Environmental factors such as ambient temperature and oxygen availability are variation in different altitude. Individuals within a species, living in variable environments often display phenotypic plasticity by changing morphology, behavior, reproduction, and physiology to meet the individual¡¦s ability to survive demanding conditions. This study was aimed to investigate the expression of angiotensin receptor and nitric oxide synthase genes of individuals resided at differential altitude, in an attempt to find the role of these molecules in cardiovascular adaptation to altitude. Spiny rats (Niviventer coxingi) are widely elevational distributed in Taiwan. They were studied under more natural conditions to provide an ecological context data on physiological plasticity between the different altitudes. I examined the body weight, blood pressure, heart rate and the expression of angiotensin type 1 or type 2 (ATI or ATII) receptor and nitric oxide synthase (NOS) genes in tissues (cortex, hypothalamus, medulla, lung, heart, aorta, adrenal gland and kidney) of spiny rats resided at differential altitude and during the domesticated period. The results of the study showed that spiny rats resided at higher altitudes were lighter than that at lower altitudes (750 m: 178.6¡Ó35.8 g and 1600 m: 122.3¡Ó29.3 g). Spiny rats resided at 1600 m did not change their body weight during the domesticated period, but rats resided at 750 m gradually reduced their body weight. Blood pressure and heart rate were similar between rats resided at different altitudes, and did not change during the domesticated period. ATI receptor, endothelelial NOS (eNOS), inducible NOS (iNOS) and neuronal NOS (nNOS) mRNA expression in these tissues were similar between rats resided at different altitudes. ATII receptor mRNA expressed in these tissues under our detection limit. Rats resided at 750 m declined the level of nNOS in heart, when they were domesticated at 100 m. ATI receptor in kidney reduced at first, but subsequently increase to same level like native. Moreover, rats resided at 1600 m declined the level of iNOS in heart, when they were domesticated at 100 m. Together, these results indicate that heart rate, blood pressure, ATI receptor, eNOS, iNOS and nNOS mRNA expressions in these tissues were similar between rats resided at different altitudes. If there was no other compensatory mechanism, individuals resided at higher altitude were limited in low available oxygen. A reduced body weight could help in adaptation to high-altitude.

Cardiovascular complications represent the leading cause of death in chronic kidney disease (CKD) patients. Significant renal mass reduction induced by 5/6 subtotal nephrectomy (Nx) animal model leads to a chain of events that culminates in hypertension and CKD. The renin angiotensin (Ang) system (RAS) is known to be dysregulated, specifically Ang type 1 receptor (AT1R) plays a major role in development and progression of the disease. However, conflicting results have been reported on intrarenal AT1R levels, and the impact of antihypertensive drugs on RAS signaling is divergent. We hypothesize that PET imaging will be able to quantify kidney AT1R expression reliably in healthy and disease states. The broad objectives of this research project were: (i) to develop a positron emission tomography (PET) probe capable of detecting changes in the AT1R binding in the kidney; (ii) to elucidate the nature/temporal role of renal AT1R in Nx rat model of CKD; and (iii) to explore the predictive value of non-invasive PET imaging of AT1R to guide the use of antihypertensive therapy in preventing the progression of the disease. The novel selective AT1R PET radioligand [18F]FPyKYNE-losartan was successfully used with PET in detecting renal AT1Rs at early and late stages of the CKD. The PET results correlated well with in vitro [125I]-[Sar1, Ile8]Ang II autoradiography. Over the time-course of the study (10-20 weeks), the Nx rats exhibited renal impairment, proteinuria and sustained hypertension. Echocardiography indicated the development of cardiac hypertrophy most likely secondary to the hyperdynamic circulation. These abnormalities were associated with increasing plasma and kidney levels of Ang II, and compensatory downregulation of renal AT1Rs. ACEI enalapril attenuated renal impairment, hypertension and prevented progression of cardiac hypertrophy in Nx rats. This was successfully accomplished through reduction of systemic and kidney Ang II, and consequent normalization of renal AT1R as measured by PET (and autoradiography). The non-dihydropyridine CCB diltiazem also reduced blood pressure but did not normalize renal AT1R expression. Diltiazem induced elevation in Ang II levels in plasma, kidney and heart, associated with exacerbation of renal and cardiac dysfunction, and no change in AT1R renal expression. This outcome adds value to the use of [18F]FPyKYNE-losartan PET for determination of receptor abnormalities with progression of the disease and monitoring of therapy.

