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Churukian CJ, Rubio A, Lapham LW. A Simple Colloidal Silver Method (Autometallographic Technique) for Demonstrating Inorganic Mercury in Brain Sections. J Histotechnol 2013. [DOI: 10.1179/his.2000.23.4.337] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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2
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Soto M, Quincoces I, Marigómez I. Autometallographical Procedure for the Localization of Metal Traces in Molluscan Tissues by Light Microscopy. J Histotechnol 2013. [DOI: 10.1179/his.1998.21.2.123] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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3
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Danscher G, Montagnese C. Autometallographic Localization of Synaptic Vesicular Zinc and Lysosomal Gold, Silver and Mercury. J Histotechnol 2013. [DOI: 10.1179/his.1994.17.1.15] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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4
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Roos PM, Dencker L. Mercury in the spinal cord after inhalation of mercury. Basic Clin Pharmacol Toxicol 2012; 111:126-32. [PMID: 22364490 DOI: 10.1111/j.1742-7843.2012.00872.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2011] [Accepted: 02/08/2012] [Indexed: 12/25/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) affects anterior horn cells of the spinal cord causing an indolent slow and steady deterioration of muscle strength leading inevitably to death in respiratory failure. ALS is a model condition for neurodegenerative disorders. Exposure to different agents dispersed in the environment has been suggested to cause neurodegeneration but no convincing evidence for such a link has yet been presented. Respiratory exposure to metallic mercury (Hg(0)) from different sources may be suspected. Body distribution of metallic mercury is fast and depends on solubility properties. Routes of transport, metabolism, excretion and biological half-life determine the overall toxic effects. Inhalation experiments were performed in 1984 where small marmoset monkeys (Callithrix jacchus) were exposed to (203) Hg(0 vapour) mixed into the breathing air (4-5 μg/l). After 1 hr of exposure, they were killed and whole body autoradiograms prepared to study the distribution of mercury within organs. Autoradiograms showed that Hg was deposited inside the spinal cord. Areas of enhanced accumulation anatomically corresponding to motor nuclei could be observed. This study describes a reinvestigation, with new emphasis on the spinal cord, of these classical metal exposure data in a primate, focusing on their relevance for the causation of neurodegenerative disorders. A comparison with more recent rodent experiments with similar findings is included. The hypothesis that long-time low-dose respiratory exposure to metals, for example, Hg, contributes to neurodegenerative disorders is forwarded and discussed.
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Affiliation(s)
- Per M Roos
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
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Schiønning JD. Experimental neurotoxicity of mercury Autometallographic and stereologic studies on rat dorsal root ganglion and spinal cord. APMIS 2011. [DOI: 10.1111/j.1600-0463.2000.tb05696.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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6
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Son HY, Lee S, Park SB, Kim MS, Choi EJ, Singh TS, Bae Y, Kwack SJ, Kang TS, Shin HI, Baek MC, Kim SH. Toxic effects of mercuric sulfide on immune organs in mice. Immunopharmacol Immunotoxicol 2009; 32:277-83. [DOI: 10.3109/08923970903305499] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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7
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Stankovic R. Atrophy of Large Myelinated Motor Axons and Declining Muscle Grip Strength Following Mercury Vapor Inhalation in Mice. Inhal Toxicol 2008; 18:57-69. [PMID: 16326402 DOI: 10.1080/08958370500282902] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The effects of acute mercury vapor (Hg(0)) exposure on the peripheral motor system have not been previously addressed in the literature. Early case studies report that acute exposure in humans can cause symptoms resembling motor neuron disease (MND). Mercury granules can be histochemically demonstrated in the cytoplasm of murine motor neurons following Hg(0) exposure, suggesting it is transported from the neuromuscular junction (NMJ) to the cell body by retrograde axonal transport mechanisms. We considered the hypothesis that morphological damage to the peripheral motor axonal cytoskeleton possibly involving neurofilaments (NFs) follows Hg(0) exposure. Eight-week-old wild type (Wt) 129S/v mice were exposed to 500 microg/m(3) of Hg(0) for 4 h in an experimental vapor exposure chamber. Forelimb grip strength (FGS) was measured over 4-wk intervals prior to removal of the murine phrenic nerves (MPN) 7 mo postexposure. Autometallography of 7-microm-thick spinal-cord sections from Hg(0)-exposed mice confirmed the presence of mercury deposits in ventral horn motor neurons. The morphology of the myelinated motor axons was assessed by computer-assisted image analysis of 1-microm-thick resin cross sections of the MPN. The group exposed to Hg(0) showed a significant reduction in the mean axon caliber, p < .0001. Gaussian spectral analysis of axon diameter distribution showed atrophy principally to large myelinated fibers, a subpopulation of axons that is also affected in MND. This atrophic change was also accompanied by an increased irregularity in axon shape. FGS initially increased with age until 20 wk and then progressively decreased after 22 wk to 36 wk. In conclusion, Hg(0) exposure appears to reduce axon diameter, suggesting axon caliber-determining cytoskeletal components such as neurofilaments may be damaged by heavy metal-induced oxidative stress mechanisms, resulting in functional changes to motor units.
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Affiliation(s)
- Roger Stankovic
- Department of Pathology, University of Sydney, New South Wales, Australia.
