Quiz 1 Flashcards
What are the three types of receptors that dopamine activates?
D1, alpha, and beta
What effect do beta blockers have on metabolism and the liver?
Decreased glycogenolysis in response to hypoglycemia
With membrane-delimited receptors, what happens when G-proteins interact with potassium channels?
They activate channel function and with potassium, they will be postsynaptic, resulting in a slow postsynaptic inhibition.
How does innervation of the adrenal medulla work, and is it parasympathetic or sympathetic?
It is sympathetic, and the pre-ganglionic goes all the way to the adrenal medulla, and at the junction is ACh with a nicotinic receptor, and the adrenal medulla then release NE and epinephrine into the bloodstream.
What are the three things you need to maintain the characteristic of a simple partial?
- Normal awareness 2. Memory 3. Consciousness (All throughout entire seizure)
What is the process of Dopamine entering at the adrenergic junction?
Tyrosine is transported into the noradrenergic ending or varicosity by a sodium-dependent carrier. Tyrosine is converted to DOPA (Dihydroxyphenylalanine) by tyrosine hydroxylase, and dopa is converted to dopamine by aromatic amino acid decarboxylase, and transported into the vesicle by the vesicular monoamine transporter (VMAT). Physiologic release of transmitter occurs when an action potential opens voltage-sensitive calcium channels and increases intracellular calcium. Fusion of vesicles with the surface membrane results in expulsion and dopamine can enter the synaptic cleft and do one of the following three things: 1) Bind to a post-synaptic receptor (there are 5, D1-D5), 2) Bind to the D2 autoreceptor (which would shut down tyrosine hydroxylase, so dopamine cannot be made nor released, and 3) Re-enter the neuron through a dopamine transporter. Once it does so, dopamine can be metabolized by MAO, Monoamine Oxidase, which converts dopamine into DOPAC.
What is another name for cell body?
Perikaryon
What does Propranolol act on?
Beta1 and Beta2 receptor antagonist (beta blocker)
What does an NRI do?
Blocks reuptake of NE
What is the definition of a direct action of neurotransmitters?
The neurotransmitter binds to and opens ion channels, which promotes rapid responses by altering the membrane potential.
With which type of Metabotropic receptor does the G-protein subunit interact direct with the voltage-gated ion channel?
Membrane-delimited
What are the two main alpha1 antagonists and what do they do?
Prazosin and Terazosin, they help block vasoconstriction so essentially cause vasodilation and are used to treat hypertension as well as benign prostatic hypertrophy (Tamsulosin - flomax). The side effects here are also Orthostatic hypertension and nasal stuffiness.
What are the pathway effects and receptors on eccrine glands?
Sympathetic pathway increases via M receptors?
What are the main nine precipitants (causes) of seizures
• Metabolic and/or Electrolyte Imbalance (People’s blood glucose too high or too low, too low sodium, calcium, magnesium, potassium too high) • Stimulant or other pro-convulsant intoxication • Sedative or ethanol withdrawal • Sleep deprivation • Reduction or inadequate ASD treatment • Hormonal variations • Stress • Fever or systemic infection (HSV can be linked) • Concussion and/or closed head injury
What are the main causative factors for epilepsy at a middle age?
Trauma, status epilepticus
What are the two main classes of fibers/receptors of the autonomic nervous system?
Cholinergic (Muscarinic and Nicotinic) and Adrenergic
What is the issue with having to give more than one ASD to a patient?
If you’re lucky, the patient will be controlled with a single drug, but if you are not getting good control, you will have to give another drug, which will be an inhibitor or an inducer of the other drug. If the second drug is an inducer of that enzyme, then the first drug will get chewed up and its levels will go down, and same applies the other way. If drug has a broad therapuetic index, you don’t need to worry as much about their interactions.
What effect do beta blockers have on vasculature?
Increased TPR (blockade of β2 in skeletal muscle) (??Which doesn’t make sense to me?)
What are the characteristics of a complex partial seizure and how long do they usually last?
Localized onset, spreads bilaterally usually, either awareness, memory, or consciousness is lost during seizures, and they usually last 15 sec to 3 minutes.
What are the five main therapeutic uses of epinephrine?
- Bronchospasm 2. Anaphylaxis 3. Restore function in cardiac arrest 4. Treat glaucome 5. Prolong action of local anesthetics because it is a vasoconstrictor
What are the three types of partial seizures?
- Simple partial (single focus that doesn’t spread) 2. Complex partial 3. Initial onset of secondarily generalized
What are the pathway effects and receptors on skin splanchnic vessels?
Sympathetic pathway contracts via alpha receptors
How does phenylephrine work?
It serves as an agonist to alpha1 receptors and it causes vasoconstriction to sinus vessels in order to act as a decongestant. Also causes a decreased heart rate from baroreceptor reflex essentially.
What do barbiturates do?
They increase the duration of opening time of GABA channels.
What is the definition of the pupils dilating?
Mydriasis
Which tissues do alpha1 agonists act on and what do they do?
Radial muscle of iris - constriction (dilation) Genitourinary and GI sphincters - constrict Vasculature - constrict
What are some of the tissue effects that agonists have on Muscarinic receptors?
