Our aim was to understand mechanisms responsible for excessive electrolyte loss in the sweat gland and the potential impact on fluid balance during exercise in heat stress conditions. Human physiological testing under exercise/heat stress and immunofluorescence staining of sweat glands from skin biopsies were compared between healthy individuals (with normal and high sweat sodium chloride concentration, [NaCl]) and with cystic fibrosis patients (CF), who exhibit excessively salty sweat due to a defect of Cl- channel cystic fibrosis transmembrane conductance regulator (CFTR). Three novel findings are presented. First, excessively salty sweat may be associated with reduced expression of CFTR in the sweat gland reabsorptive duct of healthy individuals in addition to in those with CF; however, although a link to a CF gene mutation in healthy individuals with high sweat [NaCl] was not demonstrated, the possibility of an undetected CFTR mutation or polymorphism remains to be investigated as an underlying mechanism. Two, CF and healthy individuals with excessively salty sweat respond to moderate dehydration (3% body weight loss during exercise) with an attenuated rise in serum osmolality, greater relative loss in plasma volume, but similar perceived thirst compared to healthy individuals with "normal" sweat [NaCl]. However, individuals with CF respond to rehydration with hypotonic beverage by drinking less ad libitum in response to reduced serum [NaCl], suggesting that thirst-guided fluid replacement may be more appropriate for this population rather than restoring 100% of sweat loss following dehydration as is often recommended in healthy individuals.

A concentração de eletrólitos no suor e a taxa de sudorese estão bem descritas em atletas que treinam na terra e em não atletas. Embora exista alguma pesquisa acerca das respostas termorregulatórias de nadadores, não foi encontrada alguma que tenha verificado a concentração eletrolítica no suor. O objetivo deste estudo foi comparar a taxa de sudorese e a composição eletrolítica no suor de nadadores, corredores e não atletas. Dez nadadores (23 ± 3 anos, 179 ± 6 cm, 75 ± 7 kg), dez corredores (26 ± 3 anos, 178 ± 4 cm, 74 ± 7 kg) e dez não atletas (26 ± 3 anos, 178 ± 6 cm, 79 ± 8 kg) pedalaram em um ciclo ergômetro (CYBEX, The bike,USA) por 30 min a 32oC e 60% de umidade relativa. O esforço estabelecido foi de 10% abaixo do segundo limiar anaeróbico. O suor foi coletado por meio de adesivos absorventes (Tegaderm 3582, 3M, Neuss, Germany) colocados na escápula direita após a limpeza apropriada da pele. Após o término do exercício, os adesivos foram colocados em uma seringa e o suor colocado em um tubo. As concentrações de sódio (Na+), cloro (Cl-) e potássio (K+) no suor foram analisadas através de um seletor de ions (AVL 9180). Média e desvio padrão foram calculados através da estatística descritiva. As diferenças foram estabelecidas usando ANOVA fatorial e teste post hoc de Tukey. A taxa de sudorese foi maior no grupo dos corredores. As concentrações de Na+ e Cl- foram menores no grupo dos corredores do que nos outros grupos. A concentração de K+ não mostrou diferença entre os grupos. As concentrações eletrolíticas do suor dos corredores estão de acordo com os valores previamente publicados para atletas. No entanto, as concentrações de Na+ e Cl- no suor dos nadadores foram similares as dos não atletas, provavelmente porque a regulação da sudorese dentro da água é diferente daquela que ocorre fora dela. / Sweat electrolyte concentration and sweat rate have been reported in athletes trained on land and in nonathletes. Although there is some research on thermoregulatory responses in swimmers, none of them have addressed the sweat electrolyte concentration. The purpose of this study was to compare sweat electrolyte concentration and sweat rate among swimmers runners and non-athletes. Ten swimmers (age 23 ± 3 years, height 179 ± 6 cm, body mass 75 ± 7 kg), 10 runners (age 26 ± 3 years, height 178 ± 4 cm, body mass 74 ± 7 kg) and 10 nonathletes (age 26 ± 3 years, height 178 ± 6 cm, body mass 79 ± 8 kg) cycled on a eletromagnetic-braked ergometer (CYBEX, The bike,USA) for 30 min at 32oC and 60% relative humidity. The work rate was set at 10% below second anaerobic threshold. Sweat was collected by absorbent patches (Tegaderm 3582, 3M, Neuss, Germany) from the scapula. All patches were placed on the right hand side of the body after appropriate cleaning of the skin. After exercise was completed, patches were set into a syringe and sweat was squeezed in a tube. Sweat was analysed for sodium (Na+), cloride (Cl-) and potassium (K+) concentration by ion selector (AVL, 9180). Mean and SD are given as descriptive statistics. Differences were established using ANOVA factorial and Tukey post hoc test. Sweat rate of runners were higher than that of swimmers and nonathletes. Na+ and Cl- concentrations of sweat in the runners group were different from that of the swimmers and nonathletes. K+ concentration did not show difference among the 3 groups. Sweat electrolyte concentrations of runners were within the normal range for athletes. However, sweat Na+ and Cl- concentrations of swimmers were more similar to that of nonatlhetles, and this is probably because regulation of sweating during exercise in water is different from that during exercise on land.

