Posted by mtdewcmu on December 17, 2009, at 21:04:49
In reply to What neurotransmitters am I hitting?, posted by Phidippus on December 17, 2009, at 15:40:15
> I'm just trying to figure out what my medication regimen is doing to my neurotransmitters. I take:
>
> Keppra 2000 mgKeppra is complicated, but it apparently mimics the action of GABA in some manner:
"Levetiracetam at concentrations of up to 10 µM did not demonstrate binding affinity for a variety of known receptors, such as those associated with benzodiazepines, GABA (gamma aminobutyric acid), glycine, NMDA (N-methyl-D-aspartate), re-uptake sites, and second messenger systems. Furthermore, in vitro studies have failed to find an effect of levetiracetam on neuronal voltage-gated sodium or T-type calcium currents and levetiracetam does not appear to directly facilitate GABAergic neurotransmission. However, in vitro studies have demonstrated that levetiracetam opposes the activity of negative modulators of GABA- and glycine-gated currents and partially inhibits N-type calcium currents in neuronal cells.
"A saturable and stereo selective neuronal binding site in rat brain tissue has been described for levetiracetam. Experimental data indicate that this binding site is the synaptic vesicle protein SV2A, thought to be involved in the regulation of vesicle exocytosis. Although the molecular significance of levetiracetam binding to synaptic vesicle protein SV2A is not understood, levetiracetam and related analogs showed a rank order of affinity for SV2A which correlated with the potency of their anti seizure activity in audiogenic seizure-prone mice. These findings suggest that the interaction of levetiracetam with the SV2A protein may contribute to the antiepileptic mechanism of action of the drug."
> Lithium 1200 mg
Lithium affects sodium channels, and apparently acts to decrease levels of catecholamines (dopamine, serotonin, and norepinephrine):
"Preclinical studies have shown that lithium alters sodium transport in nerve and muscle cells and effects a shift toward intraneuronal metabolism of catecholamines, but the specific biochemical mechanism of lithium action in mania is unknown."
> Prozac 40 mg
Prozac is an indirect serotonin agonist (it blocks reuptake), and it also, apparently, antagonizes some serotonin receptors.
> Seroquel XR 300 mg
Seroquel is a dopamine and serotonin antagonist at D2 and 5-HT2 receptors, respectively.
It is also an antihistamine and it blocks alpha-1 adrenergic receptors.
"The mechanism of action of SEROQUEL, as with other drugs having efficacy in the treatment of schizophrenia and bipolar disorder, is unknown. However, it has been proposed that the efficacy of SEROQUEL in schizophrenia and its mood stabilizing properties in bipolar depression and mania are mediated through a combination of dopamine type 2 (D2) and serotonin type 2 (5HT2) antagonism. Antagonism at receptors other than dopamine and 5HT2 with similar receptor affinities may explain some of the other effects of SEROQUEL.
"SEROQUEL's antagonism of histamine H1 receptors may explain the somnolence observed with this drug.
"SEROQUEL's antagonism of adrenergic α1 receptors may explain the orthostatic hypotension observed with this drug."
> Vyvanse 70 mg
Amphetamine is an indirect dopamine and norepinephrine agonist. Its effects on serotonin are minor.
I got all of the quotes from rxlist.com.
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> P
poster:mtdewcmu
thread:929735
URL: http://www.dr-bob.org/babble/neuro/20091104/msgs/929767.html