Therapeutic efficiency of Atosiban, an oxytocin receptor blocking agent in the treatment of experimental endometriosis.

PURPOSE: The current study investigated the potential therapeutic efficiency of atosiban, an oxytocin receptor antagonist, in an experimental endometriosis model.

METHODS

Endometriosis was surgically induced in 35 female rats during estrus. Four weeks after this procedure, relaparotomy was performed. The viability and dimensions of the endometriosis foci were recorded. Rats were then randomly divided into three groups. In the first group (n = 8), a daily dose of 0.2 ml 0.9 % NaCl was injected intraperitoneally (i.p.) (control cases). In the second and third groups (n = 8 and n = 8), 0.5 mg/kg/day i.p. atosiban and 1 mg/day i.p. diltiazem were given, respectively. At the end of the treatment, laparotomy was performed, and the dimensions of the endometriosis foci were recorded. The endometrial implants were processed for histological and immunohistochemical studies. The volumes of endometriotic implants were measured, and immunohistochemical analyses were performed, and compared between the groups.

RESULTS

After the treatment with atosiban, volumes of endometriotic implants decreased significantly. Proliferating cell nuclear antigen expression levels were significantly reduced in the atosiban and diltiazem groups compared with the control group.

CONCLUSIONS

In a rat endometriosis model, atosiban, an agent used for the first time for the medical treatment of endometriosis, has shown significant therapeutic efficiency.