Blood pressure and heart rate measurements
Direct Arterial (invasive)
This method allows for direct arterial blood pressure measurement in the awake, conscious animal after surgery.
A heparined catheter is placed into the carotid artery of the anesthetized rodent and tunneled subcutaneously to extrude at the back of the neck. Anywhere from 3 to 6 hours is scheduled for recovery from surgery. The blood pressure is recorded following a 1/2 hour adaptation period after connection to the recording equipment. Measurements are acquired with Hem Software (Notocord Systems, Croissy, France) and associated pressure and ECG amplifier systems.
Non-invasive blood pressure
This method allows a measurement of non-invasive blood pressure in the awake, conscious animal.
Non-invasive blood pressures are obtained from the mice using the Blood Pressure Analysis System from Visitech Systems, Inc (Apex, NC). The pulse is detected on the tail, distal to the tail cuff, with a photoelectric sensor. The detected pulse is displayed on the computer monitor and the cuff is inflated by the system. The mice are placed on a warm platform to increase blood flow to the tail in order to improve the pulse detection. The mice are trained on the machine for 3 consecutive days, and the final values are obtained on the fourth and fifth day (unless more days are requested).
Telemetry Device implantation (mouse only)
This method allows for long term direct arterial blood pressure measurement in the awake, conscious animal after surgery.
A catheter is placed into the carotid artery of the anesthetized mice. The implantable transmitter is tunneled subcutaneously. The blood pressure is continuously or discontinuously (protocol on demand) recorded after a one week recovery period. Measurements are acquired with OpenART software (Data Science International; St Paul, MN, USA)
This technique allows to measure mice blood pressure and activity. It also allows to follow changes of these parameters for long time periods (some days to some months) without disturbing of animal. This technique allows to study acute or chronic drugs effect with continues or acute recordings.
Intraventricular catheterization to assess cardiac function (dP/dt) and , pressure-volume loops.