Long term alterations in neuroimmune responses of female rats after neonatal exposure to lipopolysaccharide.
Male and female rats display significant gender-associated differences in their responses to an immune challenge, and gender-specific alterations in many aspects of physiology are seen after a variety of interventions during the neonatal period. It is well-established that neonatal exposure to an immune challenge can alter centrally mediated inflammatory responses in adult male rats and yet little is known about female responses after a similar challenge. We therefore asked if neonatal exposure to lipopolysaccharide (LPS) would alter febrile and hypothalamic cyclooxygenase (COX)-2 responses to an adult immune challenge in female rats. Female Sprague-Dawley rats were administered a single injection of the bacterial endotoxin LPS at postnatal day 14 and were examined as adults for febrile, COX-2 and activity changes to LPS, as well as responses to interleukin (IL)-1beta. Adult female rat responses were similar to those we have seen previously for the males in that febrile and hypothalamic COX-2 responses to adult LPS were attenuated in neonatally LPS-treated animals. Responses to adult IL-1beta were unaffected. Interestingly, females did not display the elevated basal hypothalamic COX-2 that was previously seen in males. Thus we demonstrate that, like in the males, neonatal exposure to LPS has a powerful effect on adult responses to further LPS challenge in the female rats.
Spencer
Sarah J
SJ
Department of Physiology and Biophysics, Faculty of Medicine, Hotchkiss Brain Institute, Calgary, Alta., Canada. spences@ucalgary.ca
Boissé
Lysa
L
Mouihate
Abdeslam
A
Pittman
Quentin J
QJ
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D005260:Female; D005334:Fever / Q000276:immunology*; D007031:Hypothalamus / Q000201:enzymology* / Q000276:immunology; D007375:Interleukin-1 / Q000276:immunology; D008070:Lipopolysaccharides / Q000276:immunology*; D008297:Male; D009043:Motor Activity / Q000276:immunology; D015213:Neuroimmunomodulation / Q000276:immunology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012737:Sex Factors
D007375:Interleukin-1; D008070:Lipopolysaccharides; D051546:Cyclooxygenase 2