U”“ary ca,cimn EICredO” (“WCr, Plso dccreascd,then was paniauy restored.af*er n *eo”dmy PTH increase. Tk rapid ~wrccdon of UC*Cr. contrasting with a pznistcndy dccreascd urinary hydmxypmline ewxcdo”, ruggere ,il* CillCi”rnbalance v/as n-equilibnsd by a” i”EreSseddietary caIci”“l abrorpdon. e conc,urion. or.4 riscdrona,c is a s&crive a”,ia,ealas,ic
CLODROAATE CONTRACTION
INHlBlTS
compound. inducing a rapid and s,mng inhibidon of bone resorption.
INTRACELLULAR
IN VASCULAR
SMOOTH
AND EXTRACELLULAR
Cat+-INDUCED
MUSCLE
Vasilis Pas*alitis and David D. Leaver
Bisphasphonalerpnve”, Sane wxp,ian probably because,bey inhibi, ,be motility and ac,ivi,y of osteocla~,~ [II. Since cellular modlily is usually a C&.dependen, .wdn-myorin imemcdon G!1 and ,hiS pmcerr is baler dcfincd
SESSION 15 - CORTICOSTEROIDS81BONE
Uncrna~my remains regarbing ,he mechanism of somt glucoconicaid effects on calcium metabolism and ,bc relative imponance of ,he various changesdemonswad. In man. the main amid effects arc reduced oskoblw acemhy,hypwpararhymidirm. calcium mal~bsorplion. faxing byprcdciuris. bypoandmgenaemioand inerepscd oneolyrir. Wilh respecl 10 bo,h hyprpanrhymidism and increasedbone resorprion, Lhereir conflicdng evidence 1s 10 whether these are primay or recondxy phenomena.These Lcmrz work in mwxn 10 pmducc osteoporoSk.
No entirely radsfacwy manilgewn, regimen hss ken cslablished. There is now limi,ed data suggssdng ,ha, calcium rupplemen,r f viwd” D sIow Ihe raw of s,emid-induced bat loos. DUa reladng IO vimmin D and i,s mclabolitcs alone arc mixed and their paendal toxicity mwl be bane in mind. Tlduides are safe. inexpensive and likely 10 be efficacious. Sin& studies of pomidmnale and calcilonin rerpeclively. have demonswaledlheir efficxy in complelcly blocking steroid-inducedbane loss bu, availability and price limit their we a, press”,. Sex honnow replaceme”, lbempy should be inEti,uwd wbre deficiency can be doeumenlcd in either SEX. and androgcns are of value in neroid-wared women. though their use is often limited by virilising sids-effects. Evidcncc is accumulrdng lha, deflwomn is indeed P bone-sparing glucwonicaid ,be use of which may greally reduce Ihe severityof scmid-induced bone Ios. In the mc~nlimc. ,he fin, line of prophylaxis agains, this po,en,i.?lly disabling Side effec, of glucwonicoid ,hcrJpy anus, remain Ihe use of Lhelowes amid dose for Ihe shoncs, possible period.