RESUMO
The differences in systemic T-cell responses between patients with psoriatic arthritis (PsA) and patients with cutaneous psoriasis (Ps) are still largely unknown. To determine differential features that could be used to distinguish PsA from Ps, we compared the cytokine secretion profile of circulating T cells in patients with PsA, patients with cutaneous Ps and control subjects. We determined Th1, Th2 and Th17 cytokine secretion of anti-CD3-stimulated peripheral blood mononuclear cells (PBMCs) using a cytokine bead array. Normality of data distribution was assessed by the Shapiro-Wilk test, and statistical significance was calculated by the Mann-Whitney test. Phenotypic characterization of circulating T cells was performed by fluorescence-activated cell sorting analysis. We found that the major systemic differences distinguishing PsA from cutaneous Ps were the increased secretion of interleukin (IL)-2 by α-CD3-stimulated PBMCs and a higher percentage of circulating CD3+ T cells expressing the proliferation marker CD71 in PsA. These results indicate IL-2 as a possible biomarker of PsA, and suggest a role of circulating T cells with high proliferative capacity in the pathogenesis of PsA.
Assuntos
Artrite Psoriásica/metabolismo , Complexo CD3/imunologia , Interleucina-2/metabolismo , Leucócitos Mononucleares/metabolismo , Psoríase/metabolismo , Adolescente , Adulto , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Auxiliares-Indutores/metabolismo , Adulto JovemRESUMO
Amicrobial pustulosis associated with autoimmune diseases (APAD) is a clinical entity which was described only recently and few cases are reported in the literature. This condition is characterized by recurrent acute onset with pustular lesions predominantly involving skin folds, genitals, scalp and external auditory canals of young women. The etiopathogenesis of APAD is unknown and the most effective therapeutic treatment seems to be systemic corticosteroids. We describe the case of a 16-year old female patient suffering from APAD successfully treated with cyclosporine A.
Assuntos
Doenças Autoimunes/tratamento farmacológico , Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Dermatopatias Vesiculobolhosas/tratamento farmacológico , Adolescente , Feminino , HumanosRESUMO
Psoriasis is an immune-mediated disease with a chronic relapsing course, and the particularly severe forms that are refractory to traditional therapies are often difficult to manage. Everolimus (Certican; Novartis, Basel, Switzerland) is a new rapamycin-derived macrolide that is used in the prophylaxis of rejection in heart and kidney transplant patients. The mechanism underlying its immunosuppressant and antiproliferative activity is different from, but complementary to, that of calcineurin inhibitors such as ciclosporin. We describe a woman with severe psoriasis treated with everolimus combined with subtherapeutic doses of ciclosporin.
Assuntos
Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Psoríase/tratamento farmacológico , Sirolimo/análogos & derivados , Sinergismo Farmacológico , Quimioterapia Combinada , Everolimo , Feminino , Humanos , Pessoa de Meia-Idade , Sirolimo/uso terapêutico , Resultado do TratamentoRESUMO
Granuloma annulare is an anatomo-clinical entity that is frequently encountered in everyday dermatological practice. We report our experience regarding 4 patients with disseminated granuloma annulare. Each patient was treated with a cycle of cyclosporine therapy for six weeks. A cycle of systemic cyclosporine therapy was started at a dose of 4 mg/kg/day for four weeks, subsequently reduced by 0.5 mg/kg/day every two weeks. The clinical picture more or less completely resolved within three weeks in all of the patients, and there were no relapses during the dose-tapering period or the following 12 months. Cyclosporine was optimally tolerated by all four patients, none of whom experienced any therapy-related side effects. Cyclosporine is a valid therapeutic option for the treatment of disseminated granuloma annulare, although we recommend its use in a protected hospital environment that facilitates patient monitoring.
Assuntos
Ciclosporina/uso terapêutico , Granuloma Anular/tratamento farmacológico , Imunossupressores/uso terapêutico , Feminino , Granuloma Anular/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Pele/patologiaRESUMO
Psoriasis is a T-lymphocyte mediated autoimmune disease. The response to therapies targeting T-lymphocytes suggest that the latter is a key cell in the pathogenesis of the disease. Cyclosporine (CsA) inhibits the proliferation and the IL-2 dependent expansion of T-lymphocytes. Ultraviolet radiation is an effective treatment for psoriasis. Several studies have demonstrated a significant improvement of the therapeutic response when narrow-band radiation is issued by TL-01 fluorescent lamp compared to broad- band UVB issued by other fluorescent sources. The effects of UVB on the immune system appear to be limited to the cell-mediated compartment of the immune response. In order to reduce the cumulative dose of UVB and limit the toxicity of drugs in the therapy of psoriasis, phototherapy with UVB has been used as treatment in association with other standard therapies. The purpose of the study is to evaluate, in patients with moderate to severe psoriasis a combined therapy with Cyclosporine A and 311 nm UVB phototherapy.