Increase stomach acid secretion Decrease heart rate via SA node Decrease contractions via ventricles, atrium, and AV node Increase GI smooth muscle contractions (except sphincters) Increase secretory gland secretions
What does botulinum toxin do?
It prevents the release of ACh. It relaxes intraocular muscles, treats muscle dystonia (spasms), removes wrinkles.
Which neurotransmitter has a greater affinity for alpha1, alpha2, beta1, and beta2 receptors, Epinephrine or NE?
Epinephrine does. Except for Beta1 receptors, they have the same affinity here.
What does Isoproterenol act on?
Beta1 and Beta2 receptor agonist
Where is Epinephrine usually found? And what converts NE to Epinephrine?
It is mainly found in adrenal medullary cells, although it is also found in some CNS neurons. It is converted from NE by PNMT, phenylethanolamine-N-methyltransferase.
Where are the cell bodies of the parasympathetic nervous system?
Craniosacral regions
What is Tyramine’s role with the sympathetic nervous system?
Tyramine is a naturally occurring monoamine compound that serves as a catecholamine releasing agent, in other words, it helps activate the sympathetic pathways. It can displace NE once Tyramine finds its way into nerve terminals. However, tyramine is found in high amounts in certain foods like cheddar cheese and pistachios and if you are taking Monoamine oxidase inhibitors, because MAO is needed in order to break this down and metabolize it.
Which drug is associated with toxic levels if taken with grapefruit juice?
Carbamezepine. Grapefruit juice inhibits CYP3A4 enzyme in liver, so when patients take drug, the liver doesn’t metabolize the drug as it normally does and you can get toxic levels of the drug.
What is the neurotransmitter, agonists, and antagonists that act on Muscarinic receptors?
Ach Agonists: Bethanechol and Pilocarpine Antagonists: Atropine and Scopalamine
What are the four classes of symptoms that classify simple partial seizures based on cortical involvement?
- Motor 2. Somatosensory 3. Autonomic 4. Psychic (“aura”)
How does a ligand-gated ion channel work? And what is another name for these types of channels?
A hormone, drug, or transmitter binds to the protein and the channel opens up. Action is immediate and brief, some are excitatory and open channels for small cations, some are inhibitory and allow Cl- influx or K+ efflux to cause hyperpolarization. Examples include glutamate (AMPA) and nicotinic ACh receptors and GABA-A. They are also called Ionotropic.
What is the definition of a heteroreceptor?
It is a receptor on an axon terminal through which neurotransmitters from other neuronal types can influence the function of the terminal, and they are almost always inhibitory.
What are the main two types of adrenergic receptors that NE and epinephrine act on?
Alpha and Beta
Where are the cell bodies of the sympathetic nervous system?
Thoracolumbar region
How do opioid receptors modulate the release of neurotransmitters?
If endorphins bind to opioid receptors, it decreases the release of GABA (because opioid receptors are found on GABA neurons), which in turn will increase release of dopamine, because the dopamine neuron relies on a GABA receptor with GABA occupied in it in order to slow down release of dopamine.
What is the process of NE entering the synaptic cleft of an adrenergic junction and when does it happen?
For this to happen, it all starts with Tyrosine again, which is converted to Dopamine and Dopamine’s same process takes place but once it enters the synaptic vesicle via VMAT, Dopamine is then converted to NE by Dopamine Beta Hydroxylase, DBH. NE can then enter the synaptic cleft and have the same three options as Dopamine does. However, instead of binding to D1-D5 post-synaptic receptors, NE binds to alpha and beta receptors. And there is no D2 pre-synaptic receptor, it is an alpha-2 receptor.
Phenytoin
Used for all Partial seizures as well as Tonic-Clonic seizures. It masculinizes (hirsuitism) and causes severe gingival hyperplasia, osteopenia, anemia, acne. This drug is special because it has zero-order kinetics at high doses. Most drugs have first-order kinetics. So with this, as you give Phenytoin to patients, it overcomes the metabolize enzymes in the liver, so with even the smallest increase in dose, you get an upshoot increase and can become highly toxic. You have to constantly monitor the levels in your patient. It’s MOA is that it blocks sustained high frequency of action potentials by blocking Na+ channels during repetitive firing.
What are the pathway effects and receptors on fat cells?
Sympathetic pathway increases lipolysis via beta3 receptors
What are the two types of Metabotropic receptors?
Membrane-delimited and Diffusible second messengers
What does methylphenidate do?
It blocks the reuptake of dopamine
What are the three main side effects of epinephrine?
- Cardiac – increased heart rate, palpitaKons, arrhythmias, anginal pain 2. Vascular – increased TPR leading to pallor and increased BP 3. Respiratory – increased TRP can lead to pulmonary edema
What is the process of glutamate at the glutamatergic junction?
