Conditional immortalisation of cells is a powerful tool for establishing in vitro models maintaining a differentiated phenotype. We are utilising this approach to derive cell lines that maintain the characteristics of glomerulosa and fasciculata cells of the adrenal cortex. Such cell lines should provide a system in which to study aspects of adrenocortical function that are relevant to hypertension, such as the effects of the renin-angiotensin system on steroidogenesis.