Antidepressant and hippocampal nitric oxide synthase activity <script async src="https://www.googletagmanager.com/gtag/js?id=G-1MVBX8ZRJ9"></script><script>window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);}gtag('js', new Date());gtag('config', 'G-1MVBX8ZRJ9');</script></head><body bgcolor="#ffffff" text="#000000" vlink="#293A8B" link="#8897DB" alink="#cc0000"> <font face="Verdana", "Arial", "Helvetica"><font size=-1> <blockquote> <blockquote> <h3><center> <big>Local, but not systemic, administration of serotonergic antidepressants<br> decreases hippocampal nitric oxide synthase activity </big> <br> <small>by<br> Wegener G, Volke V, Harvey BH, Rosenberg R.<br> Institute for Basic Psychiatric Research, <br>Department of Biological Psychiatry,<br> Skovagervej 2, DK-8240 Risskov, Denmark.<br> wegener@dadlnet.dk <br> <I> Brain Res</I>. 2003 Jan 3;959(1):128-34. </small><br><br> ABSTRACT</h3></center><blockquote> <big><big>N</big></big>itric oxide (NO) is an unconventional transmitter molecule in the nervous system, synthesized by nitric oxide synthase (NOS) following activation of the N-methyl-D-aspartate (NMDA) receptor. Several in vivo studies have demonstrated that NO modulates the extracellular levels of various neurotransmitters in the central nervous system, while serotonin (5-HT) re-uptake may be influenced by the NO pathway. Moreover, inhibitors of NOS exhibit antidepressant-like and anxiolytic-like properties in various animal models. Therefore, the aims of the present study were to clarify the involvement of distinct antidepressants acting on the serotonin re-uptake site in the regulation of the activity of hippocampal NOS in vitro, in vivo and ex vivo. We found that citalopram, paroxetine, imipramine and N(G)-nitro-L-arginine dose dependently decreased the hippocampal NOS activity in vitro. Moreover, local administration of citalopram, paroxetine, tianeptine, imipramine and N(G)-nitro-L-arginine significantly decreased the hippocampal NOS activity in vivo at a concentration significantly lower than in vitro. No effect on NOS activity following retrodialysis with 5-HT was observed. Acute (5 mg/kg, s.c.) and chronic (3 weeks, 20 mg/kg/24 h) systemic administration of citalopram did not influence NOS activity ex vivo. The effects on NOS represent a response to structurally dissimilar serotonergic antidepressants. However, since these data reflect effects on basal NOS activity, we believe that serotonergic antidepressants do not directly affect NOS at dosages used clinically, but the findings may reflect a secondary action of antidepressants on the glutamate NMDA receptor following their primary inhibitory action at the 5-HT transporter. <strong> </blockquote> <a href=fear-serotonin.html>Fear</A><BR> <a href=p-450.html>Metabolism</A><Br> <a href=fluoxetine.html>Fluoxetine (Prozac)</A><BR> <a href=forebrain.html>Serotonin/forebrain</a><br> <a href=tianeptine-stablon.html>Tianeptine (Stablon)</a><br> <a href=structure/index.html>Tianeptine: structure</a><br> <a href=melancholia.html>Melancholic depression</A><BR> <a href=memory-depression.html>Stress, memory and depression</A><br> <a href=depression-anxiety.html>Tianeptine for anxious depressives</a><br> <a href=electrophysiology.html>Electrophysiological effects of tianeptine</A><br> <a href=downstream.html>Tianeptine (Stablon) v paroxetine (Paxil, Seroxat)</A><BR> <a href=structure-activity.html>Structure-activity relationships/tricyclic antidepressants</A><br> <p><p><center> <br> <center> <a href=refs/index.html>Refs</a><br></b> </strong>and further reading<P><b><b> <a href=index.html>HOME</a><br> <a href="https://www.hedweb.com/confile.htm">HedWeb</a><br> <a href="https://www.nootropic.com/">Nootropics</A><BR> <a href="https://www.cocaine.wiki/">cocaine.wiki</a><br> <a href="https://www.opioids.wiki/">Future Opioids</a><br> <a href="https://www.bltc.com/">BLTC Research</a><br> <a href="https://www.mdma.net/">MDMA/Ecstasy</A><BR> <a href="https://www.superhappiness.com/">Superhapiness?</A><br> <a href="https://www.general-anaesthesia.com/">Utopian Surgery?</A><BR> <a href="https://www.abolitionist.com/">The Abolitionist Project</A><BR> <a href="https://www.hedweb.com/hedab.htm">The Hedonistic Imperative</a><br> <a href="https://www.reproductive-revolution.com/">The Reproductive Revolution</A><BR> <a href="https://www.huxley.net/">Critique of Huxley's <I>Brave New World</I></A><BR><p><strong> <a href="https://www.biopsychiatry.com/"><img src=../swan.jpg width=100 height=92 border=0 alt="The Good Drug Guide"></a><br> <a href="https://www.biopsychiatry.com/">The Good Drug Guide</a></b><br></strong></b> The Responsible Parent's Guide <br>To Healthy Mood Boosters For All The Family<br> </center></blockquote></blockquote></font>