|
Copyright © 1999 by Institute of Pharmacology Polish Academy of Sciences |
Pol. J. Pharmacol., 1999, 51, 405-413 ISSN 1230-6002 |
|
Some pharmacological properties of new analogs of MP 3022, the 5-HT1A receptor antagonist.
E. CHOJNACKA-WÓJCIK, A. KŁODZIŃSKA, E. TATARCZYŃSKA, M.H. PALUCHOWSKA. Pol. J. Pharmacol., 1999, 51, 405-413. Two new analogs of full 5-HT1A receptor antagonist 4-[3-(1-benzotriazolyl)propyl]-1-(2-methoxyphenyl)piperazine (MP 3022; 1) containing di- (5) or tetramethylene- (6) spacer were synthesized. In the radioligand binding studies, compounds 5 and 6 showed high 5-HT1A (Ki = 14.7 nM and 11.8 nM, respectively) and low 5-HT2 receptor affinity (Ki = 2696 nM and 389.2 nM, respectively). In behavioral studies both compounds behaved like postsynaptic 5-HT1A receptor antagonists as they reduced lower lip retraction and behavioral syndrome induced by 8-OH-DPAT (5-HT1A receptor agonist) in rats, but 6 was more effective in these tests. Derivative 5 did not affect body temperature in mice, whereas 6 decreased it. Furthermore, 5 did not change hypothermia induced by 8-OH-DPAT, and 6-induced lowering of body temperature in mice was not antagonized by (S)-WAY 100135 (5-HT1A antagonist), so in that model 5 and 6 did not behave as antagonist or agonist, respectively, at presynaptic 5-HT1A receptors. Compound 6 was studied in behavioral tests used to predict a potential anxiolytic (conflict drinking test in rats) and antidepressant (forced swimming test in rats) activity. Diazepam and imipramine were used as reference drugs. Compound 6 significantly increased the number of shocks accepted in water-deprived rats in conflict drinking test and shorthened the immobility time in forced swimming test in rats. The above findings indicate that new 5-HT1A postsynaptic antagonist 6 behaves like anxiolytic and antidepressant, but mechanisms of these properties of 6 remain unknown. Key words: MP 3022 analogs, 5-HT1A antagonists, structure-activity relationship, drinking conflict test, forced swimming test, rat |
| Back to: Top | PJP - Home Page | |