Interleukin-1beta as a mechanism for stress-induced startle suppression in females

Startle measures were taken 2 h following a systemic injection of interleukin-1beta (IL-1beta) (3 microg/kg) to intact or ovariectomy (OVX) female rats. Changes in startle responsivity (reduced startle magnitude) were evident in intact IL-1beta-treated rats, despite no significant effects on startle sensitivity (number of elicited startles). No significant changes in startle sensitivity or responsivity were evident in IL-1beta-treated OVX rats. These results are discussed as a possible mechanism for stress-induced suppression of startle responsivity seen in intact female rats.