Recruitment of quiescent (G0) cells following epidermal injury is initiated by activation of the phosphoinositol cycle.
Under normal circumstances, the rate of production of new cells by the epidermis is rather low, but injury results in a burst of mitotic activity that continues until repair is complete. It is now recognized that most cells of the germinative population are in a resting (G0) state, and "postinjury cell renewal" is the consequence of G0 cells entering the mitotic cycle. The biochemical events triggering this process, however, are unknown. Here we show that phorbol myristate acetate (PMA) is able to induce G0 mobilization in the epidermis of the nude mouse. Further, we demonstrate that amiloride (an inhibitor of the membrane Na+-H+ pump), applied topically to human skin, abolishes almost completely the regenerative response after experimental injury. We suggest that activation of the phosphoinositol cycle may initiate recruitment of G0 cells in the epidermis.
Rijzewijk
J J
JJ
Department of Dermatology, University of Nijmegen, The Netherlands.
Bauer
F W
FW
Boezeman
J B
JB
Happle
R
R
Mier
P D
PD
D000328:Adult; D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D000078404:Epidermal Cells; D004817:Epidermis / Q000378:metabolism / Q000473:pathology; D005434:Flow Cytometry; D006801:Humans; D007295:Inositol Phosphates / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D013403:Sugar Phosphates / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D007295:Inositol Phosphates; D013403:Sugar Phosphates; D000584:Amiloride; D013755:Tetradecanoylphorbol Acetate