Endotoxin effects on hypothalamic gene expression in swine following sequencing of porcine c-fos mRNA

Intravenous (i.v.) endotoxin causes fever and induces cortisol and vasopres sin release in prepubertal pigs. In order to investigate CNS events associa ted with these responses, the sequence of the porcine c-fos gene was determ ined. An oligonucleotide probe complementary to part of the c-fos mRNA sequ ence was then designed and used to examine the effect of i.v. lipopolysacch aride (LPS: 0.7 mu g/kg) on gene expression in the hypothalamus. An increas e in c-fos mRNA was detected in the paraventricular and supraoptic nuclei; expression was greater (P < 0.05) than in normal animals at 30 min, but not at 120, min after LPS injection. These results are consistent with an acti vational effect of LPS on neuroendocrine pathways involved in the release o f anterior and posterior pituitary hormones.