Abstract
Microscopic studies were carried out on three groups of Mongolian gerbils: one experimental
group receiving PTE injections; another experimental group receiving PTE and calcium
injections; and one control group receiving saline injections. Hypercalcemia was recorded
in both experimental groups after the injections, whereas the controls remained normocalcemic.
Light microscopically the parathyroid glands from all animal groups showed a similar
picture of sheets of chief cells with varying cytoplasmic density. Ultrastructural
examination disclosed in all animal groups chief cells with varying electron density
and content of organelles; in the experimental animals, however, there was a preponderance
of cells with inconspicuous Golgi complex and endoplasmic reticulum and also many
cells with structurally altered mitochondria. It is concluded that although injections
of PTE and calcium results in functional inactivity in many parathyroid cells, it
is not possible to induce a complete inactivity or atrophy in intact animals by this
kind of treatment. This might be due to the existence of a functional cyclus in the
parathyroid cells or to effects of calcitonin.
Key words
Mongolian Gerbil - Parathyroid Glands - Parathormone - Calcium - Light and Electron
Microscopy - Functional Activity - Mitochondria
1 Supported by grants from the Swedish Research Council (Projects No. B73-17X-3499-02
and B74-17X-3499-03) and the Medical Research Council of the Swedish Life Offices.
