702
challenged this view and suggested that the primary role of the parathyroid gland is the regulation of acid-base homoeostasis. His hypothesis was based in part upon the fact that the parathyroid gland appeared late in evolution, when vertebrates first came on land. Fishes and man both have true calcium-phosphate bone, yet the fish regulates calcium metabolism differently. Blood-calcium levels in the fish seem to be maintained predominantly via hormones produced by the pituitary (prolactin for one) and by calcitonin and vitamin D. Since man has all three is it necessary that a fourth (parathyroid hormone) be the predominant one in the regulation of calcium metabolism merely because of the evolution to an air environment from a water one? I think not. The Clarias species of catfish which has propagated in Florida for the past nine years can live on land for up to an hour as well as in its natural habitat; it has no parathyroid glands. Although this does not prove that the parathyroid glands are not the dominant organ in the regulation of calcium metabolism, the very nature of an animal with a true calcium-phosphorus bone whose calcium is regulated by factors other than the parathyroids may hold a key to further understanding of derangements in calcium metabolism and/or parathyroid function. Department of Pathology,
augmentation of tuberculin skin-test positivity there difference between levamisole and placebo groups. By the end of the third month 1 of the 23 levamisole treated and 8 of the 27 control patients had not recovered from the acute disease, as judged by transaminases, HBsAg, and/or hisIn the
was no
tology (P
challenged this view and suggested that the primary role of the parathyroid gland is the regulation of acid-base homoeostasis. His hypothesis was based in part upon the fact that the parathyroid gland appeared late in evolution, when vertebrates first came on land. Fishes and man both have true calcium-phosphate bone, yet the fish regulates calcium metabolism differently. Blood-calcium levels in the fish seem to be maintained predominantly via hormones produced by the pituitary (prolactin for one) and by calcitonin and vitamin D. Since man has all three is it necessary that a fourth (parathyroid hormone) be the predominant one in the regulation of calcium metabolism merely because of the evolution to an air environment from a water one? I think not. The Clarias species of catfish which has propagated in Florida for the past nine years can live on land for up to an hour as well as in its natural habitat; it has no parathyroid glands. Although this does not prove that the parathyroid glands are not the dominant organ in the regulation of calcium metabolism, the very nature of an animal with a true calcium-phosphorus bone whose calcium is regulated by factors other than the parathyroids may hold a key to further understanding of derangements in calcium metabolism and/or parathyroid function. Department of Pathology,
augmentation of tuberculin skin-test positivity there difference between levamisole and placebo groups. By the end of the third month 1 of the 23 levamisole treated and 8 of the 27 control patients had not recovered from the acute disease, as judged by transaminases, HBsAg, and/or hisIn the
was no
tology (P
