Abstract: Objective To compare the effects of enzyme digestion with differential attachment and enzyme digestion with
differential attachment plus 5’-bromodeoxyuridine (5-BrdU) (conventional) method for isolating sino-atrial node cells from
newborn rats for patch clamp studies. Methods The sino-atrial node tissue were removed from neonatal Wistar rats, digested
and separated into single sino-atrial node cells with the above two methods. The obtained cells were observed for morphology,
structure, beat frequency, degree of difficulty for patch clamp experiment and the success rate. The atrial cells isolated with
enzyme digestion with differential attachment served as the control cells. Results The spindle-shaped cells constituted the
greatest proportion of the cultured sino-atrial cells, and the cultured atrial cells showed mostly a triangular morphology. Both
of the sino-atrial cells separated with the two methods contained mostly spindle-shaped cells, in which spontaneous action
potential was recorded. The spindle-shaped cells isolated with enzyme digestion and differential attachment showed a greater
viability with a higher success rate in patch clamp studies. Conclusion The sino-atrial node cells can be successfully isolated
with enzyme digestion and differential attachment, which requires simple procedures and well preserves the cell viability for
better performance in patch clamp experiment.