Assuntos
Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Psoríase/terapia , Terapia Ultravioleta , Adulto , Terapia Combinada , Ciclosporina/efeitos adversos , Feminino , Humanos , Imunossupressores/efeitos adversos , Masculino , Pessoa de Meia-Idade , Psoríase/tratamento farmacológico , Psoríase/radioterapia , Pele/patologia , Terapia Ultravioleta/efeitos adversosRESUMO
The short-term effects of extracellular fluid volume depletion on the generation of some bioregulators of the renal function have been studied in healthy women. Eight subjects (SD group) were submitted to a low NaCl dietary intake and natriuretic treatment. At the end of the treatment (6 days) a cumulative sodium deficit of 381 +/- 55 mmol (mean +/- SEM) and a body weight variation of -2.1 +/- 0.28 kg were estimated. The renal function was explored by clearance method during hypotonic polyuria induced by oral water load and subsequent antidiuresis induced by low-dose infusion of lysine-8-vasopressin. The basal values of plasma renin activity were determined just before the water load as well as the urinary aldosterone excretion of the foregoing 24 hours was. During the renal functional exploration the urinary concentrations of PGE2, 6-keto-PGF1 alpha (6KPGF) and TxB2 were determined by RIA method. We report also, as comparison terms, the results obtained either in potassium depletion (KD group, n = 12) or in normal sodium and potassium balance (N group, n = 20). 1) In the SD vs N group-besides the increase in renin and aldosterone secretion-the behaviour of urinary prostanoids is consistent with a stimulation of the renal synthesis of PGI2 and TxA2 as well as of PGE2, at least as a trend. 2) In the KD vs N group an increase in renin secretion occurred while the urinary aldosterone was not significantly decreased. The urinary prostanoid data suggest an inhibition of the renal synthesis of PGE2 and PGI2. All three urinary prostanoids were significantly lower in the KD as compared to the SD group. Thus, in salt depletion the renal prostanoid synthesis was enhanced while it was depressed in potassium depletion, despite the increased renin secretion.
Assuntos
Homeostase , Hipopotassemia/metabolismo , Hiponatremia/metabolismo , Rim/metabolismo , Potássio/metabolismo , Prostaglandinas/biossíntese , Sódio/metabolismo , Adulto , Aldosterona/sangue , Amilorida/farmacologia , Peso Corporal/efeitos dos fármacos , Clortalidona/farmacologia , Dieta Hipossódica , Diuréticos/farmacologia , Feminino , Humanos , Hidroclorotiazida/farmacologia , Hipopotassemia/induzido quimicamente , Hiponatremia/induzido quimicamente , Testes de Função Renal , Poliúria/induzido quimicamente , Poliúria/metabolismo , Prostaglandinas/urina , Valores de Referência , Renina/sangue , Sistema Renina-Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/fisiologia , ÁguaRESUMO
The acute effects of angiotensin converting enzyme inhibition on the renal function and urinary prostanoids were studied. Healthy women were studied in both sodium depletion (n = 8) and normal balance of sodium and potassium (n = 6). Each woman underwent paired renal functional explorations (by the clearance method during hypotonic polyuria and subsequent antidiuresis) in the absence and in the presence of enalapril. In both experimental conditions enalapril failed to affect urinary prostanoid excretions. Only in the presence of hyperreninemia induced by salt depletion, enalapril was effective in inducing renal tubular effects only partly consistent with a depressed activity of angiotensin-aldosterone system. Specifically, in sodium depletion enalapril treatment promoted a decreasing trend in urinary salt excretion, dependent in turn on selective stimulation of the distal tubule NaCl transport. Furthermore, plasma potassium concentration was reduced despite the concomitant decrease in urinary potassium excretion.
