In vitro progesterone and estradiol -17B synthetic ability of the isolated luteal cells in wistar rats and cynomolgus monkeys

Abstract

The purpose of this study is to determine the functional capacity of rat’s and cynomolgus monkey’s isolated luteal cells on secretion of P and E₂ in short term and long term experiment and to compare responsiveness of these cells to potential corpus luteum regulating agents including hCG, PRL, and PGF₂∝, either alone or incombination, during various physiological states. The study was conducted in the normal cycle of rats and monkeys; pseudopregnancy, pregnancy and lactating period of rats. The corpora lutea were treated with 0.1% of collagenase by method of Sala et al. (1979). The isolated luteal cells were incubated under 5% CO₂ and 95% humidified air at 37℃, for 3 hours 1, 3, 5, 7, 9 and 11 days, respectively. The results indicate that isolated luteal cells of rat and monkey are capable to survive and secrete P and E₂ independent of hormone administration for at least 7 days. Administration of hCG during active luteal phase significantly enhanced the production of P and E₂ from isolated luteal cells of rat and monkeys. PRL was significantly capable to stimulate P secretion from rat luteal cells not the monkey and may acts synergistically with hCG. PGF₂∝, on the otherhand, was capable to stimulate long term P production from luteal cells of young CL of rats and monkeys but enhanced luteolysis in those from aged CL of both species. It is concluded that hCG and related gonadotrophins may act as a universal luteotrophic agent in placental mammals while PRL has a limitation on stimulation of P production in small laboratory rodents and related primitive placental mammals. Finally, PGF₂∝, may act as an intraluteal regulators in several mammalian species.