Neurotransmitters

Acetylcholine

________ was the first neurotransmitter discovered.

nervous systems

All ________ operate with combined excitatory and inhibitory neurotransmitters.

influence

Short- acting- ________ other cells by diffusion.

sexual dysfunction

Drugs for male ________ enhance erections by increasing or mimicking action of NO on smooth muscle.

response of postsynaptic

Often called neuromodulators- can alter ________ neuron to other neurotransmitters.

Response of postsynaptic cell

________ depends on receptor type.

Often called neuromodulators

can alter response of postsynaptic neuron to other neurotransmitters

Example

Opiate peptides

Short-acting

influence other cells by diffusion

Transferred sample of saline solution from first to second heart

rate also slowed

Ionotropic receptors

ligand-gated ion channels open in response to neurotransmitter

Metabotropic receptors

G-protein coupled receptors (GPCRs) initiate changes in postsynaptic cell

Acetylcholine

One of most widespread neurotransmitters

Released at neuromuscular junctions

Excitatory in brain and skeletal muscles but inhibitory in cardiac muscles

Biogenic amines

Widespread physiological effects and psychoactive

Abnormally high or low levels associated with a variety of mental illnesses (schizophrenia, depression)

Amino acids

Glutamate most widespread excitatory neurotransmitter

GABA (gamma aminobutyric acid) most common inhibitory neurotransmitter

Neuropeptides

Often called neuromodulators – can alter response of postsynaptic neuron to other neurotransmitters

Example: Opiate peptides

Gaseous neurotransmitters

Nitric oxide, NO

Carbon monoxide, CO

Not sequestered into vesicles

Produced locally as required

Short-acting – influence other cells by diffusion

Drugs for male sexual dysfunction enhance erections by increasing or mimicking action of NO on smooth muscle

Function of CO uncertain