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Barboni MTS, da Costa MF, Moura ALDA, Feitosa-Santana C, Gualtieri M, Lago M, Medrado-Faria MDA, Silveira LCDL, Ventura DF. Visual field losses in workers exposed to mercury vapor. ENVIRONMENTAL RESEARCH 2008; 107:124-31. [PMID: 17719027 DOI: 10.1016/j.envres.2007.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2007] [Revised: 04/29/2007] [Accepted: 07/09/2007] [Indexed: 05/16/2023]
Abstract
Visual field losses associated with mercury (Hg) exposure have only been assessed in patients exposed to methylmercury. Here we evaluate the automated visual field in 35 ex-workers (30 males; 44.20+/-5.92 years) occupationaly exposed to mercury vapor and 34 controls (21 males; 43.29+/-8.33 years). Visual fields were analyzed with the Humphrey Field Analyzer II (model 750i) using two tests: the standard automated perimetry (SAP, white-on-white) and the short wavelength automated perimetry (SWAP, blue-on-yellow) at 76 locations within a 27 degrees central visual field. Results were analyzed as the mean of the sensitivities measured at the fovea, and at five successive concentric rings, of increasing eccentricity, within the central field. Compared to controls, visual field sensitivities of the experimental group measured using SAP were lower for the fovea as well as for all five eccentricity rings (p<0.05). Sensitivities were significantly lower in the SWAP test (p<0.05) for four of the five extra-foveal eccentricity rings; they were not significant for the fovea (p=0.584) or for the 15 degrees eccentricity ring (p=0.965). These results suggest a widespread reduction of sensitivity in both visual field tests. Previous reports in the literature describe moderate to severe concentric constriction of the visual field in subjects with methylmercury intoxication measured manually with the Goldman perimeter. The present results amplify concerns regarding potential medical risks of exposure to environmental mercury sources by demonstrating significant and widespread reductions of visual sensitivity using the more reliable automated perimetry.
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Chuu JJ, Liu SH, Lin-Shiau SY. Differential neurotoxic effects of methylmercury and mercuric sulfide in rats. Toxicol Lett 2007; 169:109-20. [PMID: 17292570 DOI: 10.1016/j.toxlet.2006.12.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2006] [Revised: 12/20/2006] [Accepted: 12/20/2006] [Indexed: 10/23/2022]
Abstract
Methylmercury (MeHg) is an environmental toxicant, while mercuric sulfide (HgS) is a main active component of cinnabar, a Chinese mineral medicine used as a sedative. Because the neurotoxicological effects of HgS were not clearly understood, in this study, we attempted to compare HgS with MeHg in various physiological responses in Sprague-Dawley rats. After oral administration (2 mg/(kg day)) for consecutive 5 and 14 days, MeHg reversibly decreased both of motor nerve conduction velocity (MNCV) and tail flick response, whereas irreversibly inhibited all of the motor equilibrium performance, recovery of compound muscle action potentials (CMAP) following exhaustic tetanic stimuli and Na+/K+-ATPase activity of the isolated sciatic nerve. These toxic effects of MeHg were found in well correlation of Hg contents of various tissues (blood, cerebral cortex, liver and kidney) in rats. For comparison, a dose of 1g/(kg day) of HgS was orally administered to the rats based on our previous findings on ototoxicity of HgS. The results revealed that HgS only reversibly delayed the recovery of suppressed CMAP and inhibited sciatic nerve Na+/K+-ATPase activity in accordance to the lower Hg contents of the tissues. These findings provide the important information on the differential susceptibility of various nervous tissues to MeHg and HgS. The neruotoxic effects produced by HgS was estimated to be about 1000 of those induced by MeHg found in this study and our previous reports.
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Affiliation(s)
- Jiunn-Jye Chuu
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
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Shimada A, Nagayama Y, Morita T, Yoshida M, Suzuki JS, Satoh M, Tohyama C. Localization and role of metallothioneins in the olfactory pathway after exposure to mercury vapor. ACTA ACUST UNITED AC 2005; 57:117-25. [PMID: 16325522 DOI: 10.1016/j.etp.2005.08.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Accepted: 08/02/2005] [Indexed: 11/16/2022]
Abstract
We have investigated the localization and physiological roles of metallothioneins (MTs) in the olfactory pathway after exposure to mercury (Hg0) vapor. Male MT-null and wild-type mice were examined for the distribution of mercury, MT immunoreactivity and MT-III mRNA expression. There were no signs of histological changes in MT-null or wild-type mice. Light and electron microscopy of the samples stained with autometallography demonstrated chronological transfer of exposed mercury granules to the olfactory bulb by way of the olfactory tract. Basal expression of MT-I and -II immunoreactivity was observed in supporting cells, basal cells and acinar cells of the Bowman's gland of the olfactory mucosa in wild-type mice even without mercury exposure. In situ hybridization showed that signals for MT-III mRNA dominated in the olfactory cells of the olfactory mucosa, neurons in the olfactory bulb and those of brain in MT-null and wild-type mice. No difference in these findings was observed between samples taken at any interval after mercury exposure.
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Affiliation(s)
- A Shimada
- Department of Veterinary Pathology, Tottori University, Minami 4-101, Koyama, Tottori-shi, Tottori 680-0945, Japan.
