Low-dose dexamethasone ameliorates circulatory failure and renal dysfunction in conscious rats with endotoxemia.
Corticosteroids have long been proposed as a therapeutic adjuvant in septic renal dysfunction because of their anti-inflammatory properties and favorable results from animal experiments. However, some reports suggested the potential for harm associated with the administration of early high-dose corticosteroids in patients with severe sepsis and septic shock. Thus, we examined the effects of low-dose dexamethasone (0.01 and 0.1 mg/kg) on hemodynamics and renal function in conscious rats with endotoxemia. Intravenous injection of rats with endotoxin (E. coli lipopolysaccharide, LPS, 1 mg/kg) caused hypotension, vascular hyporeactivity, and tachycardia as well as renal dysfunction. Circulatory failure and renal dysfunction caused by LPS were significantly attenuated in the dexamethasone 0.1 mg/kg-treated group. The nitric oxide (NO) production in plasma and renal tissue and the iNOS protein expression in the kidney were suppressed by cotreatment of LPS rats with dexamethasone, 0.1 mg/kg. Light microscopy showed that 0.1 mg/kg dexamethasone reduced marked infiltration of neutrophils in renal tissues from LPS rats. Moreover, the survival rate at 18 h was significantly increased in the dexamethasone 0.1 mg/kg-treated group when compared with the LPS group. These results suggest that the beneficial effects of low-dose dexamethasone (0.1 mg/kg) in conscious rats with endotoxic shock are associated with amelioration of circulatory failure and renal dysfunction, and this is attributed to inhibition of NO production.
Tsao
Cheng-Ming
CM
Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Republic of China, Taiwan.
Ho
Shung-Tai
ST
Chen
Ann
A
Wang
Jhi-Joung
JJ
Li
Chi-Yuan
CY
Tsai
Shen-Kou
SK
Wu
Chin-Chen
CC
D000818:Animals; D001158:Arteries / Q000378:metabolism; D001794:Blood Pressure; D015153:Blotting, Western; D002118:Calcium / Q000097:blood; D003907:Dexamethasone / Q000627:therapeutic use*; D019446:Endotoxemia / Q000188:drug therapy*; D004926:Escherichia coli / Q000378:metabolism; D005938:Glucocorticoids / Q000627:therapeutic use; D006863:Hydrogen-Ion Concentration; D007668:Kidney / Q000293:injuries* / Q000382:microbiology* / Q000473:pathology; D008070:Lipopolysaccharides / Q000378:metabolism; D008297:Male; D009504:Neutrophils / Q000378:metabolism; D009566:Nitrates / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D011188:Potassium / Q000097:blood; D051381:Rats; D017208:Rats, Wistar; D018805:Sepsis / Q000188:drug therapy; D012772:Shock, Septic / Q000628:therapy; D013610:Tachycardia; D013997:Time Factors
D005938:Glucocorticoids; D008070:Lipopolysaccharides; D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide; D003907:Dexamethasone; D011188:Potassium; D010100:Oxygen; D002118:Calcium