spaceprovided)Signaling pathways in the brain that mediate the physiological components of the response to a bacterialinfection - including fever accompanied by tachycardia and activation of the hypothalamic-pituitary adrenalaxis - are still unknown. To address this question, I plan to study the role of the dorsomedial hypothalamus(DMH) and the raphe pallidus (RP) in the changes caused by systemic administration of lipopolysaccharide(LPS), a model for the innate immune response in rats. I hypothesize that the DMH mediates increases inbody temperature, heart rate and plasma adrenocorticotropic hormone (ACTH) induced by systemicadministration of LPS in conscious rats, and that the RP specifically mediates increases in bodytemperature and heart rate induced by systemic administration of LPS in conscious rats via signaling fromthe DMH. Chemical inhibition with muscimol, a neuronal inhibitor, will be used to assess the role of theDMH and the RP in the physiological components of the response to LPS, and anatomic correlates will beexamined using combined retrograde tracing and fos immunocytochemistry.
