<<forEachTiddler where 'tiddler.tags.contains(context.inTiddler.title)' sortBy tiddler.title ascending write '"*[["+tiddler.title+"]]\n"'>> <<tiddler AutoRefresh with: force>> 99% is in skeleton in plasma - protein-bound (47%) and complexed with PO3 and citrate (6%) ionised calcium (biologically active) is about half of total Ca and effected by albumin and acid base (low alb, low Ca) corrected Ca - total + 0.02(40-alb) controlled by PTH and calcitriol (vit D and calcitonin) impt for neuromuscular control, bone and coagulation ''Parathormone'' produced in response to decrease in ionised Ca acts on bone (osteoclast) to release Ca - rapid response acts on kidney to increase formation of active metabolite of vit D (1,25OHvitD) in kidney - so via vit D acts to inc Ca from gut (slow response) and inc renal tubular reabsorption of Ca (direct) ''Vitamin D'' regulates gut absorption of Ca so inc the amt in ECF mostly synthesised by skin from daylight, little in diet 1,25OHvitD produced by placenta and granulomatous conditions eg sarcoid ''Calcitonin'' antagonist to PTH so dec Ca