This study investigates how the body's response to stress affects wound healing, especially as people age. Wound healing is the process where the skin repairs itself after injury. In younger, healthy individuals, this process usually happens smoothly. However, the study aims to understand why healing slows down in older adults and if a specific stress response mechanism is involved.

Participants will undergo procedures to create small wounds under controlled conditions to observe the healing process. The study will look for any defects in the stress response that might affect healing as people get older. Complex medical terms like 'acute wound healing' refer to the body's immediate response to skin injury.

• Who can participate: Participants must be either between 20-28 years old or at least 65 years old and in good general health. Individuals with diabetes, abnormal scarring, immunosuppression, skin infections, allergies to xylocaine, bleeding disorders, or those taking anticoagulants are excluded.
• Study details: Participants will have small wounds created under controlled conditions to study how their skin heals. The study will examine the stress response related to aging. A placebo is not used in this study.