Ketanserin attenuates the behavioural effects of corticosterone: implications for 5-HT2A receptor regulation

Long-lasting effects of chronic stress on DOI-induced hyperthermia in male rats

“…Chronic unpredictable stress protocols, as used in the current study, have been shown to increase basal or drugstimulated corticosterone levels in rats (Sapolsky et al 1984;Haile et al 2001). Corticosterone, in turn, increases the density of 5-HT 2A/C receptors and facilitates 5-HT 2 mediated behaviors (Kuroda et al 1992;McKittrick et al 1995;Berendesen et al 1996;Fernandes et al 1997;Gorzalka et al 2001). The corticosterone-stimulated increase in 5-HT 2 mediated behaviors can be attenuated by the administration of a 5-HT 2A receptor antagonist (Gorzalka et al 2001).…”

“…Corticosterone, in turn, increases the density of 5-HT 2A/C receptors and facilitates 5-HT 2 mediated behaviors (Kuroda et al 1992;McKittrick et al 1995;Berendesen et al 1996;Fernandes et al 1997;Gorzalka et al 2001). The corticosterone-stimulated increase in 5-HT 2 mediated behaviors can be attenuated by the administration of a 5-HT 2A receptor antagonist (Gorzalka et al 2001). It remains to be determined if administration of a 5-HT 2 receptor antagonist or a glucocorticoid receptor antagonist during the chronic stress procedure would block the stress-induced hyperthermia.…”

Conditioned taste aversion: modulation by 5-HT receptor activity and corticosterone

“…It has been shown that increases in wet dog shakes are correlated with increases in 5-HT 2A receptor activity and that chronic administration of corticosterone increases wet dog shakes by increasing 5-HT 2A receptor density (Kuroda et al, 1992). Other evidence indicates that the increase in frequency of wet dog shakes is blocked by treatment with either nefazodone or ketanserin (Gorzalka et al, 2001). This evidence, combined with the results of Experiment 1, suggests that increased 5-HT 2A receptor activity is an aversive consequence of acute lithium administration which contributes to conditioned taste aversion.…”

“…Chronic corticosterone treatment, at levels which mimic conditions of extreme stress, result in an increase in 5-HT 2A receptor density (Kuroda et al, 1992;McKittrick et al, 1995) and an increase in 5-HT 2A receptor-mediated behaviour (Gorzalka et al, 2001;Kuroda et al, 1992;Hanson et al, 1998;Gorzalka and Hanson, 1998;Berendsen et al, 1996;McKittrick et al, 1995). 5-HT 2A receptor antagonists reverse the behavioural effects of chronic corticosterone (e.g., Gorzalka et al, 2001;Hanson et al, 1998). It seems plausible that the enhancement of conditioned taste aversion by corticosterone is mediated by increased activity at 5-HT 2A receptors and/or decreased activity at 5-HT 1A receptors.…”

“…Administration of ketanserin, a 5-HT 2A receptor antagonist (Brogden and Sorkin, 1990), has been shown to attenuate the development of corticosterone-influenced behaviours (Gorzalka et al, 2001).…”