Pharmacology: The bone tissue is reabsorbed by osteoclasts within the normal cellular process. Alendronic acid is a synthetic bisphosphonate located in the bone resorption zones that inhibits the activity of the osteoclasts reducing bone turnover; therefore, an increase in bone mass is obtained. Under therapy, normal bone tissue develops, and alendronate is deposited in the bone-matrix in pharmacologically inactive form. Likewise, a binding ten times higher than that of osteoclasts has been observed resulting in reduced bone turnover.
Calcium is an essential component for the function of various systems and organs of the human body (muscles, nervous system, cardiovascular, renal), among others. The bone is the biggest calcium deposit in the human body in the form of hydroxyapatite. There is an active calcium exchange among the bones and plasma fluid. As calcium is pivotal for the functioning of our organism, when there is a deficiency in plasma due to low intake or some organic alterations, the main need is met by the bone which gives its calcium to the blood stream. To maintain normal calcium levels and bone quality, it is necessary to have an adequate calcium supplementation daily.
Calcium absorption in the intestines is modified by several factors such as calcium levels in blood gastric pH, presence of fibers or phytates.
Approximately 25% of calcium taken by oral route is absorbed in the small intestine depending on the presence of the activated vitamin D.
Vitamin D is a significant factor in calcium homeostasis. 20% or 30% of the calcium absorption in the small intestine depends on the presence of this vitamin. Vitamin D3 is necessary for the formation of the normal bone tissue. The absence of this vitamin may be related due to lack of exposure to the sunlight and inadequate food intake. Vitamin D, calcitonin and parathormone regulate the calcium level in blood according to the needs of the body.