ABSTRACT
A. Measurement of Local Mediator Concentration Microdialysis has been used to assess local histamine concentrations in human skin under control conditions (3-5). However, the main results in the arena of itch research were gained by measuring the histamine release in response to exogenous mediators. A multitude of studies has been conducted to assess the histamine concentrations in response to various mediators in controls and patients (2,6-21). Studies investigating the role of neuropeptides and mast cells for itch will be dealt with in detail below. Histamine release could be assessed in parallel to the itch sensation in type 1 allergy and urticaria (17,22,23). These results mainly confirm the role of mast cell-derived histamine in these conditions.
