Pituitary actions of ligands of the TGF-beta family: activins and inhibins.
Activins, as members of the transforming growth factor-beta superfamily, control and orchestrate many physiological processes and are vital for the development, growth and functional integrity of most tissues, including the pituitary. Activins produced by pituitary cells work in conjunction with central, peripheral, and other local factors to influence the function of gonadotropes and maintain a normal reproductive axis. Follistatin, also produced by the pituitary, acts as a local buffer to bind activin and modulate its bioactivity. On the other hand, inhibins of gonadal origin provide an endocrine feedback signal to antagonize activin signaling in cells that express the inhibin co-receptor, betaglycan, such as gonadotropes. This review highlights the pituitary roles of activin and the mechanisms through which these actions are modulated by inhibin and follistatin.
Bilezikjian
Louise M
LM
The Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, 10010 N. Torrey Pines Road, La Jolla, California 92037, USA. bilezikjian@salk.edu
Blount
Amy L
AL
Donaldson
Cindy J
CJ
Vale
Wylie W
WW
D028341:Activins / Q000378:metabolism*; D000818:Animals; D005260:Female; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D038681:Follistatin / Q000378:metabolism; D006801:Humans; D007265:Inhibins / Q000378:metabolism*; D008297:Male; D010902:Pituitary Gland / Q000378:metabolism*; D012098:Reproduction / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D016212:Transforming Growth Factor beta / Q000378:metabolism*
D038681:Follistatin; D016212:Transforming Growth Factor beta; D028341:Activins; D007265:Inhibins; D005640:Follicle Stimulating Hormone