A concentração de eletrólitos no suor e a taxa de sudorese estão bem descritas em atletas que treinam na terra e em não atletas. Embora exista alguma pesquisa acerca das respostas termorregulatórias de nadadores, não foi encontrada alguma que tenha verificado a concentração eletrolítica no suor. O objetivo deste estudo foi comparar a taxa de sudorese e a composição eletrolítica no suor de nadadores, corredores e não atletas. Dez nadadores (23 ± 3 anos, 179 ± 6 cm, 75 ± 7 kg), dez corredores (26 ± 3 anos, 178 ± 4 cm, 74 ± 7 kg) e dez não atletas (26 ± 3 anos, 178 ± 6 cm, 79 ± 8 kg) pedalaram em um ciclo ergômetro (CYBEX, The bike,USA) por 30 min a 32oC e 60% de umidade relativa. O esforço estabelecido foi de 10% abaixo do segundo limiar anaeróbico. O suor foi coletado por meio de adesivos absorventes (Tegaderm 3582, 3M, Neuss, Germany) colocados na escápula direita após a limpeza apropriada da pele. Após o término do exercício, os adesivos foram colocados em uma seringa e o suor colocado em um tubo. As concentrações de sódio (Na+), cloro (Cl-) e potássio (K+) no suor foram analisadas através de um seletor de ions (AVL 9180). Média e desvio padrão foram calculados através da estatística descritiva. As diferenças foram estabelecidas usando ANOVA fatorial e teste post hoc de Tukey. A taxa de sudorese foi maior no grupo dos corredores. As concentrações de Na+ e Cl- foram menores no grupo dos corredores do que nos outros grupos. A concentração de K+ não mostrou diferença entre os grupos. As concentrações eletrolíticas do suor dos corredores estão de acordo com os valores previamente publicados para atletas. No entanto, as concentrações de Na+ e Cl- no suor dos nadadores foram similares as dos não atletas, provavelmente porque a regulação da sudorese dentro da água é diferente daquela que ocorre fora dela. / Sweat electrolyte concentration and sweat rate have been reported in athletes trained on land and in nonathletes. Although there is some research on thermoregulatory responses in swimmers, none of them have addressed the sweat electrolyte concentration. The purpose of this study was to compare sweat electrolyte concentration and sweat rate among swimmers runners and non-athletes. Ten swimmers (age 23 ± 3 years, height 179 ± 6 cm, body mass 75 ± 7 kg), 10 runners (age 26 ± 3 years, height 178 ± 4 cm, body mass 74 ± 7 kg) and 10 nonathletes (age 26 ± 3 years, height 178 ± 6 cm, body mass 79 ± 8 kg) cycled on a eletromagnetic-braked ergometer (CYBEX, The bike,USA) for 30 min at 32oC and 60% relative humidity. The work rate was set at 10% below second anaerobic threshold. Sweat was collected by absorbent patches (Tegaderm 3582, 3M, Neuss, Germany) from the scapula. All patches were placed on the right hand side of the body after appropriate cleaning of the skin. After exercise was completed, patches were set into a syringe and sweat was squeezed in a tube. Sweat was analysed for sodium (Na+), cloride (Cl-) and potassium (K+) concentration by ion selector (AVL, 9180). Mean and SD are given as descriptive statistics. Differences were established using ANOVA factorial and Tukey post hoc test. Sweat rate of runners were higher than that of swimmers and nonathletes. Na+ and Cl- concentrations of sweat in the runners group were different from that of the swimmers and nonathletes. K+ concentration did not show difference among the 3 groups. Sweat electrolyte concentrations of runners were within the normal range for athletes. However, sweat Na+ and Cl- concentrations of swimmers were more similar to that of nonatlhetles, and this is probably because regulation of sweating during exercise in water is different from that during exercise on land.

