What change occurs in the brain of Alzheimer’s patients related to cholinergic signaling?

In Alzheimer’s disease, one of the hallmark changes that occurs in the brain is a significant reduction in cholinergic signaling. Cholinergic neurons, which release the neurotransmitter acetylcholine, are particularly affected in this condition. These neurons are essential for various functions, including memory and learning processes.

As the disease progresses, there is degeneration of cholinergic neurons situated in the basal forebrain, leading to decreased levels of acetylcholine in the hippocampus and cortex, regions critical for cognitive function. This decline in cholinergic activity correlates with impairments in memory formation and retrieval, which are characteristic symptoms of Alzheimer’s.

The reduction in cholinergic signaling is so profound that it has prompted the development of therapeutic strategies aimed at enhancing cholinergic function, such as the use of acetylcholinesterase inhibitors. These medications aim to increase the availability of acetylcholine in the synaptic cleft, thus attempting to alleviate some cognitive symptoms associated with the disease.

Overall, the decrease in cholinergic signaling is a fundamental aspect of Alzheimer’s pathology, linking structural brain changes with the cognitive deficits observed in affected individuals.