Assuntos
Angiotensina II/fisiologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Enalapril/farmacologia , Hiponatremia/metabolismo , Rim/efeitos dos fármacos , Prostaglandinas/biossíntese , Adulto , Amilorida/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Dieta Hipossódica , Diurese/efeitos dos fármacos , Diuréticos/farmacologia , Feminino , Humanos , Hidroclorotiazida/farmacologia , Hiponatremia/induzido quimicamente , Rim/metabolismo , Testes de Função Renal , Poliúria/induzido quimicamente , Poliúria/metabolismo , Potássio/metabolismo , Prostaglandinas/urina , Valores de Referência , Sistema Renina-Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/fisiologia , Sódio/metabolismoRESUMO
Plasma renin activity (PRA) and urinary aldosterone excretion were determined in healthy women with normal potassium balance (N, n = 20) or experimental potassium depletion (KD). KD was induced by natriuretic treatment--associated with replacement of net NaCl and water losses--and low dietary potassium intake (< or = 10 mmol/d). By using different depletion patterns, three groups were obtained with cumulative potassium deficits (mean +/- SEM) of 160 +/- 43 (KD1, n = 8), 198 +/- 22 (KD2, n = 6) and 215 +/- 54 mmol (KD3, n = 6). The renal function by the clearance (cl.) method and urinary concentrations of prostaglandin E2 (PGE2), 6-keto-PGF1 alpha (6KPGF), and thromboxane B2 (TXB2) by the RIA method were estimated during hypotonic polyuria (oral water load) and subsequent moderate antidiuresis induced by low-dose infusion of lysine-8-vasopressin (LVP). 1. In all KD groups the depletion treatment significantly reduced both potassium plasma concentration (PK) and urinary potassium excretion while it increased basal PRA; the basal urinary aldosterone excretion was not significantly different from normokalemic controls. In the KD3 vs KD1 group the P kappa value was significantly lower. 2. In both KD2 and KD3 groups as compared to the N group, several hypokalemic-like renal dysfunctions--absent in the KD1 group--occurred. Particularly, in the KD2 + KD3 vs N group the renal ability in both urine diluting (water load) and concentrating (LVP infusion) was significantly impaired.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Hipopotassemia/fisiopatologia , Rim/fisiopatologia , Prostaglandinas/fisiologia , Sistema Renina-Angiotensina/fisiologia , 6-Cetoprostaglandina F1 alfa/urina , Adulto , Aldosterona/urina , Pressão Sanguínea , Dinoprostona/urina , Diurese , Feminino , Taxa de Filtração Glomerular , Humanos , Pessoa de Meia-Idade , Natriurese , Poliúria/urina , Potássio/urina , Potássio na Dieta/administração & dosagem , Renina/sangue , Tromboxano B2/urinaRESUMO
We studied 179 psoriatic patients by semistructured colloquia and psychometric tests and determined their cutaneous psycho-neurophysiological profiles by biofeedback methods. The Paykel scale for stressful events showed that 72% of psoriatics had experienced significant stressful events about one month before the appearance of the psoriasis. The Zung test for anxiety and depression showed a high level of anxiety in the psoriatic patients. 64% of the patients who were treated by BFBtraining had a decrease in their PASI index for severity and the extent of the disease and also fewer recurrences at the one-year follow-up. The results of the World Experience Inventory indicated difficulties related to body image and to relationships with others. Psoriasis influenced the sexuality of the patients. It is always difficult when one is afflicted by ill health to enjoy life and the general scores of SWL (Satisfaction with Life), were significantly lower than those of a control group.
Assuntos
Psoríase/psicologia , Adulto , Idoso , Ansiedade/complicações , Depressão/diagnóstico , Humanos , Pessoa de Meia-Idade , Psoríase/patologia , Testes Psicológicos , Qualidade de Vida , Estresse Psicológico/complicaçõesRESUMO
By using two similar dietary and pharmacological patterns of potassium depletive treatment, two experimental groups--KD2 (n = 6) and KD3 (n = 6)--with cumulative potassium deficit not significantly different, were obtained. The basal values of plasma potassium concentration and PRA, as well as the expression of renal hypokalemic dysfunction were not significantly different. Paired studies in the absence and presence of indomethacin (KD2 group) or enalapril (KD3 group) were performed. The aim of the research was evaluation of the effective roles of prostanoid and angiotensin (AT) II systems in renal hypokalemic dysfunction. The results show that: 1) AT II and cortical vasodilating prostanoids exerted opposite effects on the preglomerular arteriolar tone; 2) medullary prostanoids antagonized the vasopressin effects. Therefore, in potassium depletion the decreased synthesis of cortical and medullary prostanoids, in the face of the increased generation of AT II, contributed to reducing the glomerular filtration rate and facilitate the expression of vasopressin action. These components of the renal hypokalemic dysfunction probably exert a protective role with regard to the urinary chloride and potassium losses.
