TRPV1 and Alzheimer disease: Apart from low PH, aggravation of itch by warming temperatures is attributed by thermal sensor TRPV1 being sensitized by inflammatory factors in pathological condition in skin dermatitis, which possibly lowers the heat threshold to warmth sensation (120, 121) and increases the sensitivity to endogenous ligands in TRPV1 activation (122), to provoke itch in AD under environmental temperature changes.