Which system in the body is referred to as the brain's own opiate system?

The brain's own opiate system is referred to as the endorphins. Endorphins are neuropeptides produced by the body that bind to opioid receptors and are responsible for pain relief and feelings of euphoria. The name "endorphin" itself comes from "endogenous," meaning produced within the body, and "morphine," a well-known opiate used for pain relief. Endorphins play a vital role in the body's natural pain management system and contribute to overall emotional well-being.

The GABA system, while important in regulating neuronal excitability and having a calming effect, does not function as the brain's primary opiate system. The dopamine system is involved in the brain's reward pathways and is crucial for motivation, pleasure, and regulating mood, but it is distinct from the endogenous opiate mechanisms. The glutamatergic system primarily involves the neurotransmitter glutamate, which is crucial for synaptic plasticity, learning, and memory, but again, it does not have the opiate-like effects attributed to endorphins. Thus, endorphins stand out as the system that aligns with the concept of the brain's own opiate system.