Assuntos
Angiotensina II/fisiologia , Hipopotassemia/fisiopatologia , Rim/fisiopatologia , Potássio/metabolismo , Prostaglandinas/fisiologia , Cloretos/metabolismo , Creatinina/sangue , Diurese/efeitos dos fármacos , Enalapril/farmacologia , Feminino , Humanos , Indometacina/farmacologia , Rim/efeitos dos fármacos , Natriurese/efeitos dos fármacos , Potássio na Dieta/administração & dosagem , Prostaglandinas/biossíntese , Água/administração & dosagemRESUMO
In order to investigate the renal functional effects of potassium depletion (KD) we have submitted 20 healthy women to different potassium depletive treatments by dietary and pharmacological means. By changing these treatments we have obtained three KD groups with cumulative potassium deficit of 160 +/- 43 (KD1, n = 8), 198 +/- 22 (KD2, n = 6) and 214 +/- 54 mmol (KD3, n = 6). Another 20 subjects were also studied as controls in normal potassium balance (N group). In all subjects the renal function has been evaluated by clearance (cl.) technique both during induced hypotonic polyuria and subsequent moderate antidiuresis induced by low dose infusion of lysine-8-vasopressin (LVP). A renal dysfunction occurred in differences between these two groups, they have been pooled in a single KD2 + KD3 group. In this group as compared to N the following renal dysfunctions were observed during hypotonic polyuria: a) reduction in creatinine cl. (in absence of significant differences in mean arterial pressure); b) inhibition of the fractional reabsorption of chloride by diluting segments; c) depression of the diuretic response to water load. Moreover in KD the LVP was less effective in reducing the creatinine cl. while it became effective in reducing the fractional excretions of NaCl. These findings indicate that the degree of KD reached in the KD2 + KD3 group was adequate to induce a renal dysfunction similar to that occurring in conditions of chronic hypokalemia. It is probable that hypokalemia by itself along with changes of both prostaglandin and angiotensin renal systems are involved in this renal dysfunction.
Assuntos
Hipopotassemia/fisiopatologia , Rim/fisiopatologia , Deficiência de Potássio/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Cloretos/metabolismo , Creatinina/metabolismo , Diurese/efeitos dos fármacos , Feminino , Humanos , Lipressina/farmacologia , Taxa de Depuração Metabólica/efeitos dos fármacos , Poliúria/fisiopatologia , Potássio na Dieta/administração & dosagemRESUMO
In healthy women we have studied the effects of potassium depletions of different degrees on the generation of some bioregulators of hydro-saline balance. The study has been performed on 20 women in normal potassium balance (N group) and 20 women submitted to potassium depletive treatment by dietary and pharmacological means. On the basis of different patterns of treatment we have obtained three groups i.e. KD1 (n = 8), KD2 (n = 6) and KD3 (n = 6) with potassium cumulative deficit of 160 +/- 43, 198 +/- 22 and 214 +/- 54 mmol, respectively. The renal function was assessed by the clearance method during induced hypotonic polyuria and subsequent moderate antidiuresis induced by low dose infusion of lysine-8-vasopressin. The urinary PGE2, 6-keto-PGF1 (6KPGF) and TxB2 were determined by the RIA method. Moreover, the basal PRA and urinary aldosterone were determined before the renal functional exploration. The data obtained in both KD2 and KD3 groups where renal hypokalemic dysfunctions occurred--indicate that hypokalemia stimulated renin secretion and inhibited the reactivity of renal prostanoid production to the polyuric stimulus. However, in the KD3 group--where the circulating levels of renin, and probably of angiotensin II were the highest--the hypokalemic depression of the synthesis of 6KPGF and TxB2 precursors was attenuated while the synthesis of PGE2 was still inhibited.
