Published online by Cambridge University Press: 22 August 2009
Introduction
Interest in programmed cell death (PCD) emerged over a century ago (reviewed in Clarke and Clarke, 1996), and such naturally occurring cell death in the developing nervous system has been extensively documented (Oppenheim, 1991 for review). More recently, the concept of PCD has been the subject of some controversy mainly due to the overwhelming interest in one of its forms, apoptosis (Sloviter, 2002). For the purpose of this chapter, PCD is defined simply as a sequence of events based on cellular metabolism that leads to cell destruction (Lockshin and Zakeri, 2001; Guimarães and Linden, 2004), without commitment to particular morphological types.
Programmed cell death has been identified using a variety of techniques, though each of them is prone to errors when estimating the magnitude of cell loss. Estimating the size of the population based on counts of axons in developing nerves or tracts may be confounded by the simultaneous occurrence of both cell death and axonal ingrowth, and by the transient contaminating presence of other axonal populations. Estimates based on cell counts may be influenced by the continuous migration of differentiating cells into spatially delimited cell populations, as well as by the inclusion of other types of cells that are not so readily discriminable at earlier developmental stages. And while great progress has been made in understanding the molecular mechanisms of apoptosis in the last decade, multiple alternative pathways of PCD add a further degree of complexity in understanding developmental cell death and estimating its magnitude.
To save this book to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.