This study is designed to test whether localized photodynamic therapy (PDT) treatment will
result in increased skin levels of microvesicle particle (MVP) and if the use of imipramine
will counteract PDT generated MVP release. The effects of PDT and ultraviolet B radiation
(UVB) on platelet-activating factor (PAF) and MVP production have long been part of the PI's
research experience. To test this, the investigator plans to enroll up to enroll up to 12
male subjects whom are aged 21 to age 45. These subjects will be treated with topical
5-aminolevulinic acid gel (Ameluz) to small areas of forearm followed by treatment with blue
light. The areas will then be treated with either 4% imipramine cream or cream base as
control. Four hours later, the redness of the areas will be measured using a mexameter and
MVPs measured in skin biopsies taken from PDT-treated skin.