The mechanical activity of many smooth muscles is controlled by a cyclical depolarization known as slow waves (Bolton, 1971). Slow waves result through rhythmic Ca²⁺ release from intracellular Ca²⁺ stores through inositol 1,4,5-trisphosphate (IP₃) sensitive receptors and Ca²⁺-induced Ca²⁺ release. Ca²⁺ oscillations are transformed into membrane depolarizations by generation of a Ca²⁺-activated inward current. Importantly, the store Ca²⁺ oscillations that underlie slow waves are entrained across many cells over large distances (van Helden & Imtiaz, 2003). It has been shown that IP₃ receptor-mediated Ca²⁺ release is enhanced by membrane depolarization (Suzuki & Hirst, 1999; van Helden et al. 2000), and it is this positive feedback that underlies the long-range entrainment of Ca²⁺ stores. The present study examines the mechanisms underlying such store entrainment. In gap junction connected cells diffusion of Ca²⁺ or IP₃ across gap junctions have been implicated in synchronization of Ca²⁺ oscillations. In the present study we investigate Ca²⁺ store entrainment through depolarization-induced IP₃ receptor-mediated Ca²⁺ release. This mechanism is significantly different from the chemical coupling-based class of models as membrane potential has a coupling effect over distances several orders of magnitude greater than either diffusion of Ca²⁺ or IP₃ through gap junctions. Experimental observations predicate that electrically coupled cells can interact and modulate Ca²⁺ excitability and oscillations of other cells through voltage dependent enhancement of store Ca²⁺ release. We encapsulate this in a model where; 1) each local oscillator is composed of a cytosolic-store Ca²⁺ excitable system, 2) local Ca²⁺ oscillations are coupled to membrane potential, and, 3) membrane potential influences the local Ca²⁺ oscillator through a positive feedback loop. We construct a coupled cell pair according to the schema outlined above using our previously presented single cell model (Imtiaz et al. 2002). Here we use voltage-dependent IP₃ synthesis to model the positive feedback of membrane potential on cytosolic-store excitability. The effect of electrical coupling strength on synchronization of a cell pair is studied. It is shown that weak electrical coupling is sufficient to synchronize even heterogeneous cell pairs. A comparison is made between electrical and chemical coupling (through diffusion of Ca²⁺ or IP₃). It is shown that chemical coupling is not effective when cells are weakly coupled and have different intrinsic frequencies. The result of this study show that electrical coupling acting through voltage-dependent modulation of store Ca²⁺ release is able to synchronize oscillations of cells even when cells are weakly coupled (or widely separated) and/or have different intrinsic frequencies of oscillation.