title: The effect of stepwise expansion on the mitotic activity and vascularity of subdermal tissue and induced capsule in the rat.
abstract: This study proposes that the mitotic activity and morphology of a subdermal induced capsule in response to a tissue expander can be regulated by the application of stepwise pressure increases in the expander. Tissue expanders were introduced into the fascial plane beneath the panniculus muscle of the rat and expanded in a stepwise fashion. Biopsies were taken at 48, 96, and 144 hours postexpansion at each increased pressure level. The developing capsule exhibited an increase in mitotic activity in its innermost layer, which reached a maximum 96 hours postexpansion. Application of constant pressure beyond 96 hours resulted in a progressive decrease in mitotic activity of the capsule. These observations suggest that cell proliferation and the resulting growth and differentiation of the extracellular matrix of the capsule may be controlled by appropriate pressure changes in the expander.
authors.affiliation: Louisiana State University Medical Center, Shreveport 71130.
authors.forename: D
authors.initials: D
authors.lastname: Lew
authors.forename: J W
authors.initials: JW
authors.lastname: Fuseler
mesh_terms: D000818:Animals; D003238:Connective Tissue / Q000098:blood supply*; D003239:Connective Tissue Cells; D004847:Epithelial Cells; D004848:Epithelium / Q000098:blood supply; D005109:Extracellular Matrix; D005205:Fascia / Q000098:blood supply / Q000166:cytology; D005260:Female; D008938:Mitosis; D008940:Mitotic Index; D011312:Pressure; D051381:Rats; D011919:Rats, Inbred Strains; D012867:Skin / Q000098:blood supply / Q000166:cytology; D015626:Tissue Expansion