Introdução: A presença de anticorpos (Ac) anti-HLA específicos contra o doador representam um potencial risco para o desenvolvimento de rejeição do enxerto pulmonar. Apesar de existirem evidências sobre a importância de anticorpos anti-receptor de tipo 1 da angiotensina II (AT1R) para a sobrevida do enxerto a longo prazo em transplante de rim e coração, não existe qualquer informação da sua frequência e relação com bronquiolite obliterante no transplante de pulmão. Objetivos: Descrever a freqüência e o impacto da presença de Ac anti-AT1R para o desenvolvimento de bronquiolite obliterante (BO) após o transplante pulmonar. Pacientes e Métodos: Foram alocados 50 pacientes com mais de seis meses de transplante, em acompanhamento ambulatorial. Uma alíquota de soro pré-transplante e outra colhida no momento da alocação foram testadas para a presença de Ac anti-HLA e anti-MICA em plataforma Luminex® e anti-AT1R (AT1R) por ELISA,. O acompanhamento médio foi de 78,3 meses. Foram avaliadas as características e desfechos clínicos, bem como o tempo de sobrevida para o desenvolvimento de BO. Os pacientes que nunca desenvolveram anti-AT1R foram comparados com aqueles que tinham o Ac pré-formado ou que o desenvolveram após o transplante. Foi utilizada a curva de sobrevida de Kaplan-Meier, reverse censoring method, log-rank e regressão de Cox (anti-HLA, anti-MICA, infecção por CMV e rejeição aguda). Os resultados foram descritos como risco relativo (RR) e intervalos de confiança (IC) de 95%, sendo significativos os valores de P<0,05. Resultados: A prevalência de anti-AT1R pré-formado foi de 22% e de novo 15,3%. Não se demonstrou associação entre anti-AT1R e anti-HLA pré-formados (P=0,279;1,1[0,8 a 1,7]), com tendência de associação com anti-HLA positivo pós transplante (P=0,063;1,3[0,9 a 1,8]). Cinquenta por cento (4/8) dos receptores por bronquiolite viral tinham anti-AT1R pré-formado, comparados a 16,7% (7/42) dos transplantados por outra patologia (P=0,037; 1,7 [0,8 a 3,4]), sem associação com anti-HLA (P=0,716) e anti-MICA (P=0,659) pré-formados. Nenhum paciente com linfangioliomiomatose (LAM) apresentou anti-AT1R pré ou pós-transplante. O RR para o desenvolvimento de BO comparando-se pacientes com anti-AT1R àqueles que nunca manifestaram o Ac foi de 1,50 (0,72 a 3,14) [P = 0,282]. Conclusão: Há uma tendência mostrando a associação entre a presença de anti-AT1R e o desenvolvimento de BO após o transplante pulmonar. A doença pulmonar de base parece ter implicação no desenvolvimento de anti-AT1R, sendo a que bronquiolite obliterante viral mostra maior risco para seu aparecimento enquanto a LAM risco mínimo. / Introduction: The presence of specific anti-HLA antibodies (Ab) against organ donors represent a potential risk for the development of rejection in lung grafts. There are consistent evidences about the importance of the anti-receptor for angiotensin II type 1 (AT1R) for long-term graft survival in kidney and heart transplantation. However, there is no information about AT1R in lung transplantation and its relationship with bronchiolitis obliterans. Objectives: The aim of this study was to describe the frequency and impact of the presence of anti-Ac AT1R for the development of bronchiolitis obliterans (BO) after lung transplantation. Patients and Methods: We studied fifty patients after six months of transplantation. All patients had an aliquot of pre-transplantation serum and other sample at the time of their selection for the study. The serum was tested for the presence of Ab anti-HLA and anti-MICA in a Luminex platform® and anti-AT1R (AT1R) by ELISA,. The mean followup was 78.3 months. We analyzed the clinical characteristics and outcomes and also survival time for the development of BO. We compared the patients who never developed anti-AT1R with those who had the preformed antibody or developed it after transplantation. We applied the survival curve of Kaplan-Meier, reverse censoring method, log-rank and Cox regression (anti-HLA anti-MICA, CMV infection and acute rejection). The results were described as relative risk (RR) and confidence intervals (CI) of 95%, with significant P values <0.05. Results: The prevalence of preformed anti-AT1R was 22% and 15,3% de novo. There were no association between preformed anti-AT1R and anti-HLA (P = 0.279, 1.1 [0.8 to 1.7]), with a trend of association with positive anti-HLA post transplantation (P = 0.063; 1.3 [0.9 to 1.8]). Fifty percent (4/8) of the receptors for viral bronchiolitis (BOV) had preformed anti-AT1R, compared to 16.7% (7/42) of the all transplanted patientes for other diseases (P = 0.037, 1.7 [0 8 to 3.4]). There were no association with preformed anti-HLA (P = 0.716) and anti-MICA (P = 0.659). No patients with lymphangioleiomyomatosis (LAM) had anti-AT1R pre-or post-transplant. The relative risk for developing BO when comparing patients with anti-AT1R to those who never expressed antibodies was 1.50 (0.72 to 3.14) [P = 0.282]. Conclusion: There is a trend showing the association between the presence of anti-AT1R and developing BO after lung transplantation. The underlying lung disease seems to have implications in developing anti-AT1R, and viral bronchiolitis obliterans that shows higher risk for onset while LAM minimum risk.