A concentração de eletrólitos no suor e a taxa de sudorese estão bem descritas em atletas que treinam na terra e em não atletas. Embora exista alguma pesquisa acerca das respostas termorregulatórias de nadadores, não foi encontrada alguma que tenha verificado a concentração eletrolítica no suor. O objetivo deste estudo foi comparar a taxa de sudorese e a composição eletrolítica no suor de nadadores, corredores e não atletas. Dez nadadores (23 ± 3 anos, 179 ± 6 cm, 75 ± 7 kg), dez corredores (26 ± 3 anos, 178 ± 4 cm, 74 ± 7 kg) e dez não atletas (26 ± 3 anos, 178 ± 6 cm, 79 ± 8 kg) pedalaram em um ciclo ergômetro (CYBEX, The bike,USA) por 30 min a 32oC e 60% de umidade relativa. O esforço estabelecido foi de 10% abaixo do segundo limiar anaeróbico. O suor foi coletado por meio de adesivos absorventes (Tegaderm 3582, 3M, Neuss, Germany) colocados na escápula direita após a limpeza apropriada da pele. Após o término do exercício, os adesivos foram colocados em uma seringa e o suor colocado em um tubo. As concentrações de sódio (Na+), cloro (Cl-) e potássio (K+) no suor foram analisadas através de um seletor de ions (AVL 9180). Média e desvio padrão foram calculados através da estatística descritiva. As diferenças foram estabelecidas usando ANOVA fatorial e teste post hoc de Tukey. A taxa de sudorese foi maior no grupo dos corredores. As concentrações de Na+ e Cl- foram menores no grupo dos corredores do que nos outros grupos. A concentração de K+ não mostrou diferença entre os grupos. As concentrações eletrolíticas do suor dos corredores estão de acordo com os valores previamente publicados para atletas. No entanto, as concentrações de Na+ e Cl- no suor dos nadadores foram similares as dos não atletas, provavelmente porque a regulação da sudorese dentro da água é diferente daquela que ocorre fora dela. / Sweat electrolyte concentration and sweat rate have been reported in athletes trained on land and in nonathletes. Although there is some research on thermoregulatory responses in swimmers, none of them have addressed the sweat electrolyte concentration. The purpose of this study was to compare sweat electrolyte concentration and sweat rate among swimmers runners and non-athletes. Ten swimmers (age 23 ± 3 years, height 179 ± 6 cm, body mass 75 ± 7 kg), 10 runners (age 26 ± 3 years, height 178 ± 4 cm, body mass 74 ± 7 kg) and 10 nonathletes (age 26 ± 3 years, height 178 ± 6 cm, body mass 79 ± 8 kg) cycled on a eletromagnetic-braked ergometer (CYBEX, The bike,USA) for 30 min at 32oC and 60% relative humidity. The work rate was set at 10% below second anaerobic threshold. Sweat was collected by absorbent patches (Tegaderm 3582, 3M, Neuss, Germany) from the scapula. All patches were placed on the right hand side of the body after appropriate cleaning of the skin. After exercise was completed, patches were set into a syringe and sweat was squeezed in a tube. Sweat was analysed for sodium (Na+), cloride (Cl-) and potassium (K+) concentration by ion selector (AVL, 9180). Mean and SD are given as descriptive statistics. Differences were established using ANOVA factorial and Tukey post hoc test. Sweat rate of runners were higher than that of swimmers and nonathletes. Na+ and Cl- concentrations of sweat in the runners group were different from that of the swimmers and nonathletes. K+ concentration did not show difference among the 3 groups. Sweat electrolyte concentrations of runners were within the normal range for athletes. However, sweat Na+ and Cl- concentrations of swimmers were more similar to that of nonatlhetles, and this is probably because regulation of sweating during exercise in water is different from that during exercise on land.

The purpose of this study was to determine the effect of stratum corneum (SC) hydration by distilled water on SC ion content and sweat ion concentrations as measured by occlusive sweat patch. 10 men and 10 women completed approximately 40 minutes of moderate exercise in the heat. Select skin sites were hydrated before sweating by adhering cylinders of distilled water to forearm skin. SC samples were taken before and after exercise using the tape stripping (TS) method and sweat samples were taken with homemade filter paper sweat patches with a tegaderm backing. An increase in SC hydration was verified by a reduction in SC potassium concentration (p<0.05). SC hydration caused a significant decrease in sweat potassium (K+), calcium (Ca++), and lactate (Lac-) concentration: K+ =8.14 ± 0.46 to 6.56 ± 0.46, Ca++ = 0.86 ± 0.17 to 0.67 ± 0.18, Lac- = 11.64 ± 1.36 to 8.82 ± 1.11, euhydrated to hyperhydrated respectively(p<0.05). SC sodium (Na+) and K+ concentration increased after sweating without a sweat patch (p<0.05). Our data do not dispute the idea that electrolytes can be leached from the SC by distilled water or sweat trapped within an occlusive dressing. However, our data indicate that during normal sweating the SC "dehydrates" resulting in an increase in the electrolyte concentration. As such, we propose that the occlusive dressing does trap sweat on the skin but the important end result is that it prevents water movement out of the SC and thereby producing a more concentrated sweat.