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Morken TS, Sonnewald U, Aschner M, Syversen T. Effects of Methylmercury on Primary Brain Cells in Mono- and Co-culture. Toxicol Sci 2005; 87:169-75. [PMID: 15958655 DOI: 10.1093/toxsci/kfi227] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report on the uptake of MeHg in astrocytes and neurons, as well as specific indicators of neurotoxicity. Cerebellar granule neurons and astrocytes separately and in co-culture were cultured in the presence of MeHg and changes in 3-[4, 5-dimethylthiazol-2-yl]-2, 5 diphenyltetrazolium bromide (MTT)-reduction, lactate dehydrogenase (LDH) leakage, and cellular content of glutathione and amino acids were used as indicators of MeHg toxicity. Mitochondria in cortical astrocytes were slightly more sensitive than those in cerebellar astrocytes to the toxic effects of MeHg; furthermore, cellular integrity was better preserved in cerebellar astrocytes. When neurons and astrocytes from cerebellum were incubated in separable co-cultures using inserts, the astrocytes showed cellular damage at lower exposure to MeHg while neurons showed less changes compared to respective cell types in mono-cultures. Mercury uptake studies at 25 microM MeHg (10% serum present) showed that for neurons in co-culture the uptake was 1/3 compared to mono-cultures. In contrast, for astrocytes in co-culture, uptake was increased by 75%. A MeHg concentration-dependent increase of glutamate content in mono-cultures was noted. When MeHg concentration was increased to 10, 25, or 50 microM, neurons in co-cultures decreased their glutamate content, whereas astrocytes showed an increase. Other amino acids, such as glutamine, serine, valine, isoleucine, taurine, and phenylalanine were unaffected by MeHg. Glutathione content showed MeHg concentration-dependent changes in astrocytes and was increased in neurons in co-culture incubated with 5 microM MeHg. In conclusion, astrocytes appear to increase neuronal resistance, indicating a possible protective role for astrocytes in MeHg neurotoxicity.
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Affiliation(s)
- Tora Sund Morken
- Department of Neuroscience, Norwegian University of Science and Technology, N-7489 Trondheim, Norway.
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12
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Abstract
Female BALBc mice were administered HgCl2 at a single dose of 4 mg/kg i.p. The acute intoxication with Hg(II) salts (2 hr) caused accumulation of Hg(II) ions in the adrenal gland in general, and in the medulla, in particular. Based on data obtained with atomic absorption spectroscopy and quantitative cytochemistry, we determined the amount of mercury (II) in the adrenal glands and found it to be 14.2 ng Hg(II) (3.5 mg/kg wet weight of the adrenals). An uneven distribution of Hg(II) was found within the adrenal gland, not only between the medulla and cortex, but also within the cortex. The applied autometallographic method revealed that the cortex was negative except the zona glomerulosa, whereas the medulla showed a strong reaction localised to the chromaffin granules of the secretory cells. Both adrenaline and noradrenaline producing cells reacted. The comparison of the density of silver grains by scanning densitometry in the medulla and cortex revealed a significantly higher Hg(II) concentration in the medulla compared to the cortex (10 mg/kg vs 2 mg/kg, respectively). The results presented here suggest that there may be a connection between the symptoms of acute Hg(II) intoxication and its adrenal accumulation.
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Affiliation(s)
- László Kozma
- University Medical School, Department of Pathology, Debrecen, Hungary
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Vandenbulcke F, Grelle C, Fabre MC, Descamps M. Implication of the midgut of the centipede Lithobius forficatus in the heavy metal detoxification process. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 1998; 41:258-68. [PMID: 9799577 DOI: 10.1006/eesa.1998.1706] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Ultrastructural and autometallographic investigations of the midgut of experimentally intoxicated centipedes, Lithobius forficatus, have been performed to investigate the functional role of the epithelial cells in the detoxification of heavy metals. Ultrastructural study demonstrated that nonessential metals such as cadmium and lead may cause intracellular changes, i.e., appearance of electron-dense granules with a spongelike aspect and increase in the number and the size of concentrically structured granules. The autometallographic procedure demonstrated that both types of granules are the main organelles of the midgut to accumulate heavy metals. The permanent storage of metals in granules is a mechanism used by centipedes to reduce the toxic effects of heavy metals assimilated in excess. Consequently, midgut epithelium works as an efficient barrier to prevent excesses of certain metals in the internal environment.
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Affiliation(s)
- F Vandenbulcke
- Laboratoire de Biologie Animale, Université de Lille I, Villeneuve d'Ascq Cedex, F-59655, France
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14
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Abstract
With the experience accumulated from more than a century of silver applications in biology and medicine, physical development has become a powerful bioanalytical tool for marker amplification in blotting procedures, in situ hybridization, immunocytochemistry, histochemistry, and cytochemistry. Early, empirical techniques of silver impregnation followed by development in a reducing solution (chemical developer), or a solution which contained both silver reducers and silver salts (physical developer) were often capricious and suffered from unwanted silver precipitation caused by light and self-nucleation. To accommodate the modern demand for accurate physical development, various strategies have been devised to counter these problems. One approach has been to introduce organic colloids into the developer to keep the silver ions and reducer molecules apart, whilst excluding light by using a dark-room or by covering the solution. Albumen, gelatin, and complex polysaccharides have all been tested, but gum arabic is preferred. In addition, further control can be achieved by slowing down the rate of development with low pH and by changing from silver nitrate to silver lactate, which dissociates more slowly. Effective colloid protection in a physical developer is also provided by the inclusion of tungsten salts which can delay light-catalysed silver reduction and keep the developer clear for many minutes. The same result has been achieved by complexing the silver salt in the physical developer with very large organic molecules, restricting ionization. 'Light insensitive' commercial designer products have resulted. Probably no single formulation can satisfy all conditions of use, but with increased understanding of the mechanisms of physical developers a more flexible, user-friendly approach is anticipated.
