Identifying neuronal non-L Ca2+ channels--more than stamp collecting?

The pharmacology of the majority of Ca2+ channels in the nervous system is very limited. Although attempts have been made to constrain native Ca2+ channels into the framework provided by the six pore-forming molecules cloned to date, refined biophysical analysis of Ca2+ currents, expression techniques and the use of selective toxins have helped to identify unambiguously only a limited number of Ca2+ channels. In fact, many native Ca2+ channel activities remain as 'orphans', waiting for their molecular counterparts to be defined. In this article, Janet Nooney, Régis Lambert and Anne Feltz systematically delineate the well characterized non-L Ca2+ channel activities and the missing elements in our knowledge of the Ca2+ channel family.