During exercise water and electrolytes are lost in sweat. There is a large variation in both sweat rate and sweat composition and as a consequence sweat electrolyte loss can be large, especially for sodium, the primary cation in sweat. The loss of large amounts of sodium in sweat has been linked with hyponatraemia and muscle cramps. Sodium intake is encouraged in some athletes and in some exercise situations, which is in direct contrast to guidelines aimed at the general population aimed at reducing average sodium intakes to 2.4g of sodium per day (6g salt/day). Dietary sodium intakes have been determined by numerous methods, including weighed dietary records and 24h urine collections. As dietary sodium intake in excess of basal requirement is primarily excreted in the urine in non-sweating individuals, and the basal requirement for sodium is small, 24h urine collections can provide an accurate estimate of dietary sodium intake. In Chapter 3, 24h urinary sodium excretion was measured in eighteen subjects on 4 separate occasions. Subjects consumed their normal diet with the exception of a 5g creatine supplement and 500ml of water, which was part of a separate investigation. The relationship between urine sodium excretion in each 24h collection period was weak, but on average males excreted 200 ± 48mmol of sodium per day and females excreted 157 ± 33mmol of sodium per day, which is equivalent to 4.6g and 3.6g of sodium, respectively. This is in excess of the current recommended intake. In chapter 4, the variation in sodium excretion was determined in eight subjects who consumed the same diet for 5 consecutive days. Despite the similar intake of sodium each day, a day to day variation in sodium excretion of 13% was still observed. This was not related to either sodium intake or potassium intake. In chapter 5, nine subjects consumed their normal diet for 5 consecutive days but weighed and recorded all food and drink consumed. During this period, 24h urine samples were also collected. No strenuous exercise was permitted apart from an exercise task on day 4. This involved intermittent cycling in the heat until 2% body mass (BM) was lost. Sweat was collected from four absorbent patches placed on the back, chest, forearm and thigh. Sweat sodium concentration was adjusted to account for the 35% over-estimation using this regional collection method. Subjects lost 1.51 ± 0.19L of sweat and 66 ± 16mmol (range 32 86mmol) of sodium. There was no difference in sodium balance between each 24h period due to a significant decrease in urine sodium excretion on the day of exercise (day 4). In chapter 6, the effect of prior exercise on sweat composition during a second exercise bout completed later that same day was determined. Eight healthy males cycled for 40 minutes in the heat on one or two occasions. A period of 5h elapsed between exercise bouts when two exercise sessions were performed. Sweat was collected using a whole body washdown method and by 4 absorbent patches placed on the back, chest, forearm and thigh. The main finding was that prior exercise did not affect sweat rate or sweat sodium, potassium and chloride concentrations in the second exercise bout when using the whole body washdown method. Chapter 7 determined the effects of two exercise sessions completed on the same day on electrolyte balance. Nine subjects followed their normal dietary behaviour but weighed and recorded all food and drink consumed during 5 consecutive days. During this period 24h urine samples were also collected. No strenuous exercise was permitted during this period apart from two exercise tasks on day 4. During exercise sweat was collected using a whole body washdown technique. Sweat rate and sweat sodium, potassium and chloride concentrations during the second exercise bout were found to be similar to the first exercise bout. Subjects lost 2.64L (range 1.80 3.48L) of sweat and 138 ± 106mmol of sodium (range 32 287mmol). Sodium balance was not significantly affected on the day of exercise, but urine sodium was lower than dietary sodium intake on the day of exercise (Day 4) and the day following exercise (day 5), indicating significant sodium conservation by the kidney. In contrast, no change in sodium intake was observed. In chapter 8, the effect of skimmed milk and a sports drink in restoring fluid balance was examined following exercise-induced dehydration. Seven physically active males cycled intermittently in the heat until 2% BM was lost. During a 1h rehydration period a sports drink (23mmol Na+/L) or skimmed milk (32mmol Na+/L) was consumed in a volume equivalent to 150% of BM loss. Fluid balance at the end of the 3h recovery period tended to be more positive when milk was consumed. Despite this, no difference in exercise capacity in the heat was observed. This thesis shows that exercise did not increase sodium intake, but this may be due to the already high dietary sodium intake of individuals. Sodium balance was maintained in the majority of individuals due to a significant conservation of sodium by the kidneys. When sweat sodium losses are large, urine sodium conservation may not be sufficient to prevent a negative sodium balance. When no food is consumed in the acute period post-exercise, the higher sodium content of skimmed milk than a sports drink may be partly responsible for the increased retention of the ingested fluid. But this did not enhance subsequent performance in the heat.

