The wall of the gallbladder contains interwoven sheets of smooth muscle. Both cross and longitudinal profiles of smooth muscle are seen.
Cell boundaries are readily seen in this specimen.
Longitudinal Sections: The spindle-shape of cells cut through their centers is apparent. In relaxed smooth muscle, the nuclei are elongated with rounded ends. When contracted, the nuclei spiral, kink, or twist. The cytoplasm is pink, unstriated and with little detail.
Cross-Sections: individual cells vary in diameter depending on their location within the cell. Cross-sections through the middle of cells have a centrally located nuclei, usually surrounded by an unstained region.