Labchart 8.0 pro

Analysis of AUC was performed using LabChart 8.0 Pro with the dose–response module (ADInstruments). For each strip, the last 30 min of contractions immediately prior to commencing treatments was used as the baseline (100%). Effects of treatments were normalized against the baseline and data expressed as percent (%) of baseline contractility. Dose–response curves for AUC were generated using the non-linear regression model of GraphPad Prism 8.0 (GraphPad Software Inc., San Diego, CA, USA) and fitted through the (log inhibitor vs normalized response-variable slope) equation, Y = 100/(1 + 10^((Log IC₅₀-X)*HillSlope)). The concentration of each drug required to inhibit ex vivo myometrial contractility by 50% (IC₅₀) was determined as being a 50% reduction in total AUC relative to the contraction baseline. An ordinary one-way ANOVA followed by Dunnett’s multiple comparisons test was used to determine significant differences between the baseline and mean AUC of each dose used in the dose–response curve. A probability (P) value of < 0.05 was considered statistically significant.

Cardiovascular data were collected continuously at a sampling rate of 20,000 Hz, aside from ECG which was collected at 1,000 Hz, using LabChart (LabChart 8.0 Pro, ADInstruments, Colorado Springs, CO, USA). Screening measures, changes in body mass, and changes in plasma volume between conditions were compared using unpaired, two‐tailed t tests. Biochemical data and resting cardiovascular measures were compared using two‐way ANOVAs (age group × condition). Cardiovascular measures collected throughout the final minute of HG, PEI, and CPT were compared to their respective baseline. BP responses during the final minute of HG, PEI, and CPT were compared using two‐way ANOVAs (age group x condition). Tukey multiple comparison testing was employed in all post hoc analyses. Finally, systolic BP responses between conditions (WD minus CON) were compared between age groups using unpaired, two‐tailed t tests. All data were analyzed using GraphPad Prism 8.3 (GraphPad Software Inc., La Jolla, CA) and significance was set a priori at p < .05. All data are presented as means ± SD.