Introdução: Atualmente, a simpatectomia torácica videoassistida tornou-se o tratamento de escolha para hiperidrose palmar. O principal efeito colateral após operação é a hiperidrose compensatória (HC), sendo considerada a maior causa de insatisfação pelos pacientes. Objetivo: Comparar os resultados obtidos com a simpatectomia torácica videotoracoscópica realizada em dois níveis ganglionares distintos (terceiro versus quarto gânglio torácico) no tratamento da hiperidrose palmo-plantar, por meio de um ensaio clínico randomizado e cego. Método: Foram selecionados 40 pacientes entre fevereiro de 2007 e maio de 2009. Os participantes foram aleatorizados em dois grupos de 20 pacientes (G3 e G4) e submetidos à operação com seguimento de 12 meses (1ª semana, 1° mês, 6° mês e 12° mês). Utilizamos um método objetivo para mensuração do suor, aferindo a TEWL (transepidermal water loss) pelo VapoMeter, além da avaliação da qualidade de vida antes e após a operação. Também foram estudados: resolução da hiperidrose palmar, incidência e intensidade da HC. Resultados: Todos os pacientes apresentaram resolução da hiperidrose palmar após a operação, com diferença estatística em relação ao fator tempo, quando comparados os valores da TEWL palmar no pré-operatório com os seus respectivos valores na 1ª semana, 1° mês, 6° mês e 12° mês. O principal efeito colateral observado foi a hiperidrose compensatória, incidindo com maior frequência no grupo G3 após 12 meses de seguimento; apesar disto, não houve diferença estatística em relação à intensidade (gravidade) da HC nos grupos estudados. Verificou-se melhora da qualidade de vida desde a primeira avaliação do pós-operatório, sem diferença entre os grupos, que assim se manteve até o fim do estudo. As regiões mais acometidas pela HC foram dorso, tórax, abdome e coxas; no entanto, não houve diferença estatística da TEWL mensurada nessas regiões após 12 meses de acompanhamento. Conclusão: Ambas as técnicas foram efetivas no tratamento da hiperidrose palmar, gerando redução objetiva da TEWL independente do gânglio operado. A simpatectomia no nível de G3 apresentou maior incidência de HC; apesar disso, a melhora da qualidade de vida foi similar em ambos os grupos, não existindo diferença significativa da TEWL quantificada no dorso, abdome, coxas e pés após 12 meses / Introduction: Currently, video-assisted thoracic sympathectomy has become the preferred treatment for palmar hyperhidrosis. The main side effect after surgery remains compensatory hyperhidrosis (CH), considered the major cause of dissatisfaction for patients. Objective: To compare the results obtained of video-assisted sympathectomy performed on two distinct ganglion levels (third versus fourth thoracic ganglion) in the treatment of palmo-plantar hyperhidrosis, through a blind randomized clinical trial. Method: We selected 40 patients from February 2007 to May 2009. All participants were randomized into two groups of 20 patients (G3 and G4) and underwent the operation, being followed for 12 months (1 week, 1 month, 6 months and 12th month). We used an objective method for measuring sweat, checking the \"TEWL (transepidermal water loss) measured by the\"VapoMeter\", and evaluated the quality of life before and after the operation. Also studied were: palmar hyperhidrosis, incidence and intensity of the CH. Results: All patients ceased suffering from palmar hyperhidrosis after surgery, with statistical difference regarding the time factor when we compared the values of \"TEWL\" palmar preoperatively with their respective values at 1 week, 1 month, 6 months and 12th month. The main side effect observed was compensatory sweating, most frequent in G3 after 12 months of follow-up; despite this, there was no statistical difference regarding the intensity (severity) of CH in both groups. There was an improvement in quality of life since the first evaluation of the postoperative period, with no difference between groups, and so it remained until the end of follow-up. The areas most affected by CH were back, chest, abdomen and thighs; however, there was no statistical difference in the \"TEWL\" measured in these areas after 12 months of follow-up. Conclusion: Both techniques were effective in the treatment of palmar hyperhidrosis, generating objective reduction of \"TEWL\" regardless of the ganglion operated. Sympathectomy G3 had a higher incidence of CH, yet the improvement in quality of life was similar in both groups without significant differences of \"TEWL\" quantified on the back, abdomen, thighs and legs after 12 months of follow up

