Cerebral Blood Flow Essay

Cerebral blood flow (CBF) is the movement of blood through the network of blood vessels supplying the brain. The typical rate of blood flow in an adult is 750 millilitres per minute (AnaesthesiaUK, 2007). The arteries deliver oxygenated blood and other nutrients to the brain to ensure proper function. Studying blood flow is important for several reasons; the primary reason being the tight coupling between brain function and blood flow. This means that the brain is extremely vulnerable to reductions in blood flow beyond a certain level. When deficits occur to the CBF, cerebrovascular problems can occur such as strokes. Strokes occur when there is a lack of blood flow to the brain resulting in cell death. The result of a stroke causes part of the brain to no longer function as it should.

The neurons in the brain are more sensitive to oxygen deprivation than other types of cells. Brain tissue deprived of oxygen and glucose, caused from compromised blood flow, is likely to sustain long-lasting damage. Brief blood loss can cause cellular changes which can lead to cell death (Goldberg & Choi, 1993). Prolonged loss of blood flow leads to the deterioration of the cells, or in some cases death. Astrocytes play a huge role in neuronal survival when damage occurs in the brain (Drukarch, Schepens, Stoof, Langeveld, & Van Muiswinkel, 1998). Astrocytes are

Its role is to induce relaxation, sleep and decrease brain activity. When GABA levels are low the neurons become overexcited resulting in unwarranted muscle contraction, creating a sense of agitation and anxiety (Olsen & DeLorey, 1999). Glutamate is the excitatory neurotransmitter, 80% of neurons in the brain release only glutamate (Meldrum, 2000). Its main role is to stimulate brain cells to pay attention and process information. High levels of glutamate receptors have previously been correlated with superior abilities in learning and memory (Riedel, Platt & Micheau,