Alpha-ketoglutarate is the precursor to glutamate. It enters and is converted by amino transferase to Glutamate. It then enters a storage vesicle through a vesicular glutamate transporter. When it enters the synaptic cleft, glutamate can do 1 of 4 things. 1)It can re-enter the neuron through a glutamate transporter, however MAO does not metabolize it here because glutamate is not a monoamine. 2) It can bind to a post-synaptic receptor like AMPA, or NMDA. 3) It can bind to an autoreceptor. 4) It can enter an astrocyte, be converted to glutamine by glutamine synthetase, and by converting to glutamine, it serves as a storage buffer to be taken back up and be converted back to glutamate.
What does Albuterol act on?
Beta2 agonist (for asthma)
Which tissues do alpha2 agonists act on and what do they do?
Vasculature - constriction NE terminals - decrease NE release Brainstem - decrease NE release
What are the pathway effects and receptors on bronchial smooth muscle?
Sympathetic pathway relaxes via beta2 receptors and parasympathetic contracts via M receptors
What are the two main neurotransmitters that are amino acids?
GABA (inhibitory) and Glutamate (excitatory)
What are the pathway effects and receptors on bladder wall?
Sympathetic pathway relaxes via beta2 receptors and parasympathetic pathway contracts via M receptors
What is a postictal phase?
It is a confusion, somnolence ,with or without transient focal deficit that can lasts minutes-hours. Happens with tonic-clonic activity.
What things are cholinergic agonists used to treat?
Uses include treatment of myasthenia gravis, glaucoma, Alzheimer’s disease, smoking cessation
Carbamezepine
Used for all Partial seizures as well as Tonic-Clonic seizures. Although rare, Steven-Johnsons Syndrome is a side effect. This drug may also activate spike-wave seizures. It is also associated with toxic levels when patients drink grapefruit juice. It is a great drug for epilepsy but the potential for a drug-to-drug interaction is high. It’s MOA is it blocks Na+ channels to inhibit repetitive firing from neurons.
What does Prazosin and Terazosin do?
They are alpha1 blocker/antagonisst so they help treat hypertension.
Why administer epinephrine with caution if a patient is diabetic?
It can alter sugar balance in these individuals and it would increase gluconeogenesis and glycogenolysis via alpha and beta 2 receptors
Are parasympathetic pre-ganglionic axons short or long?
They are long, they extend to ganglia near effector organs, so the post-ganglionic are short. These are all coming out of the craniosacaral region.
What is the definition of epileptogenesis?
A sequence of events that converts a normal neuronal network into a hyperexcitable network.
Which two types of voltage-gated ion channels are the targets of Membrane-delimited signaling?
Calcium channels and potassium channels
What type of receptor does ACh act on for post-ganglionic parasympathetic fibers?
Acts on muscarinic receptors in most effector tissues.
What are the common dose-related ASD adverse effects?
Dizziness, fatigue, ataxia, diplopia, irritability, word-finding difficulty, weight loss, weight gain.
What are the characteristics of secondary generalized seizures?
They begin as simple or complex partial seizures, and when it continues to spread, it becomes generalized. Has tonic (stiffening) and clonic (jerking) phases once it becomes generalized. And all of this is finishes with a postictal phase.
What are the five “other” neurotransmitters mentioned in class?
- Histamine 2. Endorphins 3. Neuropeptides 4. Endocannabinoids 5. Nitric Oxide
What are the pathway effects and receptors on the penis?
Sympathetic pathway ejaculates via alpha receptors and parasympathetic pathway helps form erection via M receptors
What is the double-edged sword aspect of NE?
-Because NE doesn’t have much effect on Beta-2, we don’t get much dilation to compensate and we are already getting vasoconstriction so it is a double-edged sword, and when blood pressure increases, the baroreceptors will kick in and the heart rate will slow down to compensate.
What is Sarin and what does it do to the body?
Sarin is nerve gas, an acetylcholinesterase inhibitor, so it allows ACh to accumulate at the cleft and interact with cholinergic receptors to cause too much stimulation. You get a very slow heart rate, diarrhea, cramping, gland secretions, twitching, suffocation, blurred vision, sweating. Soldiers carry around Atropine as a nerve gas antidote, which will block muscarinic receptors to stop all these side effects. Atropine was originally derived from this plant on the left. And blocking these receptors would cause pupils to dilate I think.
What is the process of Serotonin entering at the synaptic cleft?
Tryptophan enters the neuron, is then converted by Tryptophan Hydroxylase to 5-HTP, and 5-HTP is then converted by AAD to 5-HT (Serotonin). 5-HT then enters the synaptic vesicle via VMAT, and eventually makes its way to the synaptic cleft where it can do the usual 3 things, bind to post-synaptic receptor, bind to autoreceptor (5-HT 1A and 1B), or re-enter through a Serotonin Transporter. And because Serotonin is a monoamine, it can also be metabolized by MAO.
What effect do beta blockers have on the kidney?
Decreased renin (which would raise BP) release
How do beta blockers work to treat hypertension?
By slowing down the heart rate. They are used by athletes and banned by most sports.
At what ages is epilepsy most prevalent?
Very young and very old
What are the pathway effects and receptors on Apocrine glands?
Sympathetic pathway increases via alpha receptors
What ratio of patients with epilepsy remain refractory to all pharmacological treatments for seizure symptoms?
1/3 of patients
What does cocaine do?
It blocks the reuptake of dopamine