Catecholamine‐induced apoptosis in striatal neurons from 2 weeks old mice using a newly developed culture technique

[Background] Both dopaminergic receptor (DR) and beta‐adrenergic receptor (bAR) stimulation can produce cAMP, however, the induction of apoptosis by stimulating such receptors has not been compared, in particular, in adult striatal neurons, simply because the primary culture of such neurons has not been established. [Method] We tried to establish the method of primary culture of striatal neurons from 2 wk old mouse, and compared cAMP accumulation and induction of apoptosis by stimulating DR and bAR. [Result] Primary culture of striatal neurons from 2 wk old mouse was established for the first time. bAR stimulation with isoproterenol increased cAMP accumulation to a greater degree than DR stimulation with dopamine (bAR:121.4 + 16.0 fmol/well, DR:51.7 + 3.6 fmol/well, p<0.01, n=4) while the induction of apoptosis was much greater with DR stimulation. (bAR:17.6 + 2.3%, DR:40.85 + 2.8%, p<0.01, n=4) Further, Akt activation was much greater with bAR stimulation. (bAR:185.7 + 19.6%, DR:91.18 + 2.2%, p<0.01, n=6) [Conclusion] The role of catecholamine differs between bAR and DR even though both increased cAMP production in striatal neurons. Dopamine stimulation induced cellular apoptosis while isoproterenol did not, presumably due to cytoprotective effect of bAR through Akt activation.