Angiotensin II causes cellular proliferation in infantile haemangioma via angiotensin II receptor 2 activation.

Aims: To investigate the effect of the angiotensin peptides and their agonists and antagonists on cellular proliferation in proliferating infantile haemangioma (IH) in vitro explants.

Methods: Proliferating IH samples from six patients were cultured in vitro in the presence of angiotensin I (ATI) alone, or AT1 and the ACE inhibitor, ramipril, or ATII alone, or ATII with the ATII receptor 1 (ATIIR1) blocker, losartan, or ATII with the ATIIR2 blocker, PD123319, or the ATIIR2 agonist, CGP42112. After 6 days in culture, the IH tissue pieces were harvested, formalin-fixed and paraffin-embedded.