by Vincent, Wai-ip Law. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 128-134). / Abstract also in Chinese. / Chapter Chapter I. --- Literature Review / Chapter I.1. --- "Structure, functions and general physiology of equine sweat gland" / Chapter I.1.1. --- Ultrastructure of equine sweat gland --- p.1 / Chapter I.1.2. --- Functions and physiology of equine sweat gland --- p.3 / Chapter I.1.3. --- Experimental studies on equine sweat gland by functional approaches --- p.4 / Chapter I.1.4. --- Hormonal and neuronal regulation of sweat secretion in equidaes --- p.5 / Chapter I.1.5. --- Possible role(s) of extracellular ATP in equine sweat gland epithelia --- p.6 / Chapter I.1.6. --- Measurement of electrogenic anion secretion by short-circuit current (Isc) technique --- p.8 / Chapter I.2. --- Classification of purinergic receptors and its existence in biological systems / Chapter I.2.1. --- Functional classification of purinergic receptors --- p.13 / Chapter I.2.2. --- Basic structure of G-protein coupled P2Y receptors --- p.17 / Chapter I.2.3. --- Physiological function and significance of purinergic receptors --- p.20 / Chapter I.3. --- Objectives of study --- p.22 / Chapter Chapter II. --- Methods and Materials / Chapter II.l. --- Culture technique of the equine epithelial cells --- p.23 / Chapter II.2. --- Conventional short-circuit current (Isc) measurement technique / Chapter II.2.1. --- Introduction --- p.25 / Chapter II.2.2. --- Preparation of permeable supports and electrodes --- p.25 / Chapter II.2.3. --- Experimental set up and measurement of Isc --- p.28 / Chapter II.2.4. --- Measurement of Isc during experiment --- p.30 / Chapter II.3. --- Measurement of intracellular free calcium ( [Ca2+ ]ii) by microspectrofluorimetry / Chapter II.3.1. --- Preparation of cells --- p.31 / Chapter II.3.2. --- The set up and procedures for experiment --- p.31 / Chapter II.4. --- Simultaneous measurement of changes in [Ca2+ ]i and Isc / Chapter II.4.1. --- Experimental set up and manipulation --- p.35 / Chapter II.4.2. --- Other preparations before experiment --- p.37 / Chapter II.5. --- Material and solutions used for experiment / Chapter II.5.1. --- Culture media and enzyme --- p.40 / Chapter II.5.2. --- Chemicals and Drugs --- p.40 / Chapter II.5.3. --- Preparation of solution for experiments --- p.42 / Chapter II.6. --- Statistical analysis --- p.44 / Chapter Chapter III. --- Results / Chapter III.l. --- Effects of nucleotides on transepithelial ion transport / Chapter III.1.1. --- Basic electrophysiological properties of cultured equine sweat gland epithelia --- p.45 / Chapter III. 1.2. --- Short-circuit current (Isc) induced by nucleotides --- p.45 / Chapter III. 1.3. --- Identification of ion species responsible for the change in Isc --- p.50 / Chapter III. 1.4. --- Effects of chloride channels blockers on the UTP-induced Isc --- p.51 / Chapter III.2. --- Signal transduction mechanisms of P2Y-nucleotide receptors / Chapter III.2.1. --- The involvement of Gi-proteins --- p.56 / Chapter III.2.2. --- Effect of BAPTA on the increases in Isc induced by nucleotides --- p.58 / Chapter III.2.3. --- Study of P2Y-receptor mediated increase in [Ca2+]i --- p.62 / Chapter III.3. --- Characterization of the P2Y subtype(s) by cross desensitization experiments / Chapter III.3.1. --- Autologous desensitization experiments --- p.70 / Chapter III.3.2. --- Classical cross desensitization experiments --- p.70 / Chapter III.3.3. --- Characterization of the ATP-insensitive P2Y-receptor --- p.80 / Chapter III.3.4. --- Interaction between ATP and bradykinin --- p.87 / Chapter III.4. --- Simultaneous measurement of [Ca2+]i and Issc / Chapter III.4.1. --- Effect ofUDP and ADP --- p.89 / Chapter III.4.2. --- Correlation of Isc and [Ca2+]i --- p.92 / Chapter III.4.3. --- Cross desensitization experiments --- p.97 / Chapter III.5. --- Evidence of a [Ca2+]i-independent Isc-component induced by nucleotides / Chapter III.5.1. --- The time course of the ΔRf and ΔISC --- p.102 / Chapter III.5.2. --- Effect of ionomycin on the ΔISC and ΔRf induced by nucleotides --- p.110 / Chapter III.5.3. --- Effect of thapsigargin on the ΔISC and ΔRf induced by nucleotides --- p.110 / Chapter III.5.4. --- Effect of thapsigargin in nominal Ca2+-free solution --- p.115 / Chapter Chapter IV. --- Discussion / Chapter IV. 1. --- Role of extracellular nucleotides in epithelial tissues --- p.119 / Chapter IV.2. --- Characterization of an ATP-insensitive P2Y-nucleotide receptor --- p.120 / Chapter IV.3. --- Expression of the novel ATP-insensitive receptor on a functionally polarized epithelia --- p.122 / Chapter IV.4. --- Involvement of a [Ca2+]i -independent Isc induced by nucleotides --- p.124 / Chapter Chapter V. --- References --- p.128

