Key Points
- To determine whether sympathetic vasodilator innervation exists in canine skin and to characterize the vasomotor responses of cutaneous vessels to autonomic neurotransmitters.
- Examined sympathetic vasomotor responses in the cutaneous vascular beds of the hind limbs and ears of dogs.
- Tested the vascular responses of cutaneous vessels to administrations of noradrenaline, adrenaline across various concentrations, and acetylcholine.
- Found no evidence of sympathetic vasodilator innervation supplying the skin of either the hind limbs or the ear.
- Observed pronounced vasoconstrictor action from noradrenaline and exclusively vasoconstrictor action from adrenaline even at low concentrations.
- Recorded marked vasodilator action following acetylcholine administration, indicating it remains a candidate transmitter for cutaneous vasodilator nerve endings.
Structured PICO
PPopulationDogs (skin of the hind limbs or the ear)
IInterventionNor-adrenaline, adrenaline, and acetylcholine
OOutcomeVasomotor response (vasoconstriction or vasodilation) of cutaneous vesselssurrogate
This preclinical study demonstrates that nor-adrenaline and adrenaline act as vasoconstrictors in dog cutaneous vessels, while acetylcholine acts as a vasodilator, with no evidence of sympathetic vasodilator innervation.