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1.
J Laryngol Otol ; 135(8): 723-728, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34184623

RESUMO

OBJECTIVE: To analyse the correlations between olfactory psychophysical scores and the serum levels of D-dimer, C-reactive protein, ferritin, lactate dehydrogenase, procalcitonin and neutrophil-to-lymphocyte ratio in coronavirus disease 2019 patients. METHODS: Patients underwent psychophysical olfactory assessment with the Connecticut Chemosensory Clinical Research Center test, and determination of blood serum levels of the inflammatory markers D-dimer, C-reactive protein, ferritin, lactate dehydrogenase, procalcitonin and neutrophil-to-lymphocyte ratio within 10 days of the clinical onset of coronavirus disease 2019 and 60 days after. RESULTS: Seventy-seven patients were included in this study. D-dimer, procalcitonin, ferritin and neutrophil-to-lymphocyte ratio correlated significantly with severe coronavirus disease 2019. No significant correlations were found between baseline and 60-day Connecticut Chemosensory Clinical Research Center test scores and the inflammatory markers assessed. CONCLUSION: Olfactory disturbances appear to have little prognostic value in predicting the severity of coronavirus disease 2019 compared to D-dimer, ferritin, procalcitonin and neutrophil-to-lymphocyte ratio. The lack of correlation between the severity and duration of olfactory disturbances and serum levels of inflammatory markers seems to further suggest that the pathogenetic mechanisms underlying the loss of smell in coronavirus disease 2019 patients are related to local rather than systemic inflammatory factors.


Assuntos
COVID-19/patologia , Transtornos do Olfato/etiologia , Idoso , Biomarcadores/sangue , Proteína C-Reativa/análise , COVID-19/sangue , COVID-19/complicações , Feminino , Ferritinas/sangue , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Inflamação/sangue , L-Lactato Desidrogenase/sangue , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Transtornos do Olfato/sangue , Transtornos do Olfato/patologia , Pró-Calcitonina/sangue , Índice de Gravidade de Doença
2.
ESMO Open ; 6(2): 100099, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33819752

RESUMO

BACKGROUND: The current standard first-line treatment of human epidermal growth factor receptor 2 (HER2)-positive (+) metastatic breast cancer is the combination of pertuzumab, trastuzumab and a taxane (P + T + taxane), while standard second-line is ado-trastuzumab-emtansine (T-DM1). The registration trial of pertuzumab, however, did not include early-relapsing patients, defined as patients experiencing tumor relapse ≤12 months from the end of (neo)adjuvant anti-HER2 therapy. Conversely, the pivotal trial of T-DM1 included some patients relapsing ≤6 months after the end of (neo)adjuvant trastuzumab. Thus, a proportion of early-relapsing patients are currently eligible to receive T-DM1 as first-line treatment. Nevertheless, no direct comparison exists between the two regimens in this clinical setting. PATIENTS AND METHODS: We retrospectively compared T-DM1 versus P + T + taxane as first-line treatment in two cohorts of early-relapsing patients in an Italian 'real-world' setting, involving 14 public health care institutions. The primary endpoint was progression-free survival. Secondary endpoints included patients' characterization, overall survival and post-progression survival. Univariate and multivariate analyses were carried out. All tests were two-sided and a P ≤ 0.05 was considered statistically significant. RESULTS: Among 1252 screened patients, 75 met the inclusion criteria. Forty-four (58.7%) received P + T + taxane and 31 (41.3%) received T-DM1. The two cohorts showed similar characteristics of aggressiveness and no significant differences in treatment history. T-DM1, compared with P + T + taxane was associated with worse progression-free survival (adjusted hazard ratio: 2.26, 95% confidence interval: 1.13-4.52, P = 0.021) and overall survival (adjusted hazard ratio: 3.95, 95% confidence interval: 1.38-11.32, P = 0.010), irrespective of previous (neo)adjuvant treatment, age, hormone receptors status, time-to-relapse (≤6 months or within 6-12 months) and presence of visceral/brain metastases. No differences were observed in post-progression survival (P = 0.095). CONCLUSIONS: Our study suggests superiority for P + T + taxane over T-DM1 as up-front treatment of early-relapsing HER2+ metastatic breast cancer, which merits further assessment in larger and prospective trials.