Introdução: A presença de anticorpos (Ac) anti-HLA específicos contra o doador representam um potencial risco para o desenvolvimento de rejeição do enxerto pulmonar. Apesar de existirem evidências sobre a importância de anticorpos anti-receptor de tipo 1 da angiotensina II (AT1R) para a sobrevida do enxerto a longo prazo em transplante de rim e coração, não existe qualquer informação da sua frequência e relação com bronquiolite obliterante no transplante de pulmão. Objetivos: Descrever a freqüência e o impacto da presença de Ac anti-AT1R para o desenvolvimento de bronquiolite obliterante (BO) após o transplante pulmonar. Pacientes e Métodos: Foram alocados 50 pacientes com mais de seis meses de transplante, em acompanhamento ambulatorial. Uma alíquota de soro pré-transplante e outra colhida no momento da alocação foram testadas para a presença de Ac anti-HLA e anti-MICA em plataforma Luminex® e anti-AT1R (AT1R) por ELISA,. O acompanhamento médio foi de 78,3 meses. Foram avaliadas as características e desfechos clínicos, bem como o tempo de sobrevida para o desenvolvimento de BO. Os pacientes que nunca desenvolveram anti-AT1R foram comparados com aqueles que tinham o Ac pré-formado ou que o desenvolveram após o transplante. Foi utilizada a curva de sobrevida de Kaplan-Meier, reverse censoring method, log-rank e regressão de Cox (anti-HLA, anti-MICA, infecção por CMV e rejeição aguda). Os resultados foram descritos como risco relativo (RR) e intervalos de confiança (IC) de 95%, sendo significativos os valores de P<0,05. Resultados: A prevalência de anti-AT1R pré-formado foi de 22% e de novo 15,3%. Não se demonstrou associação entre anti-AT1R e anti-HLA pré-formados (P=0,279;1,1[0,8 a 1,7]), com tendência de associação com anti-HLA positivo pós transplante (P=0,063;1,3[0,9 a 1,8]). Cinquenta por cento (4/8) dos receptores por bronquiolite viral tinham anti-AT1R pré-formado, comparados a 16,7% (7/42) dos transplantados por outra patologia (P=0,037; 1,7 [0,8 a 3,4]), sem associação com anti-HLA (P=0,716) e anti-MICA (P=0,659) pré-formados. Nenhum paciente com linfangioliomiomatose (LAM) apresentou anti-AT1R pré ou pós-transplante. O RR para o desenvolvimento de BO comparando-se pacientes com anti-AT1R àqueles que nunca manifestaram o Ac foi de 1,50 (0,72 a 3,14) [P = 0,282]. Conclusão: Há uma tendência mostrando a associação entre a presença de anti-AT1R e o desenvolvimento de BO após o transplante pulmonar. A doença pulmonar de base parece ter implicação no desenvolvimento de anti-AT1R, sendo a que bronquiolite obliterante viral mostra maior risco para seu aparecimento enquanto a LAM risco mínimo. / Introduction: The presence of specific anti-HLA antibodies (Ab) against organ donors represent a potential risk for the development of rejection in lung grafts. There are consistent evidences about the importance of the anti-receptor for angiotensin II type 1 (AT1R) for long-term graft survival in kidney and heart transplantation. However, there is no information about AT1R in lung transplantation and its relationship with bronchiolitis obliterans. Objectives: The aim of this study was to describe the frequency and impact of the presence of anti-Ac AT1R for the development of bronchiolitis obliterans (BO) after lung transplantation. Patients and Methods: We studied fifty patients after six months of transplantation. All patients had an aliquot of pre-transplantation serum and other sample at the time of their selection for the study. The serum was tested for the presence of Ab anti-HLA and anti-MICA in a Luminex platform® and anti-AT1R (AT1R) by ELISA,. The mean followup was 78.3 months. We analyzed the clinical characteristics and outcomes and also survival time for the development of BO. We compared the patients who never developed anti-AT1R with those who had the preformed antibody or developed it after transplantation. We applied the survival curve of Kaplan-Meier, reverse censoring method, log-rank and Cox regression (anti-HLA anti-MICA, CMV infection and acute rejection). The results were described as relative risk (RR) and confidence intervals (CI) of 95%, with significant P values <0.05. Results: The prevalence of preformed anti-AT1R was 22% and 15,3% de novo. There were no association between