Question

Survey some of the mechanisms by which drugs can alter presynaptic and postsynaptic processes.

Answer 1

Psychotropic drugs are the kinds of medicine that affect particular moods and behaviors, sedatives , analeptics, and hypnotics.

Psychotropic drugs affect the synaptic event. Some psychotropic drugs facilitate the consequences of a neurotransmitter, and are called agonistic. and the other type of psychotropic drugs inhibit the affect of particular neurotransmitters, and are called antagonistic.

Drugs affect synaptic transmission by increasing the quantity of neurotransmitter released into the synaptic space. Drugs like alcohol, heroin, and nicotine indirectly excite the dopamine in neurons. Resulting in increase in action potentials.As the number of action potentials increases, so does the quantity of dopamine released into the synapse.

Drugs can also alter synaptic transmission by directly affecting the postsynaptic receptors. Some drugs activate receptors, et al. block them. While THC and morphine activate specific receptors, other drugs block specific receptors. Caffeine, the mild stimulant found in coffee and soft drinks, preventing binding of neurotransmitter called adenosine to its receptor.

A third type is to affect synaptic transmission is to change the removal of neurotransmitters from the synapse. Cocaine and amphetamines work this manner. Both drugs block the dopamine transporter that removes dopamine from the synapse. The result's a rapid and protracted rise of dopamine within the synapse. Alcohol affects the brain’s neurons in different ways. It act on their membranes and ion channels, enzymes, and receptors and alter them, and it also binds on to the receptors for acetylcholine, serotonin, and GABA and therefore the NMDA receptors for glutamate. GABA allows chloride ions to enter the postsynaptic neurons resulting in reduced activity of neurons.