spr-measuring instrument  (Biacore)

Journal: Pulmonary Circulation

Article Title: Understanding longitudinal biventricular structural and functional changes in a pulmonary hypertension Sugen–hypoxia rat model by cardiac magnetic resonance imaging

doi: 10.1177/2045894019897513

Figure Lengend Snippet: Right ventricular systolic pressure measured by right heart catheterization (a), RV/(LV + septum) by gross weight (b), the percentage of remodeled vessels in a lung section (c), and immunohistochemical analysis of α-smooth muscle actin (α-SMA) staining in the smooth muscle layer of small pulmonary arteries of the lungs ((d) to (g)). For right heart pressure analysis, the catheter was inserted into the jugular vein and guided into the right ventricle to measure right ventricular systolic pressure (RVSP). Animals were culled, the heart was isolated, atria were removed and RV/(LV + septum) were measured to assess RV hypertrophy. Although there are significant differences between the normoxic group ( n = 8) and Sugen–hypoxic groups at five ( n = 4) and eight weeks ( n = 4), there were no significant differences in RVSP nor RV/(LV + septum) at autopsy between Sugen–hypoxia five and eight weeks. Vascular thickening was determined by smooth muscle actin antibody (ab5694, Abcam, Cambridge, UK) staining, thickening was characterized by an increase in the vessel wall diameter of more than 50% of the arterial wall or complete occlusion. The number of remodeled vessels over the total number of vessels present in a lung section was determined. Results are shown as mean ± SEM. ANOVA test was used to compare the three groups, and if there was statistical significance, a Tukey HSD test was used for post hoc analysis. * represents p < 0.05 and ** represents p < 0.01. For immunohistochemical analysis of α-smooth muscle actin (α-SMA) staining in the smooth muscle layer of small pulmonary arteries of the lung, sections were viewed at ×200. (d) and (f) demonstrate normoxic animals at five and eight weeks while (e) and (g) demonstrate vascular thickening and remodeling of the pulmonary vasculature (black arrows) in Sugen–hypoxic rats at five and eight weeks, respectively. RVSP: RV systolic pressure; SuHx: Sugen–hypoxia; RV: right ventricle; LV: left ventricle.

Article Snippet: Hemodynamic measurements were taken using an ultra-miniature Polyimide Nylon catheter capable of measuring ventricular pressure continuously (AD Instruments SPR-869NR, Millar).

Techniques: Immunohistochemical staining, Staining, Isolation

Journal: Pulmonary Circulation

Article Title: Understanding longitudinal biventricular structural and functional changes in a pulmonary hypertension Sugen–hypoxia rat model by cardiac magnetic resonance imaging

doi: 10.1177/2045894019897513

Figure Lengend Snippet: RV end-systolic volume index (RVESVI) (a), RV end-diastolic volume index (RVEDVI) (b), RV mass index (c), RV ejection fraction (RVEF) (d), ventricular mass index (VMI) (e), and Stroke volume index (SVI) (f) in normoxia ( n = 8), five week Sugen–hypoxia ( n = 4) and eight week Sugen–hypoxia ( n = 4). RV end-diastolic and end-systolic volumes and RV mass were determined by manual planimetry and indexed to body surface area. RVEF was determined by ((RVEDV – RVESV)/RVEDV) × 100%. A demonstrates progressive increase in RV end-systolic volume index during the course of Sugen–hypoxia, while B demonstrates RV dilatation at eight weeks. RV mass index (c) was significantly increased in five week and eight week Sugen–hypoxia compared to normoxic rats. RVEF (d) was preserved, however, trending toward deterioration at eight weeks. Ventricular mass index (VMI) was calculated as the ratio between RV mass to LV mass. Interventricular septum was considered as part of the LV. VMI maybe an alternative to RV/(LV + septum) measured at autopsy as discussed. Results demonstrated increased VMI at five weeks and eight weeks of Sugen–hypoxia compared to normoxic rats (e). There were no significant differences in stroke volume index (SVI) between normoxia, five week Sugen–hypoxia and eight week Sugen–hypoxia (f). Results are shown as mean ± SEM. The groups were compared by ANOVA and if there was statistical significance, a Tukey HSD test was used for post hoc. LV: left ventricle; RV: right ventricle; SuHx: Sugen–hypoxia.