Assuntos
Aldosterona/urina , Rim/fisiopatologia , Deficiência de Potássio/fisiopatologia , Renina/sangue , Desequilíbrio Hidroeletrolítico/fisiopatologia , Adulto , Ácido Araquidônico/metabolismo , Diurese/efeitos dos fármacos , Feminino , Humanos , Hipopotassemia/fisiopatologia , Lipressina/farmacologia , Poliúria/fisiopatologia , Potássio na Dieta/administração & dosagem , Prostaglandinas/biossínteseRESUMO
The urinary concentrations of prostaglandins(PG) E2, 6-keto-PGF1 alpha (6KPGF) and thromboxane (Tx) B2 were measured by RIA method during both hypotonic polyuria (oral water load) and subsequent antidiuresis (low-dose infusion of lysine-8-vasopressin). The study was performed on healthy women either in normal potassium balance (N, n = 14) or sustained potassium depletion (D3, n = 6). Potassium depletion (KD) was induced by low potassium dietary intake (less than or equal to 10 mmol/d) and natriuretic treatment over a period of 8 days; the net losses of NaCl and H2O were replaced; the cumulative potassium deficit was 198 +/- 22 mmol. Further studies were performed after indomethacin treatment in both experimental conditions. 1) As compared to normal potassium balance in KD group the urinary prostanoid excretions were reduced even in absence of significant differences in urinary flow rate. The urinary excretion of 6KPGF was more impaired than that of TxB2 in both polyuria and antidiuresis. 2) Indomethacin inhibited the urinary prostanoid excretions in normal potassium balance and KD groups. The urinary excretion of PGE2 was more impaired than that of both 6KPGF and TxB2.
Assuntos
Deficiência de Potássio/urina , Prostaglandinas/urina , Adulto , Diurese , Feminino , Humanos , Indometacina/farmacologia , Natriurese , Potássio/administração & dosagemRESUMO
During hypotonic polyuria renal function studies by the clearance (cl.) method, and urinary PGE2, 6-keto-PGF1 alpha and TxB2 determinations were performed on 14 healthy women in normal potassium balance (N) and 14 healthy women in sustained potassium depletion (KD) induced by low dietary potassium intake (less than or equal to 10 mmol day-1) and natriuretic treatment. By using different depletive patterns, two groups with estimated cumulative potassium deficits of 160 +/- 43 mmol (KD1, n = 8) and 198 +/- 22 mmol (KD2, n = 6), respectively, were obtained. (1) In both the KD1 and KD2 groups as compared to normal potassium balance (N), plasma potassium concentration and urinary potassium excretion were significantly lower; plasma renin activity was significantly higher. (2) Only in KD2 did significant changes appear in renal function and urinary prostanoid excretions. Besides a decrease in creatinine cl. and the urinary flow rate, an increase in fractional chloride excretion and a reduction in distal fractional chloride reabsorption were manifest. The plasma chloride concentration was reduced too. Urinary prostanoid excretions were significantly (6-keto-PGF1 alpha, TxB2) or tendentially (PGE2) lower. (3) Indomethacin treatment resulted in changes in mean arterial pressure (increase) and creatinine cl. (decrease) which were not significantly different in normal potassium balance and KD groups. Only in KD2 did the drug significantly reduce the fractional salt and water excretions and the fractional sodium and chloride deliveries to the diluting segments. However, indomethacin was unable to correct the inhibition of distal fractional chloride reabsorption. Therefore, the potassium depletion attained in the KD2 group was efficacious in depressing renal prostanoid synthesis. This fact, in the presence of high levels of angiotensin II, induced a reduction of the glomerular filtration rate thus contributing to renal ability to retain chloride and potassium.
Assuntos
Rim/metabolismo , Poliúria/urina , Deficiência de Potássio/urina , Prostaglandinas/urina , Adulto , Análise de Variância , Feminino , Humanos , Indometacina/farmacologia , Rim/efeitos dos fármacos , Testes de Função Renal , Lipressina , Radioimunoensaio , Análise de RegressãoRESUMO
Renal function has been studied by the clearance (cl.) method during hypotonic polyuria--four 15-min cl. periods--and successive antidiuresis--two 60-min cl. periods (A1, A2)--induced by lysine-8-vasopressin (LVP), 5 mU in bolus followed by infusion at a rate of 0.04 mU/min. The endogenous creatinine cl. (Cc) and the osmotic cls. (Cosm, CH2O) were determined by the usual methods as well as the absolute and fractional urinary excretions of water, sodium, chloride and potassium. The urinary concentrations of PGE2, 6-keto-PGF1 alpha and TxB2 were determined by the RIA method. This study protocol has been applied to 28 healthy women either in normal potassium balance (N, n = 14) or after potassium depletion (KD) induced by low potassium dietary intake (less than or equal to 10 meq/d) plus natriuretic treatment according to two different time patterns: two KD groups were obtained with potassium cumulative deficit of 160 +/- 43 (D2, n = 8) and 198 +/- 22 meq (D3, n = 6). The early % effects of LVP, i.e. (A1-P)% of P (mean polyuria), were significantly different only in D3 as compared to N. Precisely, the LVP-effect to reduce Cc was blunted; moreover a LVP-effect to reduce renal sodium and chloride fractional excretions and a tendentiously enhanced LVP-effect to reduce water fractional excretion were observed. These tubular effects are likely related to the inhibited renal synthesis of prostanoids in the D3 group.
