He and his colleague Heather More, who is also at Simon Fraser University, took a closer look at the several neural delays involved in animal reflexes.
The two initial steps lasted for 3 min each, whereas rats continued running in the final step until they reached the point of fatigue, which was confirmed by the loss of the animal righting reflex.
The depth of anesthesia was continuously monitored by testing the animal's reflexes (e.g., pedal or eye blink reflex) during the experiment.
Moreover, the effects of cardiopulmonary afferents on peripheral sympathetic activity, especially in the kidney, may have contributed to this increase in sympathetic modulation since in diabetic animals this reflex control is blunted [ 40].
The animal's corneal reflex and toe-pinch reflex were used to monitor the depth of surgical anesthesia.
In normal animals, the crossed reflex was systematically observed, but only after an average of two attempts.
After loss of the righting reflex, animals were fixed in the supine position on a rat board.
Interestingly, in backward walking animals the TOT reflex is active, too, but leads to a behaviorally/physiologically unreasonable reaction (Schmitz and Hassfeld 1989).
To perform functional imaging studies, imaging the pupillary reflex, animals were anesthetized intraperitoneally by a cocktail containing ketamine (40 mg/kg body weight), xylazine (3 mg/kg body weight), and acepromazine (1.5 mg/kg body weight).
Anesthesia was deemed sufficient when the animal lacked a contracting reflex in response to a toe pinch.
