Attenuating effects of prior oestradiol benzoate priming on 5-HT-mediated lordosis behavior in rats are dose-dependent.
The present study was designed to investigate the role of the 5-HT7 receptors in lordosis and compare the lordotic responses with 5-HT1A agent under the influence of different steroid-priming regimens in ovariectomized, non-receptive and receptive rats. 8-OH DPAT, a 5-HT1A agonist and 5-CT, a 5-HT7 agonist inhibited the lordosis differently in non-receptive and receptive rats, however, the response was attenuated in a dose-dependent manner following 5-CT treatment in the first two tests. Treatment with 5-HT1A antagonist, WAY 100 135 caused a protective effect which was evident in the second test only. Priming with 25 microg OB attenuated in the first test in non-receptive rats whereas the same dose repeated a similar pattern in receptive rats. The attenuation of LQ was evident in rats treated with 5-HT7 antagonist, SB 269970-A. This finding shows that WAY 100 135, a 5-HT1A antagonist has potency to attenuate inhibitory influence of 8-OH DPAT by enhancing lordosis behavior acutely in female rats with a low estrous state. Treatment with 5-CT and SB 269970-A as 5-HT7, agonist and antagonist, respectively, have mimicked 5-HT-mediated lordotic response as moderate affinity towards 5-HT1A receptors has been reported. This offers a comparable effect on lordosis as a result of the two 5-HT agents used.
Siddiqui
A
A
Department of Biological and Biomedical Sciences, Aga Khan University, Stadium Road, Karachi-74800, Pakistan. arif.siddiquiv@aku.edu
Shaharyar
S
S
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D018492:Dopamine Antagonists / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D008297:Male; D010052:Ovariectomy; D010636:Phenols / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology; D011187:Posture; D051381:Rats; D017208:Rats, Wistar; D044282:Receptor, Serotonin, 5-HT1A / Q000187:drug effects* / Q000378:metabolism; D011985:Receptors, Serotonin / Q000187:drug effects* / Q000378:metabolism; D012018:Reflex / Q000187:drug effects*; D012701:Serotonin / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D013449:Sulfonamides / Q000494:pharmacology
C522380:5-HT(7) receptor, rat; D018492:Dopamine Antagonists; D010636:Phenols; D010879:Piperazines; D011985:Receptors, Serotonin; C404922:SB 269970; D017366:Serotonin Receptor Agonists; D013449:Sulfonamides; D044282:Receptor, Serotonin, 5-HT1A; C081293:WAY 100135; C074283:estradiol 3-benzoate; D012701:Serotonin; D004958:Estradiol; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; C047087:5-carboxamidotryptamine