Introdução: Apesar da falta de evidência cientifica, costuma-se pensar que crianças obesas apresentam desvantagens e são menos tolerantes ao se exercitarem no calor. Objetivo: Comparar a sudorese, balanço hidro-eletrolítico e a tolerância ao exercício no calor entre meninos pré-púberes obesos e eutróficos que pedalam no calor. Métodos: Trinta meninos pré-púberes foram alocados para o grupo de obesos (GO, n=15) e eutróficos (GE, n=15). Após uma sessão de avaliação, os meninos vieram ao laboratório para a sessão de exercício no calor (35C, 40-45%UR). Eles pedalavam por 30 minutos a 50-60% do seu VO2pico pré determinado. Para coletar o suor, adesivos foram fixados sobre 4 regiões da pele (costas, peito, antebraço e coxa) e as amostras foram analisadas para eletrólitos (AVL, 9180). Após o exercício, amostras de urina foram coletadas para análise de volume e eletrólitos para coleta regional de suor (AVL, 9180). Após a pedalada, os meninos descansaram por 10 min e pedalaram a 90% do VO2pico até a exaustão e o tempo de desempenho foi registrado. Durante a sessão, a ingestão “ad libitum” de uma bebida esportiva foi avaliada. Sensação subjetiva de calor foi avaliada durante toda a sessão. Resultados: A taxa de sudorese relativa a área de superfície corporal foi similar entre eutróficos e obesos (488  232 e 417  89.6 ml.m2.min-1, respectively; p=0,004) e as [Na+] e [Cl-] no suor foram maiores nos meninos obesos (p=0,005), enquanto a [K+] foi similar entre os grupos (p = 0,004). Ambos os grupos apresentaram um balanço hidroeletrolítico negativo, mas não existiu diferença entre os grupos. O tempo de desempenho foi maior no GE (89.6  64.1) que o GO (41.2  29.6 seg; p=0,005). A sensação subjetiva de calor foi maior no GO que no GE em todos os momentos (p = 0,005). Conclusão: Meninos pré-púberes obesos apresentaram uma similar taxa de sudorese relativa à área de superfície corporal, menor tolerância ao exercício no calor, e maior [Na+] e [Cl-] no suor comparado aos eutróficos. Crianças obesas não diferem das eutróficas em relação ao balanço hidroeletrolítico. / Introduction: Despite the lack of scientific evidence, it is generally thought that obese children have disadvantages and are less tolerant to exercise in the heat when compared to lean children. Purpose: To compare sweating, water and electrolyte balance, and exercise tolerance heat between obese and lean boys who cycled in the heat. Methods: Thirty prepubertal boys formed an obese (OG, n=15) and a lean (LG, n=15) group. After a screening session and evaluation of physical characteristics and VO2peak, the boys came to the laboratory for the exercise session in the heat (35C, 40-45%RU). They cycled for 30 minutes at 50-60% of their pre-determined VO2peak. To collect sweat, patches were attached on 4 regions of the skin (back, chest, forearm and thigh) and samples were analyzed for electrolytes (AVL 9180). After exercise, urine samples were collected for volume and electrolyte analyses (AVL 9180). After this cycling, the boys rested 10 min and cycled at 90% VO2peak until exhaustion and the performance time was registered. During the whole session, a sports drink was available to drink “ad libitum” and the intake was registered. Heat subject sensation (HSS) was evaluated during the whole session. Results: Sweat rate relative to body surface area was similar between lean and obesity boys (488  232 and 417  89.6 ml.m2.min-1, respectively; p=0.004) and sweat [Na+] and [Cl-] were higher in the obese boys (p=0.005), whereas [K+] was similar between groups (p = 0.004). Both groups showed a negative water and electrolyte balance, but there was no difference between groups. The performance time was longer in the LG (89.6  64.1) than OG (41.2  29.6 sec; p=0.005). The heat subjective sensation was higher in GO than in GE at all times (p = 0.005). Conclusion: Obese prepubescent boys showed similar sweat rate relative to body surface area, lower exercise heat tolerance, and increased [Na+] and [Cl-] sweat loss compared to lean children. Obese children did not differ from lean children related to water and electrolyte balance.

