Markers of apoptosis in cardiovascular tissues: focus on Annexin V

In the last decade, apoptosis (or programmed cell death) has become appreci ated as an important process in the development of the cardiovascular syste m. Moreover, apoptosis contributes to the adaptation of the system to the e nvironment. We are at the beginning of understanding its relevance to cardi ovascular physiology and pathology. This understanding forms the key to imp lement apoptosis in diagnosis and therapy of cardiovascular diseases. New a venues for pharmacological intervention are expected to arise from the syne rgy of our knowledge about the molecular mechanisms of apoptosis, and how a poptosis integrates in the complex environment of the cardiovascular tissue . The latter strongly depends on techniques to measure apoptosis. Currently , we are facing a relative paucity in available techniques, covering both s pecificity and sensitivity, and furthermore allowing quantitative analysis, preferably in combination with morphology. This field, however, is rapidly evolving and is fed by the expanding knowledge about the molecular mechani sms of apoptosis. In this paper we will briefly review the available techni ques to detect and/or quantify apoptosis. These methods are based on the an alysis of cellular morphology, either by light- or electron microscopy, DNA fragmentation (TdT-mediated X-dUTP nick end labeling or in situ nick end l abeling), or cytoplasmic and membrane changes. Furthermore, the advantages and limitations of these techniques for their use in cardiovascular researc h will be outlined. In the text we will refer to available reviews and prot ocols which discuss the techniques in more detail. The main part of this ar ticle will, however, focus on a recently introduced technique, the Annexin V-based apoptosis detection assay. The principle, characteristics, pro's an d contra's of this new apoptosis detection assay will be discussed. (C) 200 0 Published by Elsevier Science B.V. All rights reserved.