Assuntos
Rim/efeitos dos fármacos , Lipressina/farmacologia , Poliúria/fisiopatologia , Deficiência de Potássio/fisiopatologia , 6-Cetoprostaglandina F1 alfa/urina , Dinoprostona/urina , Feminino , Humanos , Rim/fisiopatologia , Deficiência de Potássio/urina , Tromboxano B2/urinaRESUMO
Renal function has been studied by the clearance (cl.) method during hypotonic polyuria--four 15-min cl. periods--and successive antidiuresis--two 60-min cl. periods (A1, A2)--induced by lysine-8-vasopressin (LVP), 5 mU in bolus followed by infusion at a rate of 0.04 mU/min. The endogenous creatinine cl. (Cc) and the osmotic cls. (Cosm, CH2O) were determined by the usual methods as well as the absolute and fractional urinary excretions of water, sodium, chloride and potassium. The urinary concentrations of PGE2, 6-keto-PGF1 alpha and TxB2 were determined by the RIA method. This study protocol has been applied to 20 healthy women submitted to paired functional explorations in both the absence and presence of indomethacin (100 mg i.m.); the drug effects have been evaluated in both normal potassium balance (N2, n = 6) and in two groups of potassium depletion (KD) with potassium cumulative deficit of 160 +/- 43 (D2, n = 8) and 198 +/- 22 meq (D3, n = 6), respectively. As regards the early % effects of LVP, i.e. (A1-P)% of P (mean polyuria), the inhibition of prostanoid synthesis with indomethacin produced significant changes: 1) an enhanced reduction in renal chloride excretion in all experimental groups; 2) a reduction in renal sodium and chloride fractional excretions in both KD groups; 3) an enhanced antidiuretic effect in D3 only, i.e. in the experimental condition with inhibition of prostanoid renal synthesis present during the control study.
Assuntos
Indometacina/farmacologia , Rim/efeitos dos fármacos , Lipressina/farmacologia , Poliúria/fisiopatologia , Deficiência de Potássio/fisiopatologia , 6-Cetoprostaglandina F1 alfa/urina , Dinoprostona/urina , Feminino , Humanos , Rim/fisiopatologia , Deficiência de Potássio/urina , Tromboxano B2/urinaRESUMO
The renal function has been evaluated by clearance (cl.) method during hypotonic polyuria and successive moderate antidiuresis induced by a low dose of lysine-8-vasopressin; four 15 min and two 60 min cl. periods were performed, respectively. Glomerular filtration rate was estimated by creatinine cl.; the osmotic cl. (Cosm, CH2O), the absolute and fractional excretions of water, sodium, potassium and chloride were determined by usual methods. The urinary concentrations of PGE2, 6-keto-PGF1 alpha (6KPGF) and TxB2 were measured by RIA. The study protocol was applied in normal potassium balance and experimental potassium balance (KD), both in absence and presence of indomethacin. In KD groups with a potassium cumulative deficit of 198.4 +/- 22.2 meq (D3; n = 6) during polyuria significant correlations are consistent with the hypothesis that the lower the plasma potassium concentration is the higher the urinary chloride excretion and the inhibition of distal fractional chloride reabsorption. Moreover, by utilizing the polyuria and antidiuresis data pool, the effects of urine flow rate changes on PGE2 and 6KPGF urinary excretions are blunted as compared to normal potassium balance (n = 14). After indomethacin treatment (D3.I) the following functional relationships are disclosed: a) the lower the kaliemia is the lower the urinary chloride and potassium excretions and the higher the fractional isosmotic reabsorption; b) the lower the urinary potassium excretion is the lower the urinary chloride excretion. In both D3 and D3.I experimental groups the positive correlation between urinary chloride excretion and urinary potassium excretion is significant.