Send to

Choose Destination
Endocrinology. 1989 Sep;125(3):1666-72.

Activin-A, inhibin and transforming growth factor-beta modulate growth of two gonadal cell lines.

Author information

Clayton Foundation Laboratories for Peptide Biology, Salk Institute, La Jolla, California 92037.


The proliferative and differentiating effects of the gonadal hormones inhibin and activin-A were examined on cell lines derived from the ovary and testis. Activin-A was found to inhibit the growth of CHO-K1 (Chinese hamster ovary) cells in culture, with an IC50 of 3 ng/ml. The maximal response (50% inhibition) required 3 days of incubation in the presence of 40 ng/ml activin-A, and the inhibitory effect was accompanied by morphological changes. Inhibin (10 ng/ml) partially blocked the inhibition of growth by activin. Transforming growth factor-beta (TGF beta), which is structurally related to activin and inhibin, was a very potent inhibitor of the proliferation of CHO-K1 cells, with an IC50 of 0.2 ng/ml and a maximal effect (70% inhibition) at 2 ng/ml. The combination of high concentrations of both TGF beta and activin-A did not result in a greater inhibitory effect than that observed with TGF beta alone, suggesting an overlapping step in the mechanism of action for both factors. In contrast to the results with CHO-K1 cells, differential effects of activin-A and TGF beta were observed in R2C (rat Leydig cell testicular tumor) cells. Activin-A had only a slight effect on proliferation over a 4-day incubation, but inhibited progesterone accumulation ina concentration-dependent fashion within 12 h. TGF beta, on the other hand, was a potent inhibitor of both growth and steroidogenesis in R2C cells. These studies suggest that activin-A and inhibin may regulate proliferation as well as functions of gonadal cells.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center