Effects of TAP-144-SR, a sustained-release formulation of a potent GnRH agonist, on experimental endometriosis in the rat.
A new, simple experimental endometriosis model was established by auto-transplanting endometrial tissue fragments beneath kidney capsules in female rats. The transplanted endometrial tissue grew well, forming a fluid-filled cyst, which reached maximal size 2 to 3 weeks after transplantation. The growth and maintenance of the transplants was dependent on the ovary: ovariectomy induced regression of well grown transplants. The therapeutic effects of TAP-144-SR (biodegradable microcapsules of copoly (DL-lactic/glycolic acid) copolymer containing a potent GnRH agonist, TAP-144 (D-Leu6-[des-Gly10-NH2]-GnRH ethylamide, leuprolide acetate) were studied with this rat endometriosis model. A single sc injection of TAP-144-SR (corresponding to 1, 10 or 100 micrograms/kg/day of TAP-144), suppressed the growth of the transplanted endometrial tissues and uterine weight in a dose-dependent manner. At 100 micrograms/kg/day, the suppressive effect was more marked in rats given TAP-144-SR than in those given TAP-144 solution. The extent of suppression was comparable to that caused by ovariectomy. Serum and pituitary concentrations of LH and FSH were also reduced more markedly by the administration of TAP-144-SR than by TAP-144 solution. From these results, the present endometriosis model was found to be useful for the evaluation of compounds with potential therapeutic activity. The sustained-release formulation of TAP-144 seems to be beneficial over its solution in terms of both convenience and efficiency for therapy of patients with endometriosis.
Biology Research Laboratories, Takeda Chemical Industries, Ltd., Osaka, Japan.
K
K
Sudo
K
K
Shiota
T
T
Masaki
T
T
Fujita
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D003692:Delayed-Action Preparations; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004715:Endometriosis / Q000188:drug therapy*; D004717:Endometrium / Q000187:drug effects / Q000637:transplantation; D005260:Female; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D016729:Leuprolide / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D010052:Ovariectomy; D010053:Ovary / Q000033:anatomy & histology; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014594:Uterine Neoplasms / Q000188:drug therapy*; D014599:Uterus / Q000033:anatomy & histology
D000970:Antineoplastic Agents; D003692:Delayed-Action Preparations; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D016729:Leuprolide