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Differential right and left ventricular diastolic tolerance to acute afterload and NCX gene expression in Wistar rats
| Resumo: | This study evaluated right ventricular (RV) and left ventricular (LV) diastolic tolerance to afterload and SERCA2a, phospholamban and sodium-calcium exchanger (NCX) gene expression in Wistar rats. Time constant tau and end-diastolic pressure-dimension relation (EDPDR) were analyzed in response to progressive RV or LV afterload elevations, induced by beat-to-beat pulmonary trunk or aortic root constrictions, respectively. Afterload elevations decreased LV-tau, but increased RV-tau. Whereas LV-tau analyzed the major course of pressure fall, RV-tau only assessed the last fourth. Furthermore, RV afterload elevations progressively upward shifted RV-EDPDR, whilst LV afterload elevations did not change LV-EDPDR. SERCA2a and phospholamban mRNA were similar in both ventricles. NCX-mRNA was almost 50% lower in RV than in LV. Left ventricular afterload elevations, therefore, accelerated the pressure fall and did not induce diastolic dysfunction, indicating high LV diastolic tolerance to afterload. On the contrary, RV afterload elevations decelerated the late RV pressure fall and induced diastolic dysfunction, indicating small RV diastolic tolerance to afterload. These results support previous findings relating NCX with late Ca2+ reuptake, late relaxation and diastolic dysfunction. |
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| Assunto: | Medical and Health sciences Ciências médicas e da saúde |
| País: | Portugal |
| Tipo de documento: | journal article |
| Tipo de acesso: | Aberto |
| Instituição associada: | Repositório Aberto da Universidade do Porto |
| Idioma: | inglês |
| Origem: | Repositório Aberto da Universidade do Porto |
| _version_ | 1850560636124135424 |
|---|---|
| conditionsOfAccess_str | open access |
| contentURL_str_mv | https://repositorio-aberto.up.pt/handle/10216/67225 |
| country_str | PT |
| description | This study evaluated right ventricular (RV) and left ventricular (LV) diastolic tolerance to afterload and SERCA2a, phospholamban and sodium-calcium exchanger (NCX) gene expression in Wistar rats. Time constant tau and end-diastolic pressure-dimension relation (EDPDR) were analyzed in response to progressive RV or LV afterload elevations, induced by beat-to-beat pulmonary trunk or aortic root constrictions, respectively. Afterload elevations decreased LV-tau, but increased RV-tau. Whereas LV-tau analyzed the major course of pressure fall, RV-tau only assessed the last fourth. Furthermore, RV afterload elevations progressively upward shifted RV-EDPDR, whilst LV afterload elevations did not change LV-EDPDR. SERCA2a and phospholamban mRNA were similar in both ventricles. NCX-mRNA was almost 50% lower in RV than in LV. Left ventricular afterload elevations, therefore, accelerated the pressure fall and did not induce diastolic dysfunction, indicating high LV diastolic tolerance to afterload. On the contrary, RV afterload elevations decelerated the late RV pressure fall and induced diastolic dysfunction, indicating small RV diastolic tolerance to afterload. These results support previous findings relating NCX with late Ca2+ reuptake, late relaxation and diastolic dysfunction. |
| documentTypeURL_str | http://purl.org/coar/resource_type/c_6501 |
| documentType_str | journal article |
| id | 46c5d0cc-9a97-4e01-9471-0d40870801ab |
| language | eng |
| relatedInstitutions_str_mv | Repositório Aberto da Universidade do Porto |
| resourceName_str | Repositório Aberto da Universidade do Porto |
| spellingShingle | Differential right and left ventricular diastolic tolerance to acute afterload and NCX gene expression in Wistar rats Medical and Health sciences Ciências médicas e da saúde |
| title | Differential right and left ventricular diastolic tolerance to acute afterload and NCX gene expression in Wistar rats |
| topic | Medical and Health sciences Ciências médicas e da saúde |