When Jenn Lost Her Nerve
A Closer Look at Chemical Synapses
Department of Biology
In many physiology classes the frog neuromuscular junction (NMJ) is presented as the classic example of a chemical synapse, but many synapses show properties that are different. For example, in many chemical synapses there is a protein transporter in the presynaptic membrane that is responsible for the uptake of liberated neurotransmitter from the synaptic cleft. Certain drugs can interfere with the function of these transporters and therefore can change the level of neurotransmitter in the cleft. This interrupted case study tells the story of one student who takes a prescription drug to control depression and a second student who takes amphetamines to act as a stimulant and maintain his ability to concentrate. The two drugs affect the pre-synaptic reuptake transporter for different neurotransmitters. This case was written for a one-semester animal physiology course taken by sophomore and junior science majors; it could also be used in a general biology course that covers the function of chemical synapses.
- Describe the signs and symptoms of depression and sudden cessation of anti-depressant drugs.
- Describe the processes controlling the release of neurotransmitter from the presynaptic terminal.
- Identify the role of the reuptake transporter in maintaining the concentration of neurotransmitter in the synaptic cleft and explain how a decline in the concentration of neurotransmitter in the synaptic cleft will produce down regulation of the receptors in the postsynaptic membrane.
- Explain how a decline in reuptake activity increases the concentration of neurotransmitter in the synaptic cleft and correlate depression with a low level of serotonin in the synaptic cleft.
Keywordsphysiology; chemical synapse; reuptake transporter; amphetamines; depression; sertraline; serotonin; catecholamine; dopamine
Educational LevelUndergraduate lower division, Undergraduate upper division
Type / MethodsInterrupted
Subject HeadingsBiology (General) | Medicine (General) | Physiology | Neuroscience |