title: Mixed lubrication after rewetting of blotted pleural mesothelium.
abstract: Coefficient of kinetic friction (μ) of pleural mesothelium blotted with filter paper, and rewetted with Ringer solution markedly increases; this increase is removed if a sufficient amount of sialomucin or hyaluronan is added to Ringer (Bodega et al., 2012. Respiratory Physiology and Neurobiology 180, 34-39). In this research we found that μ of pleural mesothelium blotted, rewetted, and sliding at physiological velocities and loads, decreased with increase of velocity, mainly at low velocities. Despite this decrease, μ at highest velocity was still double that before blotting. With small concentration of sialomucin or hyaluronan μ was markedly smaller at each velocity, decreased less with increase of velocity, and at highest velocity approached preblotting value. These findings indicate a regime of mixed lubrication in post-blotting Ringer, at variance with boundary lubrication occurring before blotting or postblotting with sufficient macromolecule addition. Greater roughness of mesothelial surface, caused by blotting, likely induces zones of elastohydrodynamic lubrication, which increase with velocity, while contact area decreases.
authors.affiliation: Dipartimento di Fisiologia Umana, Università degli studi di Milano, Milan, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Bodega
authors.forename: Chiara
authors.initials: C
authors.lastname: Sironi
authors.forename: Cristina
authors.initials: C
authors.lastname: Porta
authors.forename: Matteo
authors.initials: M
authors.lastname: Pecchiari
authors.forename: Luciano
authors.initials: L
authors.lastname: Zocchi
authors.forename: Emilio
authors.initials: E
authors.lastname: Agostoni
mesh_terms: D000818:Animals; D004848:Epithelium / Q000502:physiology*; D017276:Friction; D006820:Hyaluronic Acid / Q000008:administration & dosage; D007700:Kinetics; D008153:Lubrication / Q000379:methods*; D010994:Pleura / Q000033:anatomy & histology* / Q000503:physiopathology; D011817:Rabbits; D052116:Sialomucins / Q000008:administration & dosage; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D052116:Sialomucins; D006820:Hyaluronic Acid