Figure 2.

Serological conditions with aging and kinetic levels of nerve growth factor (NGF) and histamine in skin lesions from mice. Levels of immunoglobulin E (IgE) (a) and NGF (b) were measured in sera collected from mice kept under conventional and specific pathogen-free (SPF) conditions. Skin from a series of DS-Nh mice was collected, and histamine and NGF from skin homogenate were eluted to measure histamine (c) and NGF (d) contents using enzyme-linked immunosorbent assay (ELISA) or enzyme-based colour reaction kits. Each value represents the mean and standard deviation of 10 conventionally housed DS-Nh mice or five DS-Nh mice raised under SPF conditions.