Assuntos
Neoplasias da Mama , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Itália , Recidiva Local de Neoplasia/tratamento farmacológico , Estudos Prospectivos , Receptor ErbB-2/genética , Receptor ErbB-2/uso terapêutico , Estudos Retrospectivos , Taxoides/uso terapêutico , Trastuzumab/uso terapêutico
3.
Ann Oncol ; 25(5): 1044-52, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24585722

RESUMO

BACKGROUND: The randomized, phase III AVAPERL trial evaluated the safety and efficacy of bevacizumab maintenance with or without pemetrexed in nonsquamous nonsmall-cell lung cancer (nsNSCLC). Progression-free survival (PFS) was significantly prolonged with bevacizumab-pemetrexed, but overall survival (OS) data were immature. In this article, we report an independent, updated analysis of survival outcomes in AVAPERL. PATIENTS AND METHODS: Patients with advanced nsNSCLC received first-line bevacizumab (7.5 mg/kg), cisplatin (75 mg/m(2)), and pemetrexed (500 mg/m(2)) every 3 weeks (q3w) for four cycles. Nonprogressing patients were randomized to maintenance bevacizumab (7.5 mg/kg) or bevacizumab-pemetrexed (500 mg/m(2)) q3w until progression or consent withdrawal. The primary end point of the trial was PFS; in this independent OS analysis, participating study centers were contacted to collect survival data on patients still alive at the time of the first analysis. RESULTS: A total of 376 patients received induction treatment. Disease control was confirmed in 71.9% of patients; 253 patients were randomized to maintenance treatment with bevacizumab (n = 125) or bevacizumab-pemetrexed (n = 128). At a median follow-up of 14.8 months, patients allocated to bevacizumab-pemetrexed had significantly improved PFS versus those on bevacizumab when measured from randomization [7.4 versus 3.7 months, hazard ratio (HR), 0.57, 95% confidence interval (CI) 0.44-0.75); P < 0.0001]. OS events occurred in 58% of all patients. OS was numerically longer with bevacizumab-pemetrexed versus bevacizumab when measured from randomization [17.1 versus 13.2 months, HR 0.87 (0.63-1.21); P = 0.29]. Second-line therapy was administered in 77% and 70% of patients in the bevacizumab and bevacizumab-pemetrexed arms, respectively. No new adverse events were reported during this updated analysis. CONCLUSION: In an unselected population of nsNSCLC patients achieving disease control on platinum-based induction therapy, maintenance with bevacizumab-pemetrexed was associated with a nonsignificant increase in OS over bevacizumab alone.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adenocarcinoma/mortalidade , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Feminino , Glutamatos/administração & dosagem , Guanina/administração & dosagem , Guanina/análogos & derivados , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Quimioterapia de Manutenção , Masculino , Pessoa de Meia-Idade , Pemetrexede , Modelos de Riscos Proporcionais , Qualidade de Vida , Resultado do Tratamento
4.
Int J Cancer ; 87(5): 724-7, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10925367

RESUMO

The purpose of this study was to evaluate the activity and the toxicity of the combination of gemcitabine with ifosfamide and cisplatin (GIP) in chemonaive patients with advanced non small cell lung cancer (NSCLC). Eighty chemonaive patients with Stage IIIB-IV NSCLC were treated with the combination of gemcitabine 1 g/m(2) on Days 1 and 8, ifosfamide 2 g/m(2) on Day 1 and cisplatin 80 mg/m(2) on Day 2. Cycles were administered on an outpatient basis every 3 weeks. Hematologic toxicity was the main side effect; Grade III-IV thrombocytopenia was observed in 54 (67%) patients and Grade III-IV leucopenia in 44 (55%) patients, with 4 episodes of febrile neutropenia and 1 toxic death. Thirteen patients received platelet transfusions and 38 were transfused with packed red cells. All patients were evaluable for response. The overall response rate was 54% (95% confidence interval 43 to 65%) with 1 complete response. In patients with Stage IIIB and IV disease, response rates were 58% and 52%, respectively. Median time to progression was 40 weeks (range 0-114) and median overall survival was 12 months (16.6 months for stage IIIB and 10.4 months for stage IV). Median and minimum follow-up were 19 and 12 months, respectively. The GIP combination shows a response rate and overall survival of clinical interest. Hematologic toxicity was the main toxic effect, especially in patients with low performance status. This regimen will be tested in a Phase III randomized trial.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Feminino , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neutropenia/induzido quimicamente , Trombocitopenia/induzido quimicamente
5.
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
6.
Clin Invest Med ; 14(6): 600-6, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1665404

