Posted by Amelia_in_StPaul on June 23, 2009, at 11:03:12
In reply to Valium defeats Prozac's antidepressant effects?, posted by SLS on June 19, 2009, at 12:19:46
WOW. I wonder if this is true of Lorazepam as well. It would explain a LOT. Thanks, Scott
> According to this brief report, if accurate, either Valium interferes with the antidepressant effects of Prozac, or the neurogenesis model for the recovery from depression is wrong.
>
> Personally, it is my suspicion that the reduction in the size of the hippocampus seen in MDD is the result of the atrophy due to its disuse rather than its being a site for the induction of the disease process. If this is true, we might see a clinical response to Prozac, but with the memory impairments sometimes attendant with the use of Valium. Actually, this might be a good model for the induction of memory impairments with benzodiazepine usage.
>
> Just throwing some stuff out there.
>
>
> - Scott
>
>
> ------------------------------------------
>
>
> Biological Psychiatry
> Volume 66, Issue 1, 1 July 2009, Pages 5-8
>
> Co-Treatment with Diazepam Prevents the Effects of Fluoxetine on the Proliferation and Survival of Hippocampal Dentate Granule Cells
>
> Neuroscience Center, University of Helsinki, Helsinki, Finland
>
> Received 29 April 2008;
> revised 16 January 2009;
> accepted 16 January 2009.
> Available online 28 February 2009.
>
> Background
>
> Selective serotonin reuptake inhibitors (SSRI) often produce increased anxiety during the first weeks of treatment before the clinical antidepressant response, and these symptoms are commonly treated with benzodiazepines. Selective serotonin reuptake inhibitors increase proliferation of neuronal progenitors in rodent hippocampus after a delay of approximately 2 weeks.
> Methods
>
> We have used this delayed increase in neurogenesis, as detected with both a rapid dot-blot method and with immunostaining, as a model of the delayed clinical antidepressant effects.
> Results
>
> Whereas the SSRI fluoxetine alone significantly increased both neurogenesis and survival of newborn cells when administered for 23 weeks, co-treatment with diazepam and fluoxetine completely blocked the increase in both neurogenesis and survival. Furthermore, neurogenesis was not increased when fluoxetine and diazepam were first co-administered for 2 weeks and then fluoxetine was given alone for 2 additional weeks. Moreover, we show that daily administration is necessary for neurogenesis, because injection of fluoxetine for up to 1 week failed to increase neurogenesis, when assayed at 14 days from the first injection.
> Conclusions
>
> These results suggest that benzodiazepines might interfere with the clinical effects of fluoxetine or that increased neurogenesis is not a valid model for the delayed onset of the clinical antidepressant effects.
>
>
poster:Amelia_in_StPaul
thread:902045
URL: http://www.dr-bob.org/babble/20090620/msgs/902739.html