Cerebrospinal fluid factors following subarachnoid haemorrhage accelerate collagen lattice contraction by fibroblasts

Proliferation in the intimal layer and medial necrosis are the most consistent findings in the cerebral artery following subarachnoid haemorrhage (SAH) in man. Recently, SEM studies from our laboratory have also shown marked endothelial injury as demonstrated by a profuse platelet carpet. Myofibroblasts proliferate in response to the platelet derived growth factor (PDGF), and abundant collagen is present in the vessel wall. We have employed experiments using fibroblast-populated collagen lattices to study cerebrospinal fluid (CSF) from patients with recent SAH. Isolated rat tail collagen and cultured human dermal fibroblasts are mixed together, placed in 35 mm Petri dishes, and allowed to gel. CSF samples are placed on the surface of the collagen lattice, using 0.2 ml saline for control. The collagen lattices are then incubated and daily measurements recorded. We found that CSF samples from patients with recently ruptured aneurysms significantly accelerate contraction of the collagen lattice. The factor in CSF is heat stable and has a molecular weight of less than 6000.