The hormone that does the opposite of calcitonin is
The Thyroid Gland and its Hormones Calcitonin. Calcitonin is produced by the C cells of the thyroid gland and is released when levels of calcium in the blood are increased. Its role is to decrease the amount of calcium in the blood. It has the opposite action to parathyroid hormone, which increases the amount of calcium in the blood when levels fall.hen calcium levels are high, more calcitonin is released from the gland. When calcium levels fall, the release of calcitonin also falls. Some other hormones play a role in the regulation of calcitonin. Somatostatin is a hormone which reduces the release of calcitonin, and gastrin promotes the release of calcitonin.