Prompt Recovery of Damaged Adrenal Medullae Induced by Salinomycin

Abstract

The morphologic changes in the adrenal medullae of rats treated with an ionophore antibiotic, salinomycin, are described. Male rats of approximately 7 wk of age were treated orally with a single dose of salinomycin at 80 mg/kg body weight. Following this treatment, the adrenal glands were examined, using immunohistochemistry, for neurofilament, laminin, fibronectin, and S-100 protein; the glands were also examined using transmission electron microscopy. One hour after the treatment, a karyopyknosis was observed in the clusters of affected chromaffin cells in which the neurofilament, laminin, and fibronectin were present. The lesions became progressively conspicuous between hours 5 and 10. Ultimately, the outcome was cell lysis. Five hours after salinomycin treatment, unaffected chromaffin cells strongly stained to tyrosine hydroxylase. At 10 hr, new chromaffin cells, which were irregular in shape with electron-dense cytoplasm (dark cell), that were strongly stained for tyrosine hydroxylase appeared at the basement membrane site of the necrotic clusters, and these cells contained very few immature catecholamine granules of less than 80 nm. At 17 hr, the catecholamine granules increased in number and size to about 200 nm. The newly formed chromaffin cells grew within the clusters to fill in the medulla by 24 hr, and cytoplasmic granules progressively increased in number and size. The interstitial tissue was seen to be edematous at 5 hr. New capillaries were found in the adrenal medullae of both control and salinomycin-treated rats. The protruding chromaffin cells (protruding cells), which we previously described in normal rats, were also observed in salinomycin-treated rats, which suggests that holocrine secretion is performed in the adrenal medullae. The results indicated that the rat adrenal medullae have the ability to make a rapid recovery after an insult by salinomycin.

Insights into the Localization and Function of the Membrane Trafficking Regulator GNOM ARF-GEF at the Golgi Apparatus inArabidopsis

“…After treatment with 10 µM monensin for 30 min, GNOM-GFP-labeled compartments and ST-mRFP-labeled Golgi apparatus were strongly enlarged and were also colocalized ( Figure 3G; Supplemental Figures 4G to 4I). Similar results ( Figure 3H; Supplemental Figures 4J to 4L) were obtained when we applied 10 µM salinomycin for 30 min, a monovalent cation ionophore that is assumed to function similarly to monensin (Chen-Pan et al, 1999). We also confirmed that the Golgi marker, ST-mRFP, behaves in a similar manner to GNOM-GFP after treatment with the Wm and ConcA (Supplemental Figures 5A to 5C).…”

Recovery of Injured Adrenal Medulla by Differentiation of Pre-Existing Undifferentiated Chromaffi n Cells

“…The Schwann cells were closely associated with nerve bers (Figure 5a, b, d). Other features were similar to those previously described (1).…”

“…Undifferentiated chromaf n cells, previously called pheochromoblasts became apparent 10 hours after administration of salinomycin/kg 80 mg of body weight, with electron dense cytoplasm due to the presence of numerous free ribosomes and catecholamine granules less than 80 nm in diameter. After 17 hours, only differentiated chromaf n cells were observed, with full morphological recovery at 24 hours (1).…”

The development of adrenal homolog of rainbow trout Oncorhynchus mykiss: an immunohistochemical and ultrastructural study

“…Because we never observed differentiated chromaffin cells in mitosis, we can hypothesize that the increase in number of these cells during development is due to a proliferation of undifferentiated precursors present in the kidney. Chen-Pan et al (1999) in fact demonstrated that in rat adrenal medulla damaged by salinomycin, new chromaffin cells differentiate from unrecognized precursors present in the medullary tissue.…”