TY - JOUR
T1 - Parathyroid hormone-related protein is induced during lethal endotoxemia and contributes to endotoxin-induced mortality in rodents
AU - Funk, Janet L.
AU - Moser, Arthur H.
AU - Strewler, Gordon J.
AU - Feingold, Kenneth R.
AU - Grünfeld, Carl
PY - 1996
Y1 - 1996
N2 - Background: Parathyroid hormone-related protein (PTHrP) is a ubiquitous and highly conserved vasoactive peptide whose role and regulation in normal physiology remain an enigma. Recently, we demonstrated that low-dose endotoxin (LPS) induces intrasplenic, but not systemic, levels of PTHrP; and that tumor necrosis factor, a pro-inflammatory cytokine, is the major mediator of this effect. We have therefore hypothesized that, with higher, lethal doses of endotoxin, PTHrP could be induced in multiple tissues to such a degree that it could contribute to the lethality of septic shock. Materials and Methods: Northern blot analysis was used to measure PTHrP mRNA levels in vital organs of rats after administration of a near lethal dose (5 mg/250 g) of LPS (or vehicle alone). Plasma levels of PTHrP were also measured by immunoradiometric assay. The ability of the immunoglobulin fraction of two different PTHrP(1-34) antisera to protect from LPS-induced lethality was also studied in mice using survival analysis. Results: In response to a near- lethal dose of endotoxin, PTHrP mRNA levels increased acutely in every vital organ examined (spleen, lung, heart, kidney, and liver). Circulating levels of PTHrP also increased, peaking 2 hr after administration of high-dose endotoxin. Passive immunization of mice with anti-PTHrP(1-34) antibody 6 hr prior to administration of a lethal dose of LPS protected mice from endotoxin-induced death (p < 0.00005). Conclusions: These results suggest that PTHrP belongs to the cascade of pro-inflammatory cytokines induced during lethal endotoxemia that is responsible for the toxic effects of LPS.
AB - Background: Parathyroid hormone-related protein (PTHrP) is a ubiquitous and highly conserved vasoactive peptide whose role and regulation in normal physiology remain an enigma. Recently, we demonstrated that low-dose endotoxin (LPS) induces intrasplenic, but not systemic, levels of PTHrP; and that tumor necrosis factor, a pro-inflammatory cytokine, is the major mediator of this effect. We have therefore hypothesized that, with higher, lethal doses of endotoxin, PTHrP could be induced in multiple tissues to such a degree that it could contribute to the lethality of septic shock. Materials and Methods: Northern blot analysis was used to measure PTHrP mRNA levels in vital organs of rats after administration of a near lethal dose (5 mg/250 g) of LPS (or vehicle alone). Plasma levels of PTHrP were also measured by immunoradiometric assay. The ability of the immunoglobulin fraction of two different PTHrP(1-34) antisera to protect from LPS-induced lethality was also studied in mice using survival analysis. Results: In response to a near- lethal dose of endotoxin, PTHrP mRNA levels increased acutely in every vital organ examined (spleen, lung, heart, kidney, and liver). Circulating levels of PTHrP also increased, peaking 2 hr after administration of high-dose endotoxin. Passive immunization of mice with anti-PTHrP(1-34) antibody 6 hr prior to administration of a lethal dose of LPS protected mice from endotoxin-induced death (p < 0.00005). Conclusions: These results suggest that PTHrP belongs to the cascade of pro-inflammatory cytokines induced during lethal endotoxemia that is responsible for the toxic effects of LPS.
UR - http://www.scopus.com/inward/record.url?scp=0029731538&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029731538&partnerID=8YFLogxK
U2 - 10.1007/bf03401617
DO - 10.1007/bf03401617
M3 - Article
C2 - 8726463
AN - SCOPUS:0029731538
SN - 1076-1551
VL - 2
SP - 204
EP - 210
JO - Molecular Medicine
JF - Molecular Medicine
IS - 2
ER -