AJP - Cell Physiology, Vol 248, Issue 5 425-C435, Copyright © 1985 by American Physiological Society
Regulation of hormonal responsiveness in LLC-PK1L cells grown in defined medium
C. Roy
LLC-PK1L cells, a kidney-derived cell line, were able to grow in a
chemically defined medium. Growth of the cells in the presence of retinol,
ergocalciferol, d-alpha-tocopherol, 3,3',5-triiodothyronine,
hydrocortisone, l-carnitine, d-l-methionine-S-methylsulfonium chloride,
insulin, transferrin, cholesterol, and sodium linoleate increased the
number of vasopressin receptors by 20- to 40-fold. All the newly detectable
vasopressin receptors were coupled to the adenylate cyclase activity with
similar efficiency. The same growth conditions did not alter the basal
adenylate cyclase activity or the responses to calcitonin, parathyroid
hormone, prostaglandin, adenosine, and GTP. In contrast, the increased
responsiveness of the adenylate cyclase to vasopressin was associated with
a reduced response to isoproterenol. Such an inverse correlation was also
found when the time course of vasopressin receptor induction was studied.
The supplemented medium permitted the growth of cells for several weeks.
The effects of the enriched medium were fully reversible when we returned
to the original cell growth medium. Thus such a cellular system appears as
a useful tool for further work in cellular and kidney endocrinology and for
detailing the molecular mechanisms of receptor-adenylate cyclase
regulations.
