Renin, angiotensins, and angiotensin-converting enzyme in neuroblastoma cells: evidence for intracellular formation of angiotensins.

The mechanism of formation of various peptide hormones in neuronal cells in the brain is not clear. The question of whether brain angiotensin II is formed by an extracellular mechanism as in the peripheral system or by an intracellular mechanism can be answered by using cloned cells in culture. We have screened several neuroblastoma cell lines of rat and mouse origin and found at least three cell lines that contain renin (EC 3.4.99.19), angiotensin-converting enzyme (dipeptidyl carboxypeptidase; peptidyldipeptide hydrolase, EC 3.4.15.1), and angiotensins I and II. This finding was interpreted to indicate that in these cells angiotensin formation takes place by an intracellular mechanism, in contrast to the extracellular mechanism well known to occur in plasma. This study also demonstrates the existence of viable and cloned cell lines that produce renin.