Ultrastructural Evaluation of the Parathyroid Glands of Pigs with Naturally Occurring Atrophic Rhinitis

Abstract

The secretory activity of the parathyroid glands of 4-month-old pigs with naturally occurring atrophic rhinitis was evaluated ultrastructurally and compared to control pigs of the same age. The principal difference between the 2 groups was a transformation of the predominately inactive chief cell population in control pigs into chief cells of a more active stage of their secretory cycle in diseased pigs. The active chief cells in pigs with atrophic rhinitis had an electron-dense cytoplasm, large Golgi apparatuses, aggregated ribosomes, and abundant endoplasmic reticulum. Secretory granules occurred in increased numbers in the active chief cells of diseased pigs compared to control pigs. The degree of parathyroid stimulation appeared to be mild in pigs with atrophic rhinitis and the stimulative effects seemed to be greater on hormonal synthesis than on hormonal secretion. There was no evidence of severe or prolonged parathyroid stimulation.