RESUMO

We attempt to elucidate the putative indirect mechanisms by which endothelin-1 affects mean blood pressure and renal blood flow in normotensive awake rats. Endothelin-1 (700 pg/kg, i.v.) induced a short-lasting decrease followed by a prolonged increase in mean blood pressure (from 113 +/- 4 to 92 +/- 4 mmHg at 30 sec, 132 +/- 7 mmHg at 10 min, and 129 +/- 6 mmHg at 30 min, p less than 0.01), and caused a profound and long-lasting fall in renal blood flow as measured by Doppler flowmeter technique (from 2.87 +/- 0.29 to 1.40 +/- 0.37 kHz at 30 sec, 1.77 +/- 0.32 kHz at 10 min and 2.10 +/- 0.45 kHz at 30 min, p less than 0.01). Neither the receptor antagonist of bradykinin D-Arg0-Hyp3-Thi5,8-DPhe7-bradykinin (30 micrograms/kg/min, i.v.) nor the antagonist of angiotensin II Sar1, Thr8-angiotensin II (4 micrograms/kg/min, i.v.) altered the changes in mean blood pressure and renal blood flow induced by endothelin-1. The antagonist of EDRF synthesis, NG-monomethyl-L-arginine (100 micrograms/kg/min, i.v.) enhanced the endothelin-1-induced increase in mean blood pressure (endothelin-1: 20 +/- 2 mmHg vs endothelin-1 + EDRF antagonist: 39 +/- 3 mmHg at 10 min, p less than 0.01) and decrease in renal blodo flow (endothelin-1: -40 +/- 4% vs endothelin-1 + EDRF antagonist: -73 +/- 3% at 10 min, p less than 0.01).2+ mediated by the blockade of angiotensin II formation.


Assuntos
Enalaprilato/farmacologia , Endotelinas/farmacologia , Rim/irrigação sanguínea , Óxido Nítrico/antagonistas & inibidores , Vasoconstrição/efeitos dos fármacos , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos , Circulação Renal/efeitos dos fármacos , ômega-N-Metilarginina
7.
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
8.
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
9.
Am J Physiol ; 259(2 Pt 2): F304-11, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2201205

RESUMO

We investigated whether systemic and renal vasoconstriction induced by porcine endothelin (endothelin 1) is prevented by nifedipine in awake normotensive rats. Endothelin (0.07-1.4 nmol/kg iv) induced a long-lasting increase in mean blood pressure (MBP) and a decrease in renal blood flow (RBF). Maximal decrease in RBF was 25 +/- 7% (0.07 nmol/kg), 40 +/- 2 (0.35), 67 +/- 5 (0.70), and 74 +/- 8 (1.4). Hemodynamic parameters were back to base line within 35 +/- 5 min (0.07 nmol/kg), 43 +/- 6 (0.35), 60 +/- 4 (0.70), and 81 +/- 7 (1.4). Intravenous bolus injection of either angiotensin II (ANG II, 0.006-0.024 nmol/kg) or norepinephrine (0.40-1.60 nmol/kg) caused a dose-related short-lasting increase in MBP and a decrease in RBF. Endothelin was less potent than ANG II (1:3.42) and more potent than norepinephrine (1:0.015) as a renal vasoconstrictor. Nifedipine (1 mg/kg ip) was equally effective in preventing the increase in MBP caused by endothelin, norepinephrine, or ANG II. It exerted a weaker protection on the renal hemodynamic response to endothelin compared with the inhibition of the other two vasoconstrictors. Thus the regression line representing the relationship between endothelin-induced changes in MBP and RBF was steeper in rats given nifedipine (slope: vehicle, -1.33; nifedipine, -5.50; P less than 0.05). These studies suggest that nifedipine can partially prevent systemic and renal vasoconstriction caused by exogenously administered endothelin in awake normotensive rats.


