hipertensão/enzimologia , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , ATPase Trocadora de Sódio-Potássio/metabolismo
20.
Boll Soc Ital Biol Sper ; 65(11): 1017-23, 1989 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-2698184

RESUMO

Semipurified human kidney prorenin was exposed in vitro to a mixture of lipids mimicking the composition of the inner leaflet of the cell membrane, in the presence of semipurified human angiotensinogen at a concentration of 1/4 Km. Prorenin was activated in a time-dependent manner over a period of 60 min. This lipid-dependent activation was completely reversed thereafter. Pre-incubation with anti-renin serum completely prevented this activated prorenin-dependent generation of angiotensin I. Our data suggest that human prorenin can be reversibly activated by contact with the cell membrane.


Assuntos
Angiotensina I/biossíntese , Membrana Celular/metabolismo , Precursores Enzimáticos/metabolismo , Metabolismo dos Lipídeos , Renina/metabolismo , Humanos , Técnicas In Vitro
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