preformed anti-AT1R and anti-HLA (P = 0.279, 1.1 [0.8 to 1.7]), with a trend of association with positive anti-HLA post transplantation (P = 0.063; 1.3 [0.9 to 1.8]). Fifty percent (4/8) of the receptors for viral bronchiolitis (BOV) had preformed anti-AT1R, compared to 16.7% (7/42) of the all transplanted patientes for other diseases (P = 0.037, 1.7 [0 8 to 3.4]). There were no association with preformed anti-HLA (P = 0.716) and anti-MICA (P = 0.659). No patients with lymphangioleiomyomatosis (LAM) had anti-AT1R pre-or post-transplant. The relative risk for developing BO when comparing patients with anti-AT1R to those who never expressed antibodies was 1.50 (0.72 to 3.14) [P = 0.282]. Conclusion: There is a trend showing the association between the presence of anti-AT1R and developing BO after lung transplantation. The underlying lung disease seems to have implications in developing anti-AT1R, and viral bronchiolitis obliterans that shows higher risk for onset while LAM minimum risk.

Introdução: A presença de anticorpos (Ac) anti-HLA específicos contra o doador representam um potencial risco para o desenvolvimento de rejeição do enxerto pulmonar. Apesar de existirem evidências sobre a importância de anticorpos anti-receptor de tipo 1 da angiotensina II (AT1R) para a sobrevida do enxerto a longo prazo em transplante de rim e coração, não existe qualquer informação da sua frequência e relação com bronquiolite obliterante no transplante de pulmão. Objetivos: Descrever a freqüência e o impacto da presença de Ac anti-AT1R para o desenvolvimento de bronquiolite obliterante (BO) após o transplante pulmonar. Pacientes e Métodos: Foram alocados 50 pacientes com mais de seis meses de transplante, em acompanhamento ambulatorial. Uma alíquota de soro pré-transplante e outra colhida no momento da alocação foram testadas para a presença de Ac anti-HLA e anti-MICA em plataforma Luminex® e anti-AT1R (AT1R) por ELISA,. O acompanhamento médio foi de 78,3 meses. Foram avaliadas as características e desfechos clínicos, bem como o tempo de sobrevida para o desenvolvimento de BO. Os pacientes que nunca desenvolveram anti-AT1R foram comparados com aqueles que tinham o Ac pré-formado ou que o desenvolveram após o transplante. Foi utilizada a curva de sobrevida de Kaplan-Meier, reverse censoring method, log-rank e regressão de Cox (anti-HLA, anti-MICA, infecção por CMV e rejeição aguda). Os resultados foram descritos como risco relativo (RR) e intervalos de confiança (IC) de 95%, sendo significativos os valores de P<0,05. Resultados: A prevalência de anti-AT1R pré-formado foi de 22% e de novo 15,3%. Não se demonstrou associação entre anti-AT1R e anti-HLA pré-formados (P=0,279;1,1[0,8 a 1,7]), com tendência de associação com anti-HLA positivo pós transplante (P=0,063;1,3[0,9 a 1,8]). Cinquenta por cento (4/8) dos receptores por bronquiolite viral tinham anti-AT1R pré-formado, comparados a 16,7% (7/42) dos transplantados por outra patologia (P=0,037; 1,7 [0,8 a 3,4]), sem associação com anti-HLA (P=0,716) e anti-MICA (P=0,659) pré-formados. Nenhum paciente com linfangioliomiomatose (LAM) apresentou anti-AT1R pré ou pós-transplante. O RR para o desenvolvimento de BO comparando-se pacientes com anti-AT1R àqueles que nunca manifestaram o Ac foi de 1,50 (0,72 a 3,14) [P = 0,282]. Conclusão: Há uma tendência mostrando a associação entre a presença de anti-AT1R e o desenvolvimento de BO após o transplante pulmonar. A doença pulmonar de base parece ter implicação no desenvolvimento de anti-AT1R, sendo a que bronquiolite obliterante viral mostra maior risco para seu aparecimento enquanto a LAM risco mínimo. / Introduction: The presence of specific anti-HLA antibodies (Ab) against organ donors represent a potential risk for the development of rejection in lung grafts. There are consistent evidences about the importance of the anti-receptor for angiotensin II type 1 (AT1R) for long-term graft survival in kidney and heart transplantation. However, there is no information about AT1R in lung transplantation and its relationship with bronchiolitis obliterans. Objectives: The aim of this study was to describe the frequency and impact of the presence of anti-Ac AT1R for the development of bronchiolitis obliterans (BO) after lung