Dantrolene is a muscle relaxer that decreases the symptoms of BD by inhibiting Ca2+ release channels in the sarcoplasmic reticulum, while verapamil sequesters Ca2+ in the sarcoplasmic reticulum of muscle cells by functioning as a Ca2+ channel blocker.These drugs act by limiting the amount of Ca2+ from being released from the sarcoplasmic reticulum. When a muscle is stimulated, Ca2+ is released from the sarcoplasmic reticulum into the cytoplasm where it binds to a protein called troponin. This event allows the muscle fibers to overlap, causing a contraction. In BD, Ca2+ levels are high in the cytoplasm, which means Ca2+ can readily bind troponin, leading to muscles that are in an extended state of contraction. References


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Dysplasia is any of various types of abnormal growth or development of cells (microscopic scale) or organs (macroscopic scale), and the abnormal histology or anatomical structure(s) resulting from such growth. Dysplasias on a mainly microscopic scale include epithelial dysplasia and fibrous dysplasia of bone. Dysplasias on a mainly macroscopic scale include hip dysplasia, myelodysplastic syndrome, and multicystic dysplastic kidney. In one of the modern histopathological senses of the term, dysplasia is sometimes differentiated from other categories of tissue change including hyperplasia, metaplasia, and neoplasia, and dysplasias are thus generally not cancerous. An exception is that the myelodysplasias include a range of benign, precancerous, and cancerous forms. Various other dysplasias tend to be precancerous. The words meanings thus cover a spectrum of histopathological variations. Microscopic scale
Epithelial dysplasia
Epithelial dysplasia  consists of an expansion of immature cells (such as cells of the ectoderm),  with a corresponding decrease in the number and location of mature cells. Dysplasia is often indicative of an early neoplastic process. The term dysplasia is typically used when the cellular abnormality is restricted to the originating tissue, as in the case of an early, in-situ neoplasm.Dysplasia, in which cell maturation and differentiation are delayed, can be contrasted with metaplasia, in which cells of one mature, differentiated type are replaced by cells of another mature, differentiated type. Myelodysplastic syndrome
Myelodysplastic syndromes (MDS) are a group of cancers in which immature blood cells in the bone marrow do not mature and therefore do not become healthy blood cells.