Article Snippet: Hemodynamic measurements were taken using an ultra-miniature Polyimide Nylon catheter capable of measuring ventricular pressure continuously (AD Instruments SPR-869NR, Millar).

Techniques:

Journal: Pulmonary Circulation

Article Title: Understanding longitudinal biventricular structural and functional changes in a pulmonary hypertension Sugen–hypoxia rat model by cardiac magnetic resonance imaging

doi: 10.1177/2045894019897513

Figure Lengend Snippet: LV end-systolic volume index (LVESVI) (a), LV end-diastolic volume index (LVEDVI) (b), LV mass index (c), LV ejection fraction (LVEF) (d), LV eccentricity index (LVEI) in systole (e) and LV eccentricity index in diastole (f) are shown in normoxia ( n = 8), Sugen–hypoxia at five weeks ( n = 4) and Sugen–hypoxia at eight weeks ( n = 4). LV end-diastolic and end-systolic volumes and LV mass were determined by manual planimetry and indexed to body surface area. LVEF was determined by ((LVEDV – LVESV)/LVEDV) × 100%. There were no significant differences between the normoxic group and different stages of Sugen–hypoxia in LVESVI, LVEDVI, LV mass index, and LVEF. Left ventricular eccentricity index (LVEI) was defined as the ratio of the anterior-inferior and septal–posterolateral cavity dimensions at the mid-ventricular level and was measured at both systole (e) and diastole (f). Although there were no significant differences between the three groups in the LVEI in diastole, LVEI was higher in both Sugen–hypoxic groups compared to normoxia in systole. Previous human studies had demonstrated LVEI in systole to correlate with pulmonary hypertension. The groups were compared by ANOVA, and if there was statistical significance, a Tukey HSD test was used for post hoc analysis. Results are shown as mean ± SEM. **: p < 0.05. LV: left ventricle; SuHx: Sugen–hypoxia.

Article Snippet: Hemodynamic measurements were taken using an ultra-miniature Polyimide Nylon catheter capable of measuring ventricular pressure continuously (AD Instruments SPR-869NR, Millar).

Techniques:

Journal: Pulmonary Circulation

Article Title: Understanding longitudinal biventricular structural and functional changes in a pulmonary hypertension Sugen–hypoxia rat model by cardiac magnetic resonance imaging

doi: 10.1177/2045894019897513

Figure Lengend Snippet: Cardiac MR images ((a) to (c)) and light microscopy images ((d) and (e)) of short axis sections of rat hearts. (a) and (d) demonstrate a normoxic rat. (b), (c), and (e) demonstrate a Sugen–hypoxic rat. (b) and (c) demonstrates the same animal short axis at diastole (b) and systole (c). (f) demonstrates the correlation between RV hypertrophy assessed by weighing RV and LV + S at autopsy and by ventricular mass index by CMR in normoxic rats and Sugen–hypoxic rats. There was very good correlation between VMI measured by CMR vs autopsy (Spearmen r = 0.8328). However, CMR images demonstrate functional aspects of RV contraction including septal flattening and paradoxical septal motion during systole (c) due to RV pressure overload. LV: left ventricle; RV: right ventricle; CMR: cardiac magnetic resonance; VMI: ventricular mass index.

Article Snippet: Hemodynamic measurements were taken using an ultra-miniature Polyimide Nylon catheter capable of measuring ventricular pressure continuously (AD Instruments SPR-869NR, Millar).

Techniques: Light Microscopy, Functional Assay