Unilateral nephrectomy causes an abrupt increase in inflammatory mediators and a simultaneous decrease in plasma...

Area of Science:

• Biochemistry
• Physiology
• Immunology

Background:

• Asymmetric dimethylarginine (ADMA) inhibits nitric oxide synthases (NOS).
• Reducing inducible NOS activity is desirable in acute inflammation.
• In vitro studies show ADMA increases with inflammatory mediators, but in vivo effects are less studied.

Purpose of the Study:

• To evaluate plasma ADMA levels before, during, and after an acute inflammatory-like state.
• To investigate the in vivo effects of acute inflammation on ADMA and l-arginine.

Main Methods:

• Plasma ADMA, l-arginine, C-reactive protein, and IL-6 were measured in 24 healthy subjects undergoing living related kidney donation.
• Measurements were taken before surgery and at multiple time points up to 168 hours post-nephrectomy.

Main Results:

• ADMA levels decreased 6 and 24 hours after nephrectomy, with IL-6 peaking at 24 hours.
• ADMA levels were elevated 7 days post-surgery.
• l-Arginine levels decreased early post-surgery and increased significantly by day 7.
• The l-arginine/ADMA ratio, indicating NO production capacity, was altered for less than 24 hours.

Conclusions:

• This is the first study demonstrating temporary decreases in both ADMA and l-arginine after unilateral nephrectomy, coinciding with increased inflammatory mediators.
• The findings provide new insights into the dynamic changes of ADMA and l-arginine in response to acute inflammation in vivo.