Posted by Cindy W on March 13, 2000, at 9:18:31
In reply to Re: For Cam, re: Effexor effects?, posted by Cam W. on March 13, 2000, at 7:27:23
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> Cindy - Sorry. When you block reuptake of the neurotransmitters in the synaptic cleft (gap between neurons) this leaves more neurotransmitter (NT) in the cleft, as it is not taken up by the neuron it came from. The reuptake pump is one of nature's ways of conserving neurotransmitters. If most of the NT is recycled, the body doesn't have to make more. By blocking the reuptake pump it is essentially like releasing (or leaving) more NT into the cleft and also forcing the body to make more NTs (NTs = serotonin, norepinephrine, dopamine and others). Since we are lacking serotonin and possibly norepineprine in depression, we want the body to make more.
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> That said, at lower doses Effexor increases serotonin in the synaptic cleft. At moderate doses it increases serotonin and norepinephrine and at high doses (not really used clinically) it increases serotonin, norepinephrine and dopamine in the synaptic cleft. In depression scientists have noticed a decrease in the breakdown products (metabolites) of serotonin in the cerebral spinal fluis (CSF). This CSF bathes the brain, so concentrations of metabolites in it reflects the amount of neurotransmitter in the brain. Norepinephrine seems not to be decreased, but when you block it's reuptake you seem to normalize the flow of norepinephrine between nerve cells that contain it (esp. in the locus cereuleus - major site of norepinephrine transmission in the body). I know this is a lot more than you asked for, but I hope this is a little clearer. - Cam W.Cam, thank you for explaining how this works. Do you have any comments on the article Medscape posted (http://psychiatry.medscape.com/18571.rhtml) about changes in neurons from high dosage SSRI's? Hope I'm not eventually left with no serotonergic sensitive neurons, or my body making no more serotonin!
poster:Cindy W
thread:26647
URL: http://www.dr-bob.org/babble/20000312/msgs/26850.html