Ageing and the nervous system

Physiological consequences of neuronal ageing, gross changes in brain weight

GYRI and SULCI - GYRI of cortex decrease in bulk sulci widen

Ventricles - markedly increase in size

Biochemical - protein content, brain protein decreases with age

DNA content increases, glial cell proliferation

Netabolism, blood flow reduction elderly

neurotransmitters - decrease in enzymes synthesizing dopamine

altered sleep/mood/appetite, lack of motor control

Anatomical changes - swelling of neurone cells, loss of synaptic cleft, neurofibrally tangles, consist of paired helical filaments, neuretic plaques, concentrated in hippocampus, found in extracellular matrix compared of central core of amyloid protein.

pigmented subcellular organelles

found in aged brains as green, yellow, brown

granulovascular organelles

vacuoiles or holes forming within cytoplasm and dendrites of neurones

4th most common cause of death

reduces life expectancy

wide scale demyelination of neurones

progressive loss of sensory function

motor control, mucle atrophing

dementia- loss of intercellular function

can trigger neuronal death in the healthy nervous system

related to loss of cholengic neurons in the nucleas basalls