Introdução: Atualmente, a simpatectomia torácica videoassistida tornou-se o tratamento de escolha para hiperidrose palmar. O principal efeito colateral após operação é a hiperidrose compensatória (HC), sendo considerada a maior causa de insatisfação pelos pacientes. Objetivo: Comparar os resultados obtidos com a simpatectomia torácica videotoracoscópica realizada em dois níveis ganglionares distintos (terceiro versus quarto gânglio torácico) no tratamento da hiperidrose palmo-plantar, por meio de um ensaio clínico randomizado e cego. Método: Foram selecionados 40 pacientes entre fevereiro de 2007 e maio de 2009. Os participantes foram aleatorizados em dois grupos de 20 pacientes (G3 e G4) e submetidos à operação com seguimento de 12 meses (1ª semana, 1° mês, 6° mês e 12° mês). Utilizamos um método objetivo para mensuração do suor, aferindo a TEWL (transepidermal water loss) pelo VapoMeter, além da avaliação da qualidade de vida antes e após a operação. Também foram estudados: resolução da hiperidrose palmar, incidência e intensidade da HC. Resultados: Todos os pacientes apresentaram resolução da hiperidrose palmar após a operação, com diferença estatística em relação ao fator tempo, quando comparados os valores da TEWL palmar no pré-operatório com os seus respectivos valores na 1ª semana, 1° mês, 6° mês e 12° mês. O principal efeito colateral observado foi a hiperidrose compensatória, incidindo com maior frequência no grupo G3 após 12 meses de seguimento; apesar disto, não houve diferença estatística em relação à intensidade (gravidade) da HC nos grupos estudados. Verificou-se melhora da qualidade de vida desde a primeira avaliação do pós-operatório, sem diferença entre os grupos, que assim se manteve até o fim do estudo. As regiões mais acometidas pela HC foram dorso, tórax, abdome e coxas; no entanto, não houve diferença estatística da TEWL mensurada nessas regiões após 12 meses de acompanhamento. Conclusão: Ambas as técnicas foram efetivas no tratamento da hiperidrose palmar, gerando redução objetiva da TEWL independente do gânglio operado. A simpatectomia no nível de G3 apresentou maior incidência de HC; apesar disso, a melhora da qualidade de vida foi similar em ambos os grupos, não existindo diferença significativa da TEWL quantificada no dorso, abdome, coxas e pés após 12 meses / Introduction: Currently, video-assisted thoracic sympathectomy has become the preferred treatment for palmar hyperhidrosis. The main side effect after surgery remains compensatory hyperhidrosis (CH), considered the major cause of dissatisfaction for patients. Objective: To compare the results obtained of video-assisted sympathectomy performed on two distinct ganglion levels (third versus fourth thoracic ganglion) in the treatment of palmo-plantar hyperhidrosis, through a blind randomized clinical trial. Method: We selected 40 patients from February 2007 to May 2009. All participants were randomized into two groups of 20 patients (G3 and G4) and underwent the operation, being followed for 12 months (1 week, 1 month, 6 months and 12th month). We used an objective method for measuring sweat, checking the \"TEWL (transepidermal water loss) measured by the\"VapoMeter\", and evaluated the quality of life before and after the operation. Also studied were: palmar hyperhidrosis, incidence and intensity of the CH. Results: All patients ceased suffering from palmar hyperhidrosis after surgery, with statistical difference regarding the time factor when we compared the values of \"TEWL\" palmar preoperatively with their respective values at 1 week, 1 month, 6 months and 12th month. The main side effect observed was compensatory sweating, most frequent in G3 after 12 months of follow-up; despite this, there was no statistical difference regarding the intensity (severity) of CH in both groups. There was an improvement in quality of life since the first evaluation of the postoperative period, with no difference between groups, and so it remained until the end of follow-up. The areas most affected by CH were back, chest, abdomen and thighs; however, there was no statistical difference in the \"TEWL\" measured in these areas after 12 months of follow-up. Conclusion: Both techniques were effective in the treatment of palmar hyperhidrosis, generating objective reduction of \"TEWL\" regardless of the ganglion operated. Sympathectomy G3 had a higher incidence of CH, yet the improvement in quality of life was similar in both groups without significant differences of \"TEWL\" quantified on the back, abdomen, thighs and legs after 12 months of follow up