Chorionic gonadotropin human

Glycoprotein hormone consisting of a 92-amino acid α-chain which is identical to that of LH, FSH, and TSH; and a distinct 149-amino acid β-chain. Produced by chorionic tissue and responsible for maintaining the corpus luteum during early pregnancy. Also produced by trophoblast cell neoplasms, which are marked by elevated free hCG β-chains and hyperglycosylated hCG.

Chorionic gonadotropin has been used:

• in in vitro analysis of cytotoxicity
• in egg and embryo preparations
• in the superovulation of CD-1 mice
• in gonadotropin preparations for the in vivo studies with the luteinizing hormone-releasing hormone (LHRH) agonist (LHRH-a) to synchronize naturally cycling rats.

Human chorionic gondadotropin (hCG) may be used as an alternative to PMSG to induce ovulation in laboratory animals. When hCG was injected into laboratory animals via intravenous (i.v.), intraperitoneal (i.p.), or subcutaneous (s.c.) methodstet, the effective dose values for 50% of the animals (ED50) per animal and per body weight (kg) in parenthesis were as follows:
Mice: i.v. 0.2 (7.7) I.U.; i.p. 0.3 (11.5) I.U.; s.c. 0.7 (26.9) I.U.
Syrian hamsters: i.v. 1.0 (9.5) I.U.; i.p. 1.8 (17.1) I.U.; s.c. 2.6 (24.8) I.U.
Rats: i.v. 1.3 (4.6) I.U.; i.p. 3.5 (12.3) I.U.; s.c.7.5 (26.3) I.U.

Using PMSG, the ED50 values per animal and per body weight (kg) in parenthesis were as follows:
Mice: i.v. 0.8 (30.8) I.U.; i.p. 2.0 (76.9) I.U.; s.c. 2.8 (107.7) I.U
Syrian hamsters: i.v., 3.6 (34.3) I.U.; i. p., 8.0 (76.2) I.U.; s.c., 13.2 (125.7) I.U.
Rats: i.v., 6.0 (76.8) I.U.; i p., 20.8 (73.0) I.U.; s.c., 76.8 (269.5) I.U.

When reconstituted with 10 mL water to a concentration of 1,000 IU/mL, the vial will also contain 0.01 M sodium phosphate buffer (pH approx. 7.2) and 10 mg/mL of mannitol.

The calculated value is based on the USP method for human Chorionic Gonadotrophin, to meet 10,000 IU per vial, with a tolerance of not less than 80.0% and not more than 125.0% of the potency stated.