Final answer:
The myogenic mechanism slows blood flow into a capillary bed when there is a rising arteriolar pressure, causing contraction of smooth muscle cells in the arteriole walls to stabilize flow and prevent damage.
Step-by-step explanation:
The conditions under which the myogenic mechanism will slow blood flow into a capillary bed is when there is a rising arteriolar pressure. The myogenic mechanism is a reaction to the stretching of the smooth muscle in the walls of arterioles, which occurs as blood flow changes throughout the vessel. When blood pressure increases, the myogenic response causes these cells to contract, thereby reducing the flow into the capillary bed to stabilize blood flow and maintain homeostasis. The contracting of the arteriole walls in response to high pressure works to prevent too much blood from entering capillaries and potentially damaging them.
Key factors that can further influence the capillary beds and arteriole constriction or dilation include chemical changes within the body such as levels of oxygen, carbon dioxide, hydrogen ion, and lactic acid. However, it is the rising arteriolar pressure that is directly associated with the stimulation of the myogenic mechanism to reduce blood flow.