transplantation. Patients and Methods: We studied fifty patients after six months of transplantation. All patients had an aliquot of pre-transplantation serum and other sample at the time of their selection for the study. The serum was tested for the presence of Ab anti-HLA and anti-MICA in a Luminex platform® and anti-AT1R (AT1R) by ELISA,. The mean followup was 78.3 months. We analyzed the clinical characteristics and outcomes and also survival time for the development of BO. We compared the patients who never developed anti-AT1R with those who had the preformed antibody or developed it after transplantation. We applied the survival curve of Kaplan-Meier, reverse censoring method, log-rank and Cox regression (anti-HLA anti-MICA, CMV infection and acute rejection). The results were described as relative risk (RR) and confidence intervals (CI) of 95%, with significant P values <0.05. Results: The prevalence of preformed anti-AT1R was 22% and 15,3% de novo. There were no association between preformed anti-AT1R and anti-HLA (P = 0.279, 1.1 [0.8 to 1.7]), with a trend of association with positive anti-HLA post transplantation (P = 0.063; 1.3 [0.9 to 1.8]). Fifty percent (4/8) of the receptors for viral bronchiolitis (BOV) had preformed anti-AT1R, compared to 16.7% (7/42) of the all transplanted patientes for other diseases (P = 0.037, 1.7 [0 8 to 3.4]). There were no association with preformed anti-HLA (P = 0.716) and anti-MICA (P = 0.659). No patients with lymphangioleiomyomatosis (LAM) had anti-AT1R pre-or post-transplant. The relative risk for developing BO when comparing patients with anti-AT1R to those who never expressed antibodies was 1.50 (0.72 to 3.14) [P = 0.282]. Conclusion: There is a trend showing the association between the presence of anti-AT1R and developing BO after lung transplantation. The underlying lung disease seems to have implications in developing anti-AT1R, and viral bronchiolitis obliterans that shows higher risk for onset while LAM minimum risk.

The physiological responses of angiotensin II (Ang II) are mediated across the cell membrane through the angiotensin II type 1 receptor (AT1R), a heptahelical membrane protein coupled to trimeric G-proteins on the cytosolic side. AT1R on binding its ligand, Ang II, leads to downregulation of cell-surface receptor and also its mRNA. We have investigated whether the 3'- and 5'-untranslated regions of the human AT1R mRNA mediate the degradation of hAT1R mRNA by post-transcriptional mechanisms in human adrenocortical carcinoma cell line (H295R cells). Protein kinase C (PKC) activator, phorbol-12-myristate-13-acetate (PMA), showed that the downregulation of hAT1R mRNA is mediated by the PKC pathway. Experiments performed in the presence of cycloheximide and/or Ang II demonstrated that protein translation is essential for hAT1R mRNA downregulation. In vitro cell-free RNA degradation assays did not show any increase in the rate of degradation of in vitro transcribed RNA in the presence of cytoplasmic extract from cells treated with Ang II, which suggested that hAT1R steady state mRNA levels may not be mediated by changes in mRNA degradation rates. Luciferase assay after transient transfection of chimeric plasmids of luciferase and hAT1R-3'-UTR showed that Ang II stabilizes the mRNA rather than increase the rate of degradation. Similar results were observed in Northern blot experiments utilizing beta-globin fusion with 3'-UTR that led to stabilization of the chimeric mRNA. Luciferase fusion constructs with both 5'- and 3'-UTRs demonstrated that UTRs are not involved in the Ang II-mediated degradation of hAT1R mRNA. Experiments using transcriptional inhibitor actinomycin D demonstrated that the hAT1R mRNA is not destabilized in response to Ang II activation in H295R cells. Nuclear run-on assay performed in the adrenocortical carcinoma cells demonstrated that the Ang II-stimulated downregulation of hAT1R is mediated by transcriptional inhibition. The transcription of hAT1R mRNA was reduced by 44 and 70% after Ang II treatment for 1 and 2 hours, respectively. Taken together, these findings suggest that the Ang II-induced downregulation of hAT1R steady state mRNA levels is transcriptionally controlled and is not mediated by post-transcriptional mechanisms.