How does heroin affect cellular communication in the brain?

The human brain operates through the communication of impulses between various aspects of the brain cells. The nerve cells of the brain are called neurons. The nerve cells have transporters, which release brain chemicals, and receptors, which receive messages from other neurons. The chemicals that are released into the open space between each neuron are called neurotransmitters. The communications between each neuron control every aspect of how our bodies work, how we think and what we feel.