Age-related regional variations of human skin blood flow response to histamine

The aim of the present study was to assess age-related regional variations in skin function, by measuring the cutaneous microvascular response to histamine. Histamine was topically applied to the back and forearm of young and aged volunteers, and the response was quantified utilizing laser Doppler flowmetry. Each group comprised of 14 volunteers. The cutaneous vascular response to histamine was significantly greater on the back than on the forearm of young healthy volunteers, whereas in aged ones the response over these two sites did not significantly differ. These observations indicate anatomical or functional differences between old and young skin as relates to regional variations. They may underlie some of the differences in the manifestations of disease processes in various age groups.