[Participation of thyrocalcitonin in the development of stress]

The immobilization stress in rats entailed raise of calcium content in the plasma followed by a decrease to the hypocalcaemic level. The thyrocalcitonin activity of plasma was undetectable in intact rats, but increased to 5 mU/ml after 3 hrs of stress. Administration of bovine thyrocalcitonin (10 U/100 g) before the immobilization inhibited the lowering of CRF activity of hypothalamic extracts, ACTH content of hypophysis, and ascorbic acid concentration in adrenal glands of the rats under stress, i.e. inhibited the development of stress reaction.