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Affiliation(s)
- G R Newman
- Department of Pathology, University of Wales College of Medicine, Heath Park, Cardiff, UK
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15
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Abstract
Heavy metals have been implicated in the pathogenesis of sporadic motor neuron disease (MND). We were interested to see if inorganic mercury leads to oxidative damage in motor neurons since free radicals have been suspected to be involved in MND, so a method to examine oxidatively-damaged DNA in situ was used to examine individual motor neurons. Mice were exposed to 500 microg/m3 of mercury vapour for 2 h. Two, five, or ten days later sections from formalin-fixed, paraffin-embedded blocks of cervical spinal cord were incubated in avidin-FITC. Sections were examined under a fluorescence microscope and photographs of pairs of mercury-exposed and control spinal motor neurons were analysed semi-quantitatively for the amount of fluorescence using an image analysis program. Avidin fluorescence was seen in the perikaryon of both control and mercury-exposed motor neurons. In each control-mercury pair (four pairs per group) significantly more perikaryal fluorescence was seen in mercury-containing than in control motor neurons (Mann-Whitney testing). Mercury within the motor neuron perikaryon therefore leads to increased avidin binding, an indicator of oxidative damage to DNA. The findings support the hypothesis that an environmental toxin such as mercury can enter and damage motor neurons.
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Affiliation(s)
- R Pamphlett
- Department of Pathology, The University of Sydney, New South Wales, Australia.
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Ultrastructural and autometallographic studies of the nephrocytes of Lithobius forficatus L. (Myriapoda, Chilopoda): role in detoxification of cadmium and lead. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0020-7322(98)00034-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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17
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Martin MD, Williams BJ, Charleston JD, Oda D. Spontaneous exfoliation of teeth following severe elemental mercury poisoning: case report and histological investigation for mechanism. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 1997; 84:495-501. [PMID: 9394381 DOI: 10.1016/s1079-2104(97)90265-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Although the spontaneous exfoliation of teeth and breakdown of oral tissues from severe mercury intoxication have been noted for over a century, there are no published reports investigating the mechanisms of these phenomena. Severe mercury poisoning is rare in modern times, but it does occur. We present a case report and a histopathologic investigation into the mechanism of the associated tooth loss. METHODS An exfoliated tooth and periodontal and gingival tissues were obtained from a 15-month-old patient who had been severely intoxicated with elemental mercury over a period of months and hospitalized for severe neurologic and renal effects. The tissues were examined both by routine hematoxylin and eosin stain and by autometallography specific for mercury. For comparison, control tissue from an age-matched subject was examined with the autometallography technique. RESULTS Under light microscopy, the gingival tissue showed evidence of moderate to severe acute and chronic inflammation. The tooth pulp tissue showed evidence of moderate vascular dilatation and congestion, and it was infiltrated by many neutrophils. The autometallographic sections showed intense accumulations of mercury in the soft tissues of the mercury-exposed subject, but not in the tissues of the control subject. The deposits were primarily found in fibroblasts, which are essential to maintaining the integrity of the oral tissues. CONCLUSIONS Histopathologic and autometallographic examination of the affected tissue indicates that the primary mechanism of the spontaneous sloughing of tissue and loss of teeth may be the cytotoxic effects of the accumulation of mercury in fibroblasts. Studies of additional cases would be valuable to confirm this hypothesis.
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Affiliation(s)
- M D Martin
- Department of Oral Medicine, University of Washington School of Dentistry, Seattle, USA
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Møller-Madsen B. Localization of mercury in CNS of the rat. An autometallographic study. PHARMACOLOGY & TOXICOLOGY 1994; 75 Suppl 1:1-41. [PMID: 7937572 DOI: 10.1111/j.1600-0773.1994.tb01927.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Eide R, Schiönning JD, Bjugn R, Wesenberg GR, Fosse G. Autometallographic demonstration of mercury in rat molars. SCANDINAVIAN JOURNAL OF DENTAL RESEARCH 1994; 102:76-80. [PMID: 8153586 DOI: 10.1111/j.1600-0722.1994.tb01158.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Male, adult Wistar rats were exposed to 500 micrograms/m3 mercury vapor 6 h per day, 5 days a week for 4 wk. They were subsequently killed by transcardial perfusion. The molars were extracted, demineralized, and embedded in resin before sectioning. Autometallographic development was performed according to the method of Danscher & Möller-Madsen. Mercury deposits were found in small amounts in several areas of the pulp, but with larger accumulations of grains in relation to odontoblasts. Mercury also could be seen in odontoblastic processes in the dentin and predentin. Our conclusion is therefore that systemic uptake of mercury vapor leads to accumulation of mercury in the odontoblasts and that the mercury may be transported into the dentin tubules in the odontoblastic process.
