Rosa Maigualida Maraña appeals her guilty-plea conviction and sentence for possession with intent to distribute heroine and importation of heroin. Maraña argues that the district court clearly erred in refusing to grant her request for a two-level “minor role” reduction under U.S.S.G. § 3B1.2(b). She argues that the evidence showed that she was merely a cornier and that a “recruiter” was responsible for her conduct.

The district court’s refusal to grant Marana a two-level reduction for being a minor participant was not clearly erroneous. See United States v. Virgen-Moreno, 265 F.3d 276, 296 (5th Cir. 2001). The large quantity of heroin that Maraña was transporting strongly supports the denial of a reduction for being a minor participant. See United States v. Rojas, 868 F.2d 1409, 1409-10 (5th Cir. 1989). Furthermore, the district court was not required to accept Marana’s account of her role in the drug trafficking scheme. See United States v. Buenrostro, 868 F.2d 135, 138 (5th Cir. 1989). Lastly, this court has held that “couriers are an *762 indispensable part of drug dealing networks.” Id.

For the first time on appeal, Maraña maintains that the sentencing schemes of 21 U.S.C. §§ 841 and 846 are unconstitutional in light of Apprendi v. New Jersey, 530 U.S. 466, 490, 120 S.Ct. 2348, 147 L.Ed.2d 435 (2000). As Maraña concedes, her argument is foreclosed by this court’s decision in United States v. Slaughter, 238 F.3d 580, 582 (5th Cir. 2000). She raises the issue only to preserve it for possible further review.

The judgment of the district court is AFFIRMED.