Female sex hormones protect red blood cells from damage after trauma-hemorrhagic shock.
BACKGROUND
Trauma/hemorrhagic shock (T/HS) is known to cause changes in red blood cell (RBC) deformability and resting shape. Our previous studies have shown that proestrus female rats are more protected from shock-induced RBC damage than diestrus females or males. However, it is unclear whether female or male sex hormones can influence the severity of these alterations.


METHODS
Red blood cell deformability and shape were examined in proestrus female rats, and oophorectomized female rats, as well as in castrated and non-castrated male rats (5-10 animals per group) subjected to T/HS. Red blood cell deformability was measured by laser ektacytometry whereas erythrocyte shape was evaluated by scanning electron microscopy.


RESULTS
Proestrus female rats subjected to T/HS did not show either significant RBC deformability changes (decrease in elongation index) or shape alterations (increase in the percentage of reversibly and irreversibly changed cells). Oophorectomized rats demonstrated more severe RBC changes than did non-oophorectomized rats. The degree of RBC damage was the same in castrated and non-castrated males, which was significantly worse than in proestrus females.


CONCLUSIONS
Removal of female sex hormones increases the severity of T/HS-induced RBC changes, indicating that female sex hormones protect against RBC damage. In contrast, male sex hormones do not appear to modulate T/HS RBC dysfunction.
Zaets
Sergey B
SB
Department of Surgery, UMDNJ-New Jersey Medical School, Newark, New Jersey 07103, USA. zaets001@hotmail.com
Berezina
Tamara L
TL
Xu
Da-Zhong
DZ
Lu
Qi
Q
Cohen
David
D
Deitch
Edwin A
EA
Machiedo
George W
GW
D000704:Analysis of Variance; D000818:Animals; D002369:Castration; D004195:Disease Models, Animal; D004907:Erythrocyte Deformability / Q000187:drug effects / Q000502:physiology*; D004912:Erythrocytes / Q000502:physiology / Q000648:ultrastructure*; D005260:Female; D012739:Gonadal Steroid Hormones / Q000494:pharmacology*; D008297:Male; D008855:Microscopy, Electron, Scanning; D010052:Ovariectomy; D011336:Probability; D051381:Rats; D012680:Sensitivity and Specificity; D012771:Shock, Hemorrhagic / Q000503:physiopathology*
D012739:Gonadal Steroid Hormones