Intracellular distribution of a cytoplasmic progesterone receptor mutant and of immunophilins cyclophilin 40 and FKBP59: effects of cyclosporin A, of various metabolic inhibitors and of several culture conditions.

The effect of cyclosporin A (CsA) on the intracellular distribution of a mutated NLS minus rabbit progesterone receptor (PRm) and the receptor-associated immunophilins, cyclophilin 40 (Cyp40) and FKBP59, was tested in Lc13 cells by indirect immunofluorescent staining. PRm, which is cytoplasmic in absence of progesterone, is shifted to the nucleus by the hormone as well as by CsA, but not by FK506 or Rapamycin [I. Jung-Testas, M.

Progesterone as a neurosteroid: synthesis and actions in rat glial cells.

The central nervous system (CNS) and the peripheral nervous system (PNS) are targets for steroid hormones where they regulate important neuronal functions. Some steroid hormones are synthesized within the nervous system, either de novo from cholesterol, or by the metabolism of precursors originating from the circulation, and they were termed 'neurosteroids'. The sex steroid progesterone can also be considered as a neurosteroid since its synthesis was demonstrated in rat glial cell cultures of the CNS (oligodendrocytes and astrocytes) and of the PNS (Schwann cells).

Neuronal signals are required for estrogen-mediated induction of progesterone receptor in cultured rat Schwann cells.

Rat glial cells from the central nervous system (CNS) and the peripheral nervous system (PNS) express steroid hormone receptors. Whereas progestin receptors (PR) in cultured glial cells of the CNS are estrogen-inducible, similar increase of PR in cultured Schwann cells, the glial cells of the PNS, prepared from newborn rat sciatic nerves, could not be demonstrated. In the present work we have used fetal dorsal root ganglion cultures to study the effect of estrogen and its antagonist ICI 164,384 on the expression of PR in rat Schwann cells.

Steroid hormone receptors and steroid action in rat glial cells of the central and peripheral nervous system.

The nervous system is a target for sex steroid hormones which have profound actions on the growth, maturation, differentiation and functioning of brain cells. We found that some steroids, termed "neurosteroids", are synthesized within the brain by glial cells. The term "neurosteroids" designates their site of synthesis--the nervous system, either de novo from cholesterol or from steroid hormone precursors.