This study was performed to determine the stability of the adherens junctions associated proteins at the smooth muscle cell (SMC) plasma membrane during relaxing and activating conditions. Dog stomach, ileum, colon and trachea tissues were stored in a Ca⁺⁺-free physiological salt solution (PSS), regular PSS, or activated with 10 µM carbachol in PSS prior to rapid freezing. The tissues were subsequently sectioned and immunoreacted using antibodies for vinculin, talin, fibronectin and caveolin to determine their cellular distribution in these tissues under these conditions. In all four tissues, in all three conditions, the distribution of these four proteins remains localized to the periphery of the cell. In transverse tissue sections the adherens junctions associated proteins form a distinct punctate pattern around the periphery of the SMC at the plasma membrane. These domains alternate with the caveoli (as identified by the presence of caveolin). In longitudinal tissue sections the adherens junctions associated proteins form continuous tracks or staves while the caveoli remain punctate in this dimension as well. Caveolin is not present in the tapered ends of the SMC, where the adherens junctions associated proteins appear continuous around the periphery. Densitometry of the fluorophore distribution of these proteins shows no shift in their localization from the SMC periphery when the tissues are relaxed, or activated prior to freezing. These results suggest that under physiologically relaxing and activating conditions the adherens junctions associated proteins remain stably localized at the plasma membrane.