Long-lasting change in 5-HT2A receptor-mediated behavior in rats after a single footshock.
To investigate the long-term functional change in the 5-HT(2A) receptor after acute stress, we examined the effect of single footshock on head shake behavior induced by the 5-HT(2A) receptor agent (+/-)-2,5-dimethoxy-4-iodoamphetamine hydrochloride (DOI) in rats. Head shakes were evoked in a dose-dependent manner by 0.1-10 mg/kg of DOI, and the maximal response was attenuated by a single footshock given 24 h before. This suggests that there is a decrease in the number of functionally effective 5-HT(2A) receptors. The single footshock-induced reduction in head shakes evoked by DOI was observed immediately and 24 h after footshock, and lasted until 1 and 2 weeks after footshock. Because there were no changes in the [3H]ketanserin binding of the frontal cortex 1 week after footshock, decreases in head shakes were not due to the down-regulation of 5-HT(2A) receptors evoked by footshock.
D000662:Amphetamines / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation / Q000379:methods; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin / Q000378:metabolism*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D013312:Stress, Physiological / Q000378:metabolism*; D013995:Time
D000662:Amphetamines; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin; D017366:Serotonin Receptor Agonists; C015952:4-iodo-2,5-dimethoxyphenylisopropylamine