Acetilkolineszteráz

Acetilkolineszteráz, often abbreviated as AChE, is an enzyme that plays a crucial role in the nervous system. Its primary function is to hydrolyze the neurotransmitter acetylcholine (ACh) into choline and acetic acid. This enzymatic activity is essential for terminating the signal transmission at cholinergic synapses, allowing the neuron to repolarize and prepare for subsequent stimulation.

AChE is found in various locations throughout the body. It is abundant at neuromuscular junctions, where it breaks down ACh released from motor neurons, enabling muscle relaxation. It is also present in the central nervous system, including the brain and spinal cord, where it regulates cholinergic signaling involved in learning, memory, and attention. Furthermore, AChE is found in red blood cells, though its function there is less understood and may be related to membrane stabilization or transport.

The activity of acetylcholineszteráz is vital for proper nervous system function. Inhibitors of this enzyme can significantly impact cholinergic transmission. For instance, organophosphate pesticides and certain nerve agents work by irreversibly inhibiting AChE, leading to an accumulation of acetylcholine and overstimulation of cholinergic receptors, which can be toxic. Conversely, medications that inhibit AChE are used to treat conditions like Alzheimer's disease and myasthenia gravis, where enhancing cholinergic signaling is beneficial. The precise regulation of AChE activity is therefore critical for maintaining neuronal excitability and overall physiological homeostasis.