This study aims to establish a novel approach assisting the rational development of analgesic and anti-inflammatory drugs. In a first step we will test in healthy human volunteers whether proteins mediating inflammation and pain can be detected in an experimentally induced inflammatory skin lesion. Fluids that will be used to detect such proteins will be collected from the inflamed skin site via small porous catheters. We wish to establish the expression pattern of different proteins and correlate it with various tests assessing pain.

Inclusion Criteria:1. Age between 21-60. 2. Skin type II or III according to the classification of Fitzpatrick (II: fair skin, always burns, sometimes tans, III: medium skin, sometimes burns, always tans).
 Exclusion Criteria:1. History of a significant systemic disease, a dermatological disease, bleeding disorder, or chronic pain.

2. Consumption of analgesic drugs. 3. Hypersensitivity to sunlight.