The giomerular mesangium is a supporting structure that includes the mesangial cells and an intercellular substance, the mesangial matrix. Mesangial cells are steilate in shape and resemble morphologically smooth muscle cells (1, 2). They contract in response to binding of angiotensin II (3, 4) and vasopressin (4). They also produce prostaglandins (PG) 1 (5) and synthesize the mesangial matrix ...

Thrombin stimulates and heparin and heparan sulfate inhibit mesangial cell proliferation. In addition, heparin has been shown to inhibit thrombin-stimulated smooth muscle cell proliferation. The anticoagulant action of heparin is mediated by antithrombin Ill. This study investigated whether heparin’s antiproliferative action is also mediated by antithrombin Ill. To this end, the effect of antit...

Glycosphingolipids (GSLs) play a role in insulin resistance and diabetes, but their role in diabetic nephropathy (DN) has received limited attention. We used 9- and 17-wk-old nondiabetic db/m and diabetic db/db mice to examine the role of GSLs in DN. Cerebrosides or monoglycosylated GSLs [hexosylceramides (HexCers); glucosyl- and galactosylceramides] and lactosylceramide (LacCers) were elevated...

To define the interplay of glomerular hypertension and hypertrophy with mesangial extracellular matrix (ECM) deposition, we examined the effects of glomerular capillary distention and mesangial cell stretching on ECM synthesis. The volume of microdissected rat glomeruli (Vg), perfused ex vivo at increasing flows, was quantified and related to the proximal intraglomerular pressure (PIP). Glomeru...

BACKGROUND Platelet-derived growth factor (PDGF) is a potent activator of mesangial cell proliferation and migration. Although phosphoinositide 3-kinase (PI3K) enzymes are important downstream targets of the PDGF receptor, the contribution made by their 3-phosphoinositide products in the reorganization of actin cytoskeleton and focal adhesions has been questioned. METHODS AND RESULTS Pharmaco...

Cytoskeleton alterations are a hallmark of mesangial cell activation during glomerulosclerosis. The aim of this study was to investigate whether mycophenolic acid (MPA) affects cytoskeletal organization and motility of human mesangial cells. Using the IP15 cell line, we found that treatment with 1 micromol/L MPA inhibited both receptor-dependent (angiotensin II) and receptor-independent (KCl) c...

In developing glomeruli, laminin alpha5 replaces laminin alpha1 in the glomerular basement membrane (GBM) at the capillary loop stage, a transition required for glomerulogenesis. To investigate domain-specific functions of laminin alpha5 during glomerulogenesis, we produced transgenic mice that express a chimeric laminin composed of laminin alpha5 domains VI through I fused to the human laminin...

OBJECTIVE K(Ca)3.1 channel participates in many important cellular functions. This study planned to investigate the potential involvement of K(Ca)3.1 channel in premature senescence, myofibroblast phenotype transition and proliferation of mesangial cells. METHODS & MATERIALS Rat mesangial cells were cultured together with TGF-β1 (2 ng/ml) and TGF-β1 (2 ng/ml) + TRAM-34 (16 nM) separately for ...

The giomerular mesangium is a supporting structure that includes the mesangial cells and an intercellular substance, the mesangial matrix. Mesangial cells are steilate in shape and resemble morphologically smooth muscle cells (1, 2). They contract in response to binding of angiotensin II (3, 4) and vasopressin (4). They also produce prostaglandins (PG) 1 (5) and synthesize the mesangial matrix ...