“…As proline analogs, cis-HP and LACA are well established as agents that inhibit the secretion and deposition of triple helical procollagen from cells [4, 16, 271. However, although the primary biochemical targets of these drugs is in the collagen biosynthetic pathway, it must be emphasized that effects due to perturbation of interlinked processes cannot be entirely eliminated. Both cis-HP [18,20,21,29,42,501 and LACA [l, 8,9,18,20,29,38,421 have been used repeatedly for such inhibition, frequently with chick embryo tissue [5,17,40,49,511. The capacity of NPXP to inhibit proteoglycan synthesis is also well known [6,26,36,371.…”