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Affiliation(s)
- R Eide
- Department of Anatomy, University of Bergen, Norway
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Leyshon-Sørland K, Jasani B, Morgan AJ. The localization of mercury and metallothionein in the cerebellum of rats experimentally exposed to methylmercury. THE HISTOCHEMICAL JOURNAL 1994; 26:161-9. [PMID: 8150662 DOI: 10.1007/bf00157965] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Rats were dosed with methylmercuric chloride, either by gastric gavage (5 x 10 mg kg-1 body weight over a 15-day period), or in their drinking water (20 mg methylmercuric chloride l-1 for 14 or 42 days). Localization of mercury within the cerebellum was performed with a silver physical development technique, and metallothionein with dinitrophenyl hapten-sandwich immunohistochemistry. Mercury was detected in structurally undamaged Purkinje neurones and adjacent Bergmann glial cells; no mercury was detected in granule cells even though these small cells nearest the Purkinje layer had a high incidence of pyknotic nuclei. In general, metallothionein was detected mainly in Bergmann glial cells, Purkinje cells, astrocytes and glial cells of white matter; no metallothionein was detected in granule cells. We hypothesized that the resistance of Purkinje cells to methylmercuric chloride reflects their ability to transform organic mercurials to inorganic mercury that, in turn, induces the synthesis of radical-scavenging metallothionein molecules.
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Affiliation(s)
- K Leyshon-Sørland
- School of Pure and Applied Biology, University of Wales, College of Cardiff, UK
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Cavanagh JB, Nolan CC, Seville MP, Anderson VE, Leigh PN. Routes of excretion of neuronal lysosomal dense bodies after ventricular infusion of leupeptin in the rat: a study using ubiquitin and PGP 9.5 immunocytochemistry. JOURNAL OF NEUROCYTOLOGY 1993; 22:779-91. [PMID: 8270961 DOI: 10.1007/bf01181323] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
To determine the rate and routes of removal of lysosomal, lipofuscin-like dense bodies from neurons, the protease inhibitor, leupeptin, was infused into the lateral ventricle of rats for up to nine days. After seven days a number of animals were then allowed to recover. The formation and later disappearance of dense bodies was followed by morphology and immunocytochemistry. After 48 h of infusion lysosomal dense bodies in large numbers appeared in cortical, hippocampal and cerebellar neurons, which also showed increased ubiquitin immunoreactivity, as well as in other cell types. By 3-4 days ubiqutin-immunoreactive dense bodies were equally distributed between neurons and astroglia. After seven to nine days of infusion ubiquitin immunoreactive dense bodies filled neuronal perikarya, dendrites and expanded initial segments of many axons and were abundant in glial processes. All dense bodies studied by electron microscopy were ubiquitin immunoreactive. After four days of recovery dense bodies were markedly fewer in neuronal perikarya, and virtually all were now within glial processes. From 7 to 28 days of recovery, when most neurons appeared normal, lipofuscin bodies remained in axon initial segments and in reduced numbers in glial processes, particularly around blood vessels and beneath the pia of hippocampus and of cerebellar cortex. Thus, neurons probably have a steady passage of short lived proteins through the lysosomal excretory pathway. The observed temporal sequence of events on recovery suggests that secondary lysosomes probably pass rapidly from neuronal perikarya and dendrites to astrocytes and thus to the vascular bed or pia-arachnoid. The mechanism of cell-to-cell transfer is not clear from this study.
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Affiliation(s)
- J B Cavanagh
- Toxicology Unit, MRC Laboratories, Carshalton, Surrey, UK
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22
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Schiønning JD, Møller-Madsen B. Autometallographic detection of mercury in rat spinal cord after treatment with organic mercury. ACTA ACUST UNITED AC 1992; 61:307-13. [PMID: 1348892 DOI: 10.1007/bf02890432] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Autometallography was used to localize mercury in rat spinal cord after intraperitoneal administration of methylmercuric chloride (200 micrograms CH3HgCl daily). The technique permits small amounts of mercury sulfides and mercury selenides to be visualized by silver-enhancement. Mercury deposits were observed by light microscopy only in neurons. In all of the spinal cord segments selected (first cervical segment, C1; fifth cervical segment, C5; sixth thoracic segment, T6; and first lumbar segment, L1) the mercury was observed with cumulative dosages of 6000 micrograms CH3HgCl and greater. Laminae VII, VIII, and IX contained the majority of stained neurons, whereas laminae IV, V, VI, and X had a relatively lower density of mercury-containing neurons. Stained neurons were confined to specific cell groups, such as Clarke's column, nucleus intermedio-lateralis, nucleus cervicalis centralis, and nucleus dorsomedialis. At the ultrastructural level, mercury deposits were restricted to lysosomes of neurons and occasional accumulations in the lysosomes of ependymal cells.
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Affiliation(s)
- J D Schiønning
- Department of Neurobiology, University of Aarhus, Denmark
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Warfvinge K, Hua J, Berlin M. Mercury distribution in the rat brain after mercury vapor exposure. Toxicol Appl Pharmacol 1992; 117:46-52. [PMID: 1440612 DOI: 10.1016/0041-008x(92)90215-e] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Brown Norwegian rats were exposed to mercury vapor at a concentration of approximately 1 mg/m3 for 5 weeks 24 hr/day 7 days a week and 6 hr/day 3 days a week, respectively. The total mercury absorption was calculated to 264 and 35 micrograms per week and 100 g body weight. The mean blood mercury concentration was 0.25 +/- 0.03 and 0.09 +/- 0.01 microgram/g, and the total concentration in the brain was 5.03 +/- 0.73 and 0.71 +/- 0.10 microgram/g tissue, respectively. The mercury distribution in the brains was examined using a method based on chemographic principles. Mercury was found primarily in the neocortex, in the basal nuclei, and in the cerebellar Purkinje cells. This distribution pattern corresponded to the pattern of inorganic mercury described after exposure to methyl mercury. Distribution of mercury after administration of different mercury compounds is discussed.
