Abstract P604: Equivalency Validation of a Novel Freely Moving Animal Based Telemetry System versus a Stationary Cage Bound System for Blood Pressure Recordings
Traditional rodent blood pressure (BP) monitoring required single housing, a known stressor for rodents. We developed a microprocessor based long range wireless telemetry system with large internal memory that allows rodents to live in groups, interact, exercise and be housed in large enriched environments. BP is recorded with a solid-state sensor along with core temperature and 3D axial activity within the implant. The measurement protocol is transmitted once to the programmable implant via a single room antenna mobile base station. The implant becomes an autonomous recording device until contacted again by the base station with an updated protocol. The implanted animals are thus allowed to undergo procedures, leave the room or be subject other tests while the recording is running. Data can be automatically downloaded periodically within the protocol.
In order to objectively validate this system we contracted a study with the Michigan State University INVIVO facility. 8 male SD rats of 275g were implanted with a model PTA-M TSE Stellar telemetry implant. After 8 days of recovery the animals entered a crossover study and were dosed with vehicle, 3, 10, and 100 mg/kg L-NAME or Verapamil at t=0 hrs. BP was recorded for 10s hourly for 24hrs sampled at 200Hz following drug administration. The BP responses were compared to a control group of 8 animals implanted with a similar conventional implant from a competitor. Drug responses were qualitatively the same between the groups. Mean arterial pressures (MAP) at +12hrs in the 100 mg/kg LNAME group with the TSE implant increased by 26±11 versus 26±9 mmHg in the control group. MAP in the 100 mg/kg Verapamil group at +12 hrs dropped by 31±9 versus 20±6 mm Hg in the control group. Baseline MAP was significantly elevated to 118±5 versus 92±11 in the control group with the conventional implant which may account for the blunted verapamil response.
We conclude that there are no significant differences in quantitative blood pressure responses to L-NAME or Verapamil in animals implanted with a TSE Stellar device versus a leading competing device. We also conclude that the short hourly recordings used for the TSE device produced equivalent MAP values while significantly prolonging implant battery life, thus extending possible study length.
Author Disclosures: H. Knot: A. Employment; Significant; TSE Systems Inc. G. Miller: A. Employment; Significant; TSE Systems Inc..
- © 2015 by American Heart Association, Inc.