Vol. 24 (5) 2003 Neuro endocrinology letters

Melatonin does not affect p21 expression in rat thyroid follicular cells.

OBJECTIVES: The cell-cycle (cc) is, in part, controlled by cyclin-dependent kinases (CDKs), which are activated after binding cyclins (positive regulators of cc). CDK inhibitors (CDKIs), such as p15, p16, p21, and p27, inhibit cyclin-CDK complex activity, and function as negative cell cycle regulators, blocking cell-cycle progression. T.....