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Gap junctions between endocrine cells and FS cells
Despite FS cells lacking hormonal properties themselves, they influence the functionality of hormone-secreting endocrine cells via gap junctions. FS cells form homologous gap junctions with their adjacent counterparts, but also heterologous gap junctions with hormone-secreting endocrine cells. The gap junctions that exist between adjacent FS cells are used to propagate calcium-mediated signals throughout the pituitary to coordinate the function of excitable endocrine cells distributed throughout the gland. The endocrine-FS cell gap junctions, alongside the FS-FS gap junctions form a cell network that allows information about the physiological environment to be transferred around the pituitary to coordinate its secretory function.

Studies in various small mammals have demonstrated that the number of gap junctions is influenced by several factors, such as puberty, the menstrual cycle and lactation. In the mink, the presence of the connexon-43 protein that is functional in gap junctions, correlates to prolactin secretory demand depending on the breeding season. When prolactin secretion is highest in the spring there is the highest abundance of connexon-43 gap junctions; prolactin secretion and gap junctions are lowest in the winter. Thus demonstrating that the FS-cell network has a role in influencing prolactin secretion. This is consistent with studies in rats which found that gap junctions increased during lactation to facilitate prolactin demand. Additional studies in rats found that the number of gap junctions increases with anterior pituitary maturation, and this increase was prevented by castration in male rats which would prevent sexual maturation, and was restored to normal levels by hormone treatment. Similarly, gap junctions increase during pro-oestrus and oestrus phases of the menstrual cycle, and are decreased by fifty percent during di-oestrus. Evidently, the number of gap junctions is influenced by steroid hormone secretion from the gonads, and FS cells contribute to the pituitary-gonadal feedback loop.