Dexmedetomidine Dosing in Rat Pups

P7 rat pups of equally distributed sexes were injected with 25 µg/kg of dexmedetomidine (DEX) (Dexmedetomidine hydrochloride, Sigma-Aldrich cat. SML0956) subcutaneously either once (1×) or twice (2×), (24h after the first injection), using a 0.1 mL volume. Control animals were injected with an equivalent volume of saline (sodium chloride 0.9% Braun, Mississauga, ON, Canada). Body temperature was maintained with the use of a heated blanket and gloves filled with warm water replaced every 20 min [31 (link)]. The respiratory rate of the animal was monitored by counting breaths per minute and checked every 10 min following the first injection over the subsequent 30 min, to confirm the pup’s health. Furthermore, oxygen saturation (SpO₂) was monitored every 30 min following each injection for a period of an hour to further ensure the pup’s health and reaction to the compound (Nonin Medical, Minneapolis, MN, USA).