Relaxin stimulates cAMP production in MCF-7 cells upon overexpression of type V adenylyl cyclase.

Relaxin stimulates cAMP production and activation of ERK and PI3K in THP-1 cells. Relaxin also stimulates protein kinase C zeta (PKCzeta) translocation to the plasma membrane in a PI3K-dependent manner in THP-1 and MCF-7 cells. However, relaxin did not increase cAMP production in MCF-7 cells. We overexpressed different adenylyl cyclase (AC) isoforms in MCF-7 cells to examine coupling of endogenous relaxin receptors to cAMP production. Overexpression of types II and IV AC had no effect on cAMP production by relaxin. However, overexpression of type V AC, which is activated by PKCzeta, showed synergistic stimulation of cAMP by relaxin and forskolin.