Observations on the fine structure of propylthiouracil‐induced “brown degeneration” in the zona reticularis of mouse adrenal cortex

Abstract

Propylthiouracil (6-propyl-2-thiouracil), an anti-thyroid agent, was fed to mice in a concentration equal to 0.1% of their diet for periods of 10 and 15 weeks. The cells of the inner zone of the adrenal cortex were examined with the electron microscope. In animals receiving propylthiouracil for ten weeks mitochondria were altered and the smooth endoplasmic reticulum (SER) showed a marked focal proliferation. In contrast to control animals rough endoplasmic reticulum was abundant and was frequently associated with the hyperplastic SER. After 15 weeks these alterations were no longer present but had been replaced by a spectrum of "brown degeneration." The less affected cells were characterized by increased numbers of liposomes and lysosomes and the more affected cells by liposomal and mitochondrial degeneration. These observations emphasize that "brown degeneration" is a true degenerative process and not a spontaneous proliferation of ceroid pigment. It is suggested that the changes described may be directly related to an alteration in cholesterol metabolism.

The role of peroxisomal ABC transporters in the mouse adrenal gland: the loss of Abcd2 (ALDR), Not Abcd1 (ALD), causes oxidative damage

“…It is enhanced by a dietary deficiency in antioxidants, such as vitamin E, 23 or when mitochondrial damage is induced with propylthiouracil in the rodent 24 and with o, p 0 dichlorodiphenyldichloroethane (DDD) in the dog. 25 In both the propylthiouracil-induced brown degeneration in the mouse adrenal and the o, p 0 DDD intoxication of the dog adrenal, early abnormalities in mitochondrial ultrastructure (ie, swelling and loss of cristae) and ultimately their loss have been reported.…”

Specific Lamellar Structures of Agranular Endoplasmic Reticulum in the Senile Mouse Adrenal Cortex

“…Subsequently, one of the figures of the reticularis cell of mouse adrenal cortex by MOORE and CALLAS (1975) shows a straight lamellar body but without any comment on it. Recently FUJITA (1977) described the same sort of body in an old mouse aged 22 months.…”

“…Specific lamellar structures of agranular endoplasmic reticulum occasionally appear in adrenal cortical cells of mice (SATO, 1967;SHELTON and JONES, 1971;MOORE and CALLAS, 1975;FUJITA, 1977), but their detailed ultrastructure has not yet been elucidated. During the course of an electron microscopic study of senile mouse adrenal glands, highly organized lamellar structures were frequently encountered in parenchymal cells of the inner zone of the cortex.…”

Atrophy of the zona fasciculata in the adrenal cortex of thyroparathyroidectomized rats: A quantitative study

“…The study of Callas (1971) and the present study are, to the best of our knowledge, the only two reports on the effect of hypothyroidism on the fine structure of the zona fasciculata. A reason for the difference between the two studies may be that antithyroid agents, such as propylthiouracil, have a direct effect on the adrenal gland, in ad-dition to inhibiting thyroid function (Money, 1955;Pittman, 1971;Moore and Callas, 1975). Therefore, it is difficult to determine if reported effects are attributable to the absence of thyroid hormone or are due to a direct effect of the drug on the gland.…”

“…In contrast, Zarrow and Money (1949), Money (1955), and McCarthy et al (1958) found a highly significant decrease in relative weight of the adrenal gland in thiouracil-induced hypothyroidism. A drawback in interpreting some of the previous studies, which could explain in part the different results, is that antithyroid agents may have a direct effect on the adrenal gland (Money, 1955;Pittman, 1971; Moore and Callas, 1975). Thyroparathyroidectomy obviates the use of such agents; recently, we reported a decrease in relative weight of the adrenal gland in rats made hypothyroid by surgical thyroparathyroidectomy (TPX; Conran and Nickerson, 1979).…”