The effect of magnesium on the fine structure of the golden hamster parathyroid gland in vivo and in vitro.

We examined the effect of magnesium (Mg) on the fine structure of the golden hamster parathyroid gland in vivo and in vitro. In the in vivo study, the principal changes in the parathyroid glands 10 and 30 min, and 1 hr after Mg injection showed a significant decrease in the area of the Golgi apparatus and cisternae of the rough endoplasmic reticulum compared with those of the control animals. The serum calcium level in the experimental animals 30 min and 1 hr after the injection was significantly low compared with that of the control animals. In the vitro study, the area of the Golgi apparatus in the Mg-treated group significantly decreased as compared with that of the control group. These changes suggest that Mg directly suppresses the synthesis of hamster parathyroid hormone in the short term.