Imipramine treatment ameliorates corticosterone-induced alterations in the effects of 5-HT1A and 5-HT4 receptor activation in the CA1 area of rat hippocampus.
This study tested whether imipramine reverses adaptive modifications in the function of hippocampal 5-HT1A and 5-HT4 receptors induced by repetitive administration of corticosterone. Rats received corticosterone for 1 or 3 weeks or imipramine for 2 weeks. The fourth experimental group was treated with corticosterone for 3 weeks and additionally with imipramine, beginning on the eighth day of corticosterone administration. Hippocampal slices were prepared 48 h after the last drug administration. 5-HT1A and 5-HT4 receptor-mediated effects on CA1 population spike amplitude were measured. While repeated corticosterone attenuated the inhibitory effect of 5-HT1A receptor activation by 8-OH-DPAT and enhanced the excitatory effect of 5-HT4 receptor activation by zacopride, imipramine treatment of naïve rats resulted in opposite changes. In the corticosterone plus imipramine group, the effect of 8-OH-DPAT and zacopride were not different from control, indicating that corticosterone-induced adaptive changes in the reactivity of 5-HT1A and 5-HT4 receptors were reversed by imipramine treatment.
Zahorodna
Agnieszka
A
Institute of Pharmacology, Polish Academy of Sciences, Smetna 12, 31-343 Krakow, Poland.
Tokarski
Krzysztof
K
Hess
Grzegorz
G
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D000929:Antidepressive Agents, Tricyclic / Q000494:pharmacology*; D001549:Benzamides / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D003345:Corticosterone / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D004558:Electric Stimulation; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism* / Q000502:physiology; D007099:Imipramine / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D044282:Receptor, Serotonin, 5-HT1A / Q000187:drug effects*; D044422:Receptors, Serotonin, 5-HT4 / Q000187:drug effects*; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists
D000929:Antidepressive Agents, Tricyclic; D001549:Benzamides; D019086:Bridged Bicyclo Compounds, Heterocyclic; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; D044282:Receptor, Serotonin, 5-HT1A; D044422:Receptors, Serotonin, 5-HT4; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; C055971:zacopride; D007099:Imipramine; D003345:Corticosterone