"Postaglandian" does not appear to be a widely recognized term in scientific literature or common usage. It may be a misspelling or a niche term specific to a particular field, context, or even a fictional work. If you meant "prostaglandin," these are lipid compounds that have diverse hormone-like effects in the body, playing roles in processes such as inflammation, blood flow, and the formation of blood clots. Please provide more context for a more accurate response.