Coda non invasive system

Blood pressure was measured in vivo using the CODA non-invasive system (Kent Scientific, Torrington, CT). This system uses in vivo volume-pressure recording through a tail cuff to obtain the measurement of systolic blood pressure (SBP) and diastolic blood pressure (DBP). The machine can take measurement in up to 8 mice at one time.^{19 (link),20 (link)} CODA has been validated with telemetry with 99% correlation.^{21 (link)} Mice were acclimated to restrainers, and then blood pressure was monitored over a period of 10 cycles and averaged to obtain summary blood pressure measurements. Each cycle consisted of inflation and deflation of the tail cuff to achieve a minimal blood volume necessary to measure blood pressure (default setting: 15μL). Further default settings included a deflation period of 15 seconds and 5 seconds between each cycle.

Blood pressure was determined in vivo using CODA non-invasive system (Kent Scientific, Torrington, CT) before pregnancy and 1 and 2 months postpartum. In vivo volume-pressure recording (VPR) via tail following previously validated methods^{22 (link)} obtains measurement of systolic and diastolic blood pressure with ability to detect changes in tail blood volume in up to eight mice simultaneously.²³ To obtain these measures, mice were first acclimated to restraints followed by 20 cycles of blood pressure measurement. Systolic blood pressure (SBP) was determined from the point in which tail blood volume increases. Diastolic blood pressure (DBP) was indicated by the occlusion cuff pressure at which the blood flow into the tail equilibrates. CODA has been validated with telemetry with 99% correlation.^{24 (link)}