Fig. 4.

Floating microelectrode recordings of V_m in cat isolated SAN showing a stretch-induced shift of MDP towards less negative values resulting in (A) restoration of regular activity in a preparation with an irregular rhythm and (B) initiation of spontaneous discharge in an otherwise quiescent preparation. In both examples, tissue length was increased by ∼40% from resting, with periods of stretch indicated by the lower horizontal lines.

From Lange et al. (1966), with permission.