Normal physiology

These methods have allowed studies of fluid exchange under normal and pathological states revealing unique information about undisturbed interstitial fluid. This method has been extended to other several (e.g. dental pulp), and used e.g. to study the effect of the extracellular matrix on distribution of extracellular proteins in the interstitial fluid (exclusion).

Similarly, a long-lasting research theme in the group has been the “active role” of the loose connective tissues and the role of interstitial fluid pressure (Pif) in normal control, acute inflammation and burn injuries (see below). The α2β1-integrin is central in mediating tension from the connective tissues cells to the fibre networks, keeping the tissues in a compacted state. Several mediators can release this tension via the α2β1-integrin, and a series of chemokines (e.g. PDGF-BB) can attenuate an already reduced Pif, via the αV β3-integrin. This mechanism is active also in inflammation and tumours (see below).

Capillary filtration in the glomerulus filtration barrier (mechanisms of proteinuria) and regulation of glomerular filtration rate and are the basis for the development of renal imaging techniques. The studies include lymph drainage from the kidney and have demonstrated that there are no functional lymph vessels in the renal medulla and proposed alternative mechanisms for removal of interstitial plasma proteins.

Normal regulation of blood flow and transcapillary fluid balance in oral tissues has been focused and we have shown a novel role of the lymphatic system in oral tissues.

Dynamic Contrast Enhanced MRI (DCE-MRI) is being developed for quantitative studies of transcapillary exchange parameters in skin and skeletal muscle of genetically modified mice using the 7T MRI at the Molecular Imaging Centre (MIC) in Bergen.