Hypertonic saline, mannitol and hydroxyethyl starch preconditioning of platelets obtained from septic patients attenuates CD40 ligand expression in vitro.
BACKGROUND
Because platelet CD40 ligand (CD40L) expression plays an important role in inflammatory conditions, reduction of CD40L expression may be beneficial for patients with sepsis. Although hypertonic saline, mannitol, and hydroxyethyl starch (HES) solutions have been shown to modulate inflammatory responses, their effects on platelet CD40L expression are unclear. We assessed the effects of hypertonic saline, mannitol, and HES solutions on platelet CD40L expression.


METHODS
Platelet-rich plasma samples were obtained from septic patients and diluted to 1%, 2.5%, 5%, or 7.5% (vol/vol) with 7.5% saline, 3% saline, 0.9% saline, 20% mannitol, 10% HES (200/0.5), or Ringer's solution. Twenty-five samples were used per dilution. To determine platelet CD40L expression, platelet samples were stimulated with thrombin (0.1 U/mL), incubated with fluorochrome-conjugated platelet antibodies, and analyzed using flow cytometry.


RESULTS
Preconditioning of platelet-rich plasma with hypertonic saline, mannitol, and HES attenuated CD40L expression at dilution ratios of 5%, 1%, and 1%, respectively. The decreases were concentration dependent. The effects of mannitol and HES on CD40L expression were almost identical and were superior to those of 3% saline. In contrast, 0.9% saline and Ringer's solution had no effect on CD40L expression.


CONCLUSIONS
Our data show that resuscitation fluids, such as hypertonic saline, mannitol, and HES, inhibit agonist-induced CD40L expression on platelets. These resuscitation fluids may have an anti-inflammatory action when administered to septic patients.
Huang
Go-Shine
GS
Department of Anesthesiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
Shih
Chien-Ming
CM
Wu
Chin-Chen
CC
Hu
Mei-Hua
MH
Tsai
Chien-Sung
CS
Liaw
Wen-Jinn
WJ
Chan
Shun-Ming
SM
Li
Chi-Yuan
CY
D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism*; D023201:CD40 Ligand / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006438:Hemodilution; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology*; D008353:Mannitol / Q000494:pharmacology*; D012462:Saline Solution, Hypertonic / Q000494:pharmacology*; D018805:Sepsis / Q000378:metabolism*
D006895:Hydroxyethyl Starch Derivatives; D012462:Saline Solution, Hypertonic; D023201:CD40 Ligand; D008353:Mannitol