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Why can some neurotransmitters be both excitatory and inhibitory?
Wiki User
∙ 8y ago
Excitatory neurotransmitter usually is acetylcholine. To get inhibitory responses in a nerve cell, the arrangement of receptors is different. The study of nervous system in detail will provide you exact answer to your question.
Wiki User
∙ 13y ago
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How do psychoactive drugs affect the brain?
Psychoactive drugs can increase or decrease transmissions to post-synaptic membranes. Excitatory drugs can mimic the action of neurotransmitters or delay the breakdown of neurotransmitters. On the other hand, inhibitory drugs can hyper-polarize the post-synaptic membrane or reduce the effect of excitatory neurotransmitters.
What effect do neurotransmitters from one neuron have on the next neuron?
The two major effects are excitatory and inhibitory. For example ACh leads to the post-synaptic cell's depolarization while GABA or glycine will hyperpolarize the post-synaptic cell. But this is all a simplification. Some synapses have an effect of neuromodulators sometimes released as a co-transmitter (e.g. NPY and epinephrine from sympathetic ganglionic neurons). In some situations the cotransmitter can have a mixture of effects.
How do neurotransmitters transmit signals across the synapse?
after impulse conductionby postsynaptic neurons is initiated, neurotransmitters activity is rapidly terminated. Either one or both of two mechanisms cause this. Some neurotransmitters molecules difuseout of the synaptic cleft back into synaptic knobs
What Neurotransmitters are released at the ends of some nerve cells?
An axon
How a neuron sends internal messages?
Neurons send internal messages through the use of action potentials, which are generated through the summation of inputs from the dendrites on the other part of the neuron. These inputs are summed either temporally (over a period of time) or at the same time (instantaneous), and if they push the voltage in the zone of the axon hillock to above threshold, it results in the generation of an action potential. The action potential travels through the axon, and once it reaches the terminal bouton of the axon, it triggers calcium influx into the cell, which causes neurotransmitter release. Neurotransmitter release may either be excitatory or inhibitory depending on the neurotransmitter released; for example, in the CNS, glutamate is the major excitatory neurotransmitter, whereas GABA is the major inhibitory neurotransmitter. They bind to the post-synaptic cell, which triggers the post-synaptic cell response. Note that this is just a general overview for neural transmission; some neurons may have different mechanisms of action.
How do psychoactive drugs affect the brain?
Psychoactive drugs can increase or decrease transmissions to post-synaptic membranes. Excitatory drugs can mimic the action of neurotransmitters or delay the breakdown of neurotransmitters. On the other hand, inhibitory drugs can hyper-polarize the post-synaptic membrane or reduce the effect of excitatory neurotransmitters.
A neuron has hundreds of axonknobs impinging on it and most of the axonal knobs are firing but why does the neuron not transmit an impulse?
Probably because some portion of those synapses are inhibitory as opposed to excitatory.
What are neuro transmitters?
The nervous system is composed of many cells called neurons, these are essentially the functional units of the nervous system. ?Neurotrnasmitters are chemical messengers that are sent from one neuron to another neuron. ?So basically they are messangers communicating from one neuron to the next. ?Some neurotransmitters are excitatory which act to help activate a neuron, some neurotransmitters are inhibitory and act to reduce excitement of a neuron. ?Many many neurotransmitters will act on a neuron at a given time and the sum total will result in either an excitation or inhibition of that neuron. ?Examples of neurotransmitters include GABA, glutamate, serotonin, dopamine, acetylcholine, histamine, ?glycine, epinephrine, norepinephrine, melatonin, substance P, and many more!
What effect do neurotransmitters from one neuron have on the next neuron?
The two major effects are excitatory and inhibitory. For example ACh leads to the post-synaptic cell's depolarization while GABA or glycine will hyperpolarize the post-synaptic cell. But this is all a simplification. Some synapses have an effect of neuromodulators sometimes released as a co-transmitter (e.g. NPY and epinephrine from sympathetic ganglionic neurons). In some situations the cotransmitter can have a mixture of effects.
What are the excitatory neurotranmitters?
Glutamic acid (glutamate) is probably the most abundant excitatory transmitter. Others can be excitatory, such as acetylcholine, and some peptides. Aspartate is also excitatory. Finally, serotonin is often found to be exctitatory.
How do neurotransmitters transmit signals across the synapse?
after impulse conductionby postsynaptic neurons is initiated, neurotransmitters activity is rapidly terminated. Either one or both of two mechanisms cause this. Some neurotransmitters molecules difuseout of the synaptic cleft back into synaptic knobs
What Neurotransmitters are released at the ends of some nerve cells?
An axon
How does the end plate potential differ from a EPSP on a post synaptic cell?
End plate potential is the change in potential from neurotransmitters. It can be excitatory or inhibitory. If the action potential wants to continue, it will be excitatory and vice versa. It can be additive, if more action potentials are fired it will increase the end plate potential. An action potential is an all or none response. It will either proceed or it will not proceed depending on the terms of the threshold. It cannot be additive, because there is an absolute refractory period where no additional action potentials can be fired.
What is impact of neurotransmitters and drugs on human behavior?
Neurotransmitters are chemicals in the brain that play a key role in regulating mood, emotions, and behavior. Drugs can affect neurotransmitter levels, leading to changes in behavior. For example, drugs that increase levels of dopamine can result in feelings of pleasure and reward, while drugs that increase serotonin levels can lead to improvements in mood and decreased anxiety. However, misuse of drugs can also disrupt neurotransmitter balance and contribute to negative behavioral outcomes, such as addiction or impaired cognitive function.
How a neuron sends internal messages?
Neurons send internal messages through the use of action potentials, which are generated through the summation of inputs from the dendrites on the other part of the neuron. These inputs are summed either temporally (over a period of time) or at the same time (instantaneous), and if they push the voltage in the zone of the axon hillock to above threshold, it results in the generation of an action potential. The action potential travels through the axon, and once it reaches the terminal bouton of the axon, it triggers calcium influx into the cell, which causes neurotransmitter release. Neurotransmitter release may either be excitatory or inhibitory depending on the neurotransmitter released; for example, in the CNS, glutamate is the major excitatory neurotransmitter, whereas GABA is the major inhibitory neurotransmitter. They bind to the post-synaptic cell, which triggers the post-synaptic cell response. Note that this is just a general overview for neural transmission; some neurons may have different mechanisms of action.
What are some important neurotransmitters?
Acetylcholine, adrenaline, noradrenaline, serine GABA. dopamine etc.
How are neurotransmitters broken down in the synaptic cleft?
most neurotransmitters are not actually broken down, rather they are actively transported back into their pre release vesicles (this is called reuptake). Some neurotransmitters are broken down by a specific enzyme into non active parts i.e acetylcholine broken down by acetylcholinestarase
