Transonic’s research product line took a leap forward with the much-discussed EndoGear release earlier this year. EndoGear’s status as the world’s first wireless, implantable telemetry system for rodent blood flow and blood pressure has headlined the product’s discussion, as it should. But as with all things that are truly innovative, novel successes can overshadow subtle ones – even if the nuances are just as valuable.

EndoGear had a long development cycle and the product officially launched at the 2022 Experimental Biology conference. We had the opportunity to present a poster showcasing some basic, but critically valuable information related to circadian rhythms. The poster data followed several successful studies conducted with 3rd party scientific partners within academia and industry.

Pharmacological maneuvers are often employed for device validation studies. Simply put, the administration of drugs with known responses are cross checked with the data collected from new technology to see if the device being validated will provide the expected results.

Using a similar approach of capturing known responses with new technology, the data presented on the poster focused on identifying known circadian fluctuations present in cardiovascular parameters, body temperature and activity. “Circadian rhythm” is an umbrella term encompassing a host of physiologic changes that are governed by the cycles of day and night. Some of these effects are readily observable (tendency to sleep). Others, like cardiac output, are inconspicuous and easily blurred by other factors. This subtlety was precisely the reason we wanted to use circadian rhythm as the “known responses” to identify in this study. Not only to show that EndoGear could detect and record these small, yet consistent fluctuations, but that they would (hopefully) conform to values described in the literature.

The study was conducted using all standard guidelines for animal housing, with special attention to room temperature and light/dark cycle (lights on/off 12 h cycle), post-op care for pain and distress management, including fluid supplementation and close monitoring of body weight, excretion, and food/water intake. Due to the sensitivity of the experiment, animal checks and necessary manipulations were conducted at the same time and in the same manner each day to minimize animal disturbance events. When thinking of sleep/awake cycles and behaviors, one must always consider that is much easier to startle/awake a sleeping animal than it is to induce sleep, hence the extra care with all activities conducted during the day, when lab staff are at work and animals should be “at rest”.

After implantation surgery, recovery was astonishingly swift and thorough with no signs of distress. Data analysis showed that all parameters recorded with EndoGear—cardiac output, mean arterial pressure, temperature, and activity—were within expected values and showing characteristic circadian fluctuations with statistically significant differences between light and dark phases.

The value of this seemingly subtle result cannot be overstated. In the research world, variable control can make the difference between an experiment that presents significant results, and one that does not—regardless of whether the researcher’s hypothesis was correct. Despite EndoGear’s full implantation, it did not disturb the animals to a measurable degree, which allowed all significant variation to be attributed to the experiment itself, i.e., “control” physiology.

This is the ultimate success that any device manufacturer seeks to achieve: that the study and the animals in it are physiologically blind to the device. Having EndoGear as the world’s first wireless, fully implantable telemetry system for flow and pressure represents the next step in chronic research possibilities. Research is about what we learn along the way. Discovery and innovation require incremental steps and small refinements. They’re about the subtle changes that gradually reshape the research landscape and that’s what we do at Transonic. Check the poster and the webinar to learn more about the EndoGear technology and this study. Contact your local representative if you would like to learn about availability of this product in your region.