Arck P C, Merali F S, Manuel J, Chaouat G, Clark D A
Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
Am J Reprod Immunol. 1995 Jan;33(1):74-80. doi: 10.1111/j.1600-0897.1995.tb01141.x.
Stress adversely affects pregnancy outcome and has been implicated as an abortogen in both animals and humans. However, the mechanisms whereby stress aborts are largely unknown. Alloimmunization can prevent stress-triggered abortion, and immunization is known to increase transforming growth factor-beta 2 (TGF-beta 2)-related suppressive activity.
To investigate these mechanisms, DBA/2J males were mated to CBA/J or C3H/HeJ females, and the pregnant females were exposed to ultrasonic sound stress for a period of 24 h between day 4.5 to 8.5 of pregnancy.
Ultrasonic stress significantly elevated the resorption rate with a peak effect on day 5.5 in the CBA/J females and on day 4.5 in the LPS-resistant C3H/HeJ females. The tumor necrosis factor-alpha (TNF-alpha) release from the decidua was also elevated and the TGF-beta 2-mediated suppressive activity was significantly decreased. The resorption rate only increased when the TNF-alpha/TGF-beta 2 ratio was increased compared to the control.
These data suggest that stress may inhibit protective suppressor mechanisms and promote secretion of abortogenic cytokines such as TNF-alpha. Possible mechanisms are discussed.