Assuntos
Nifedipino/farmacologia , Peptídeos/farmacologia , Circulação Renal/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Angiotensina II/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Endotelinas , Endotélio Vascular/metabolismo , Hipertensão/prevenção & controle , Hipotensão/prevenção & controle , Masculino , Norepinefrina/farmacologia , Ratos , Ratos Endogâmicos , Análise de Regressão
10.
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
11.
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
12.
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
13.
Clin Sci (Lond) ; 78(2): 165-8, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2155743

RESUMO

1. To evaluate whether sodium intake can modulate the action of endogenous kinins on renal function and haemodynamics, a receptor antagonist of bradykinin was infused in conscious normotensive rats maintained on either a normal or a low sodium diet. 2. The antagonist inhibited the hypotensive effect of exogenously administered bradykinin. It did not change the vasodepressor effect of acetylcholine, dopamine or prostaglandin E2. 3. The antagonist did not affect mean blood pressure, glomerular filtration rate, renal blood flow or urinary sodium excretion, in rats on sodium restriction. It did not change mean blood pressure, glomerular filtration rate or urinary sodium excretion, but decreased renal blood flow, in rats on a normal sodium intake. 4. The kallikrein-kinin system has a role in the regulation of renal blood flow in rats on a normal sodium diet.


Assuntos
Bradicinina/análogos & derivados , Bradicinina/antagonistas & inibidores , Hemodinâmica/efeitos dos fármacos , Rim/fisiologia , Sódio/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Bradicinina/farmacologia , Dieta , Rim/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos , Circulação Renal/efeitos dos fármacos , Sódio/administração & dosagem
14.
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
15.
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
16.
J Cardiovasc Pharmacol ; 14(6): 818-25, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2481767

RESUMO

The effects of endothelin on regional hemodynamics and renal function were studied in awake normotensive rats. Intravenous injection of endothelin (700 pmol/kg) transiently lowered mean blood pressure (from 108 +/- 2 to 84 +/- 2 mm Hg, p less than 0.01), due to a reduction in total vascular resistance (38 +/- 1%, p less than 0.01), and increased stroke volume (29 +/- 5%, p less than 0.01) and heart rate (from 399 +/- 18 to 447 +/- 18 bpm, p less than 0.05); mesenteric and renal blood flow was reduced (37 +/- 13, p less than 0.05 and 63 +/- 5%, p less than 0.01), whereas carotid blood flow was increased (78 +/- 5%, p less than 0.01). This effect was followed by long-lasting hypertension due to increased total vascular resistance (112 +/- 19%, p less than 0.01); stroke volume, mesenteric, and renal blood flow were reduced (34 +/- 5, 41 +/- 4, and 58 +/- 4%, respectively, p less than 0.05) and carotid blood flow returned to basal levels. Bilateral nephrectomy enhanced the initial hypotensive effect. Pretreatment with nifedipine blocked the hypertensive effect, whereas bilateral nephrectomy did not. A subpressor dose of endothelin (70 pmol/kg) had no effect on stroke volume, mesenteric blood flow, glomerular filtration rate, and plasma renin activity; carotid blood flow was transiently increased (48 +/- 16%, p less than 0.05), then returned to basal levels; renal blood flow decreased (22 +/- 6 and 15 +/- 4% at 30 s and 10 min, respectively p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Rim/efeitos dos fármacos , Peptídeos/farmacologia , Angiotensina II/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Endotelinas , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Rim/irrigação sanguínea , Testes de Função Renal , Nefrectomia , Norepinefrina/farmacologia , Peptídeos/metabolismo , Potássio/urina , Ratos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Renina/sangue , Reologia , Sódio/urina
17.
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
18.
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
19.
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
20.
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
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