Influence of gonadal hormones on the developing amphibian brain: changes in ribonucleic acid, protein and activity levels of acetylcholinesterase on in vivo administration of progesterone.

The levels of RNA and protein and activity levels of acetylcholinesterase decreased in the brain of developing tadpoles of 13-15-day-old Bufo melanostictus on in vivo administration of progesterone (200 mug/0.1 ml refined peanut oil). These changes suggest decelaration in the activity of the protein-synthetic machinery in progesterone administered animals.