Are the parathyroid glands necessary to the life of the newt, Cynops pyrrhogaster?

In contrast to the diverse results of parathyroidectomy in anurans as to the appearance of neuromuscular symptom, effects of the removal of parathyroid glands in urodeles have been in agreement with each other. Scholz (1935) working with Salamandra, reported that his animals were kept in his laboratory up to 1 year after parathyroidectomy without any ill effect. Parathyroidectomy in Triton and Triturus also failed to cause neuromuscular symptoms (Cortelyou, 1967, unpubl. data; Studitsky, 1945). In the newt, Cynops pyrrhogaster, the author found that parathyroidectomy induced tetany only in about 10% of the operated animals and the majority of the remainder were free from neuromuscular abnormality, although the serum calcium concentration declined to about half of the normal level (Oguro, 1969). In that report, it was described that the earliest parathyroidectomized specimens had been kept in the author's laboratory for more than 800 days. Recently, about 1,000 days after parathyroidectomy, those specimens were sacrificed to check on the effects of long-term parathyroprivation, especially on serum calcium concentration. Material and Methods