CROSS-FAMILIARIZATION CONDITIONED TASTE-AVERSION PROCEDURE AS A METHOD TO REVEAL STIMULUS RESEMBLANCE BETWEEN DRUGS - STUDIES ON THE 5-HT(1A) AGONIST 8-OHDPAT

In the present study a cross-familiarisation conditioned taste aversio n (CTA) paradigm was utilized to reveal stimulus resemblance between t he selective 5-HT1A agonist 8-OHDPAT and a variety of serotonergic and non-serotonergic drugs. In male mice, a 0.22 mg/kg dose of 8-OHDPAT w as used as the reference compound inducing CTA. Dose-dependent effects of pre-exposure to 24 different test drugs on the magnitude of the 8- OHDPAT-induced CTA were tested as a measure for stimulus similarity be tween these test drugs and 8-OH-DPAT (the reference compound). Pre-exp osure to 8-OH-DPAT itself, ipsapirone, buspirone, RU 24969, sertraline , d-amphetamine, LSD, metergoline and idazoxan effectively prevented t he development of CTA induced by 8-OHDPAT. Pre-exposure to apomorphine , diazepam, SCH 23390, LiCl, spiperone, DOI, spiroxatrine, umespirone, pindolol, mCPP, haloperidol, MK 212, clonidine, quipazine and also 5- MeODMT was not effective in completely abolishing the CTA produced by 8-OHDPAT. It is concluded from these results that the relatively simpl e and fast cross-familiarisation taste aversion method is a suitable p aradigm to study similarities in stimulus properties of different drug s.