NPY and bone
Genetic models such as Y receptor knockout and leptin knockout mice have begun to reveal some of the individual functions of the different Y receptors. The finding that some of these receptors appear to be involved in the regulation of bone formation via a hypothalamic relay, has revealed not only a previously unknown and novel function of the Y receptors, but also a novel example of the regulation of bone formation by a very potent, centrally-mediated mechanism.
The rapid increase in bone mass in adult mice following central deletion of Y2 receptor function suggests new possibilities for the prevention and anabolic treatment of osteoporosis. The Y2 receptor pathway appears to be distinct from the antiosteogenic pathway regulated by leptin, and therefore supports the Y2 regulated pathway as a novel target for anabolic bone therapy. Furthermore, the area of the arcuate nucleus where the Y2 receptors are located is accessible without the need to cross the blood brain barrier, and is therefore potentially an ideal target for drug intervention. The additional advantage of this particular sub-population of arcuate Y2 receptors is that their specific inhibition will not influence any other central functions of the Y2 receptor such as effects on seizure susceptibility, anxiety, or memory, therefore limiting the possibility of side effects associated with such a treatment for osteoporosis.
KeywordsBone Formation Bone Volume Arcuate Nucleus Knockout Model Regulate Bone Formation
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