Stage 3 - Heat & Redness

• Vasodilation

  occurs after a few hrs

  due to the opening og local capillaries = resultant increased blood flow, heat + redness of the inflamed tissue increases the metabolic rate, speed of mitosis + tissue repair
• Vasodilation Factors

  the initial dilation is maintained by prostaglandins

  these r one of the arachidonic acid derivatives formed from cell membrane phospholipids when cell damage occurs + when the kinin system is activated
• Mechanical Changes to Blood Flow

  blood flow changes also occur thru mechanical alterations initiated by injury

  normally the blood flow in the venules, in particular, is axial
• Blood Flow in a Damaged Capillary

  in a damaged capillary, fluid is lost + so the axial flow slows

  marginilisation occurs as the slower flow rate allows WBCs to move into the plasmatic zone + adhere to the vessel walls

  = reduces the lubricating effect of this layer + slows blood flow

  the walls themselves become covered w a gelatinous layer