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Affiliation(s)
- K Warfvinge
- Institute of Environmental Health, University of Lund, Sweden
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24
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Ernst E, Lauritsen JG. Effect of organic and inorganic mercury on human sperm motility. PHARMACOLOGY & TOXICOLOGY 1991; 68:440-4. [PMID: 1653954 DOI: 10.1111/j.1600-0773.1991.tb01267.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The effects of mercuric chloride and methyl mercuric chloride on the motility of human spermatozoa in vitro were investigated. Organic as well as inorganic mercury compounds decreased the percentage of motile spermatozoa. After 15 min. incubation with 40 microM mercuric chloride a significant decrease in sperm motility was observed. Less than 5% of spermatozoa were motile after 30 min. of exposure to 20 microM methyl mercuric chloride. These effects could not be attenuated by addition of 5 microM sodium selenite. The ultrastructural localization of mercury was demonstrated by autometallography. Silver-enhanced mercury deposits could be demonstrated only in spermatozoa exposed to inorganic mercury. In these cells mercury grains were most abundant in membranes of midpiece and tail.
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Affiliation(s)
- E Ernst
- Department of Neurobiology, University of Aarhus, Denmark
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25
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Schiønning J, Møller-Madsen B. Autometallographic mapping of mercury deposits in the spinal cord of rats treated with inorganic mercury. Acta Neuropathol 1991; 81:434-42. [PMID: 2028746 DOI: 10.1007/bf00293465] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The autometallographic method has been used in conjunction light and electron microscopy to determine the exact localization of mercury in the rat spinal cord. Adult male Wistar rats were treated intraperitoneally with accumulative doses of mercuric chloride (100-200 micrograms HgCl2 daily). Transverse sections of the first cervical segment (C1), fifth cervical segment (C5), sixth thoracic segment (T6), and first lumbar segment (L1) of the spinal cord were examined. The distribution pattern of mercury was dose dependent. In ventral horn motoneurons and neurons of nucleus dorso-medialis (C1) pronounced staining was found after a total dosage of 1200 micrograms HgCl2. In nucleus intermedio-lateralis (T6, L1) and nucleus cervicalis centralis (C1) stained neurons were first seen after 2600 micrograms HgCl2. Ultrastructurally, mercury deposits were exclusively located in lysosomes of neurons, astrocytes, endothelial cells, and ependymal cells.
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Affiliation(s)
- J Schiønning
- Department of Neurobiology, University of Aarhus, Denmark
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26
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Schiønning JD, Poulsen EH, Møller-Madsen B, Danscher G. Ultrastructural localization of mercury in rat dorsal root ganglia after exposure to mercury vapor. PROGRESS IN HISTOCHEMISTRY AND CYTOCHEMISTRY 1991; 23:249-55. [PMID: 1947148 DOI: 10.1016/s0079-6336(11)80192-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- J D Schiønning
- Department of Neurobiology, University of Aarhus, Denmark
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27
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Arvidson B, Arvidsson J. Retrograde axonal transport of mercury in primary sensory neurons innervating the tooth pulp in the rat. Neurosci Lett 1990; 115:29-32. [PMID: 1699174 DOI: 10.1016/0304-3940(90)90512-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The pulp cavity of the first upper molar was exposed unilaterally in adult rats with a dental drill and about 1 microliter of mercuric chloride was injected into the coronal pulp. The rats were killed after 1-24 days and frozen sections from the trigeminal ganglia were subjected to silver acetate autometallography for demonstration of mercury. Mercury was found to have accumulated in neurons of the ipsilateral trigeminal ganglion by retrograde axonal transport. The possible implications of this finding are discussed.
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Affiliation(s)
- B Arvidson
- Department of Neurology, University Hospital, Uppsala, Sweden
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28
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Doerr-Schott J, Kitamoto T, Tateishi J, Boellaard JW, Heldt N, Lichte C. Immunogold light and electron microscopic detection of amyloid plaques in transmissible spongiform encephalopathies. Neuropathol Appl Neurobiol 1990; 16:85-9. [PMID: 2181333 DOI: 10.1111/j.1365-2990.1990.tb00934.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The antigenicity of the 'prion' protein amyloid fibrils was shown to be preserved after glutaraldehyde/OsO4 fixation in uranyl acetate-stained brain tissue blocks from patients with Gerstmann-Sträussler syndrome (GSS) and from mice infected with Creutzfeldt-Jakob disease (CJD). Amyloid plaques were demonstrated by light microscopy in immunogold silver-intensified semithin sections. Under the electron microscope, the amyloid fibrils were labelled in immunogold-reacted ultrathin sections using an antiserum prepared against GSS amyloid plaque cores and mouse amyloid fibrils respectively. The influence of various oxidizing agents (hydrogen peroxide, sodium metaperiodate) on the tissue preservation and the immunohistochemical detection was tested.
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Affiliation(s)
- J Doerr-Schott
- Centre de Neurochimie, Université Louis Pasteur, Strasbourg, France
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29
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Baatrup E, Thorlacius-Ussing O, Nielsen HL, Wilsky K. Mercury-selenium interactions in relation to histochemical staining of mercury in the rat liver. THE HISTOCHEMICAL JOURNAL 1989; 21:89-98. [PMID: 2469670 DOI: 10.1007/bf01005984] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Selenium has been suggested to enhance the histochemical staining of mercury when sections of tissue are subjected to the silver-enhancement method. In the present study, histochemical staining patterns of mercury in tissue sections of rat livers were compared with the actual content of organic and inorganic Hg in the livers, in both the presence and the absence of Se. Rats were injected intravenously with 5 micrograms of Hg g-1 body weight as methyl [203Hg] mercury chloride (MeHg) or as [203Hg]mercuric chloride (Hg2+). After 2 h, half the rats received an additional intraperitoneal injection of 2 micrograms of Se g-1 body weight as sodium [75Se]selenite. All the rats were killed 1 h later. Homogenized liver samples were prepared for mercury analysis by two different methods: alkaline digestion and ultrasonic disintegration. Quantitative chemical analysis based on benzene extraction of the radioactively labelled Hg compounds showed that the chemical form of mercury, either organic or inorganic, was preserved from its administration to its deposition in the liver. Light and electron microscopy demonstrated that no silver enhancement of Hg occurred when MeHg alone was present in the sections of tissue, whereas MeHg accompanied by Se induced a moderate deposition of silver grains. In contrast, sections containing Hg2+ alone yielded some staining, and the addition of Se increased the staining dramatically. The results of the present study show that acute selenite pretreatment is a prerequisite for the histochemical demonstration of methyl mercury, and greatly increases the staining of inorganic mercury when applying the silver-enhancement method.
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Affiliation(s)
- E Baatrup
- Institute of Zoology, University of Aarhus, Denmark
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30
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Hargreaves RJ, Evans JG, Janota I, Magos L, Cavanagh JB. Persistent mercury in nerve cells 16 years after metallic mercury poisoning. Neuropathol Appl Neurobiol 1988; 14:443-52. [PMID: 3226504 DOI: 10.1111/j.1365-2990.1988.tb01336.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A male subject, after exposure to mercury metal at work in 1968, developed classical signs of mercurialism from which he made a slow clinical recovery. He subsequently developed psychoneurotic symptoms and became an alcoholic; he never returned to work and died in 1984. No histological changes relevant to mercury intoxication were found in the brain, but staining by Danscher & Schroeder's method for mercury showed many positively staining lysosomal dense bodies in a large proportion of nerve cells, and the presence of mercury was confirmed by elemental X-ray analysis. The mercury content of the brain was increased, much of it being present in colloidal form.
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31
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Arimura K, Murai Y, Rosales RL, Izumo S. Spinal roots of rats poisoned with methylmercury: physiology and pathology. Muscle Nerve 1988; 11:762-8. [PMID: 3405242 DOI: 10.1002/mus.880110713] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The evoked potentials in the ventral and dorsal roots were recorded independently by stimulating the sciatic nerve of both control and methylmercury-poisoned rats. Poisoned rats showed markedly decreased amplitudes but normal latencies of the potentials evoked in the dorsal roots. Potentials evoked in the ventral roots had normal latencies and amplitudes. Pathological correlates indicated acute axonal degeneration of the dorsal roots, with a significant decrease of the large and small myelinated fiber densities. The ventral roots were histologically unremarkable. Our pathological confirmation of the electrophysiologic changes in the methylmercury-poisoned rats enables us to substantially assess the pathophysiological aspects of acute lesions in the spinal roots.
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Affiliation(s)
- K Arimura
- Third Department of Internal Medicine, Faculty of Medicine, Kagoshima University, Japan
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32
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Sparrow S, Magos L, Snowden R. The effect of sodium chromate pretreatment on mercuric chloride-induced nephrotoxicity. Arch Toxicol 1988; 61:440-3. [PMID: 3190441 DOI: 10.1007/bf00293689] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Sodium chromate (20 mg/kg, s.c.), which in male rats inflicted necrotic damage mainly in the P1 region (proximal part of the proximal convoluted tubules), protected against proximal tubular necrosis induced by 0.5 or 3.0 mg Hg2+/kg in the P2 (distal part of the proximal convoluted tubules) and P3 (pars recta part of the proximal tubules) regions. Histochemical staining for mercury indicated that chromate increased mercury deposition in those cells of the P1 region which were unaffected by chromate (had intact brush border) but did not decrease mercury deposition in the most severely affected P3 region. Chromate pretreatment actually increased mercury deposition in the kidneys of animals killed 24 h after the injection of 0.5 mg Hg2+. The protective effect was mutual. Cellular proliferation and fibrosis observed 4-5 days after chromate were prevented by injecting 0.5 mg Hg2+/kg 3 days after chromate treatment.
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Affiliation(s)
- S Sparrow
- Life Science Research, Elm Farm Laboratories Occold, Nr. Eye, Suffolk, United Kingdom
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33
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Neiss WF. Enhancement of the periodic acid--Schiff (PAS) and periodic acid--thiocarbohydrazide--silver proteinate (PA-TCH-SP) reaction in LR white sections. HISTOCHEMISTRY 1988; 88:603-12. [PMID: 2835340 DOI: 10.1007/bf00570331] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
LR White is a well-suited resin for the demonstration of carbohydrates with the PAS or PA-TCH-SP reaction in semithin and ultrathin sections. The intensity of these reactions can be greatly enhanced by using 3 steps in tissue preparation, either singly or in combination: 1) The PAS reaction in semithin sections turns out stronger after partial (70% ethanol) than complete (100% ethanol) dehydration of the tissue before its transfer to 100% LR White. 2) Silver enhancement of the PA-TCH-SP reaction product can simply be effected by physical development of ultrathin sections (PA-TCH-SP-SE reaction). Least precipitates are formed in this procedure, when sections are mounted on uncoated gold grids, processed for cytochemistry, and thinly coated with carbon in the end. 3) The use of hot silver proteinate (50 degrees C) plus strong silver enhancement (15-20 min silver lactate developer) reveals minute concentrations of TCH-labelled aldehyde groups in the tissue that do not react with silver proteinate at room temperature.--Silver enhancement and the use of hot silver proteinate do not depend on LR White, but may also be applied to ultrathin sections of tissue embedded in other resins.
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Affiliation(s)
- W F Neiss
- Anatomisches Institut, Universität Würzburg, Federal Republic of Germany
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34
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Christensen M, Mogensen SC, Rungby J. Toxicity and ultrastructural localization of mercuric chloride in cultured murine macrophages. Arch Toxicol 1988; 62:440-6. [PMID: 3250374 DOI: 10.1007/bf00288347] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The effects of mercuric chloride on cell survival, phagocytosis and cell migration were examined in cultured mouse peritoneal macrophages, and the accumulation of mercuric chloride in the cells was visualized by autometallography and evaluated by light and electron microscopy. Macrophages exposed to mercury concentrations from 1.25 microM to 10 microM mercuric chloride showed a concentration- and time-dependent increase in mercuric chloride accumulation, while cells exposed to 20 microM and 40 microM mercury showed an inverse relationship between mercury concentration and the accumulation of mercury. Mercury concentrations above these levels caused cell necrosis. Electron microscopy revealed that mercury was located primarily within lysosomes but also in the nucleus and cytoplasm. Mercury increased the death rate of macrophages in a concentration-dependent manner when cells were treated with mercury concentrations not causing cell necrosis. Further, we found that mercury clearly impaired macrophage random migration and possibly the capability for phagocytosis.
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Affiliation(s)
- M Christensen
- Department of Neurobiology, Institute of Anatomy, Aarhus C, Denmark
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35
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Marchetti A, Bistocchi M, Tognetti AR. Silver enhancement of protein A-gold probes on resin-embedded ultrathin sections. An electron microscopic localization of mouse mammary tumor virus (MMTV) antigens. HISTOCHEMISTRY 1987; 86:371-3. [PMID: 2437083 DOI: 10.1007/bf00494995] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A simple method is described allowing the enhancement of the visibility of small gold probes for the electron microscopy. This method, which allows the silver intensification of gold directly on epon-embedded ultrathin sections, was used for the electron microscopic localization of Mouse Mammary Tumor Virus (MMTV) antigens in cultured cells derived from GR and BALB/cfRIII mouse mammary tumors. After the immunostaining with the preembedding protein A-gold technique, the ultrathin sections, placed on 200 mesh copper grids, were rehydrated and exposed to a photographic developer containing silver nitrate. During this physical development gold particles are incapsulated in growing shells of metallic silver, which gradually become more and more visible. We were able to obtain a heavy labelling of the viral particles, well visible even at low magnification, with a negligeable background staining. The present technique can be useful whenever it is necessary to use the smallest gold probes today available.
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36
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Thorlacius-Ussing O, Møller Graabaek P. Simultaneous ultrastructural demonstration of heavy metals (silver, mercury) and acid phosphatase. THE HISTOCHEMICAL JOURNAL 1986; 18:639-46. [PMID: 3558002 DOI: 10.1007/bf01675299] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A histochemical technique which permits the simultaneous visualization of heavy metals and acid phosphatase at the ultrastructural level is described. The technique was applied to the anterior pituitary gland, the spinal cord and the liver. In all of the tested organs, both mercury and silver were found to accumulate primarily in the lysosomes, although small amounts of both metals could be observed in other organelles including endocytotic vesicles. In the anterior pituitary, few mercury deposits were found in the secretory granules.
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37
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Rungby J. Exogenous silver in dorsal root ganglia, peripheral nerve, enteric ganglia, and adrenal medulla. Acta Neuropathol 1986; 69:45-53. [PMID: 3962597 DOI: 10.1007/bf00687038] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Following intraperitoneal (i.p.) or oral administration of silver salts, the anatomic distribution of silver in the peripheral nervous system (PNS) has been studied. The structures examined were dorsal root ganglia, peripheral nerve (N. ischiadicus), enteric ganglia, and adrenal medulla. Four days after an i.p. injection of silver lactate, silver deposits were found in these structures. The silver content remained stable during the observation period (45 days). The localization of silver deposits in the orally treated animals was independent of the administered silver salt (silver nitrate or silver lactate). The silver deposits in neurons and chromaffin cells were located in the cytoplasm. In all organs silver was present in large amounts in connective tissue membranes, macrophage-like cells, vascular basal laminae, and supporting cells. Satellite cells of the dorsal root ganglia were always heavily stained, while less stain was present in Schwann cells of the peripheral nerves. Intracellular deposits were invariably located in lysosomes, whereas extracellular grains were found in connective tissue fibers and basement membranes.
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38
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Hultman P, Eneström S, Schenck H. Renal handling of inorganic mercury in mice. ACTA ACUