The natural history of the chromaffin cell--twenty-five years on the beginning.

Aspects of the functional anatomy of the chromaffin cell since 1950 are reviewed--beginning with the identification of noradrenaline in the adrenal gland and the first descriptions of distinct adrenaline- and noradrenaline-storing cells. Reference is made to the identification of specific proteins and neuropeptides in chromaffin cells, of the storage of endogenous and exogenous amines including 5HT. The influence of corticosteroids and nerve growth factor on cell phenotypes is discussed and a plea made for the specific use of descriptive terms with due regard to historical and functional context: this relating particularly to the appropriate labelling of elements as SIF cells. The review includes reference to recent quantitative studies on the rat adrenal medulla and adrenal chromaffin cells and to the innervation of the adrenal medulla by pre- and postganglionic sympathetic neurons, by spinal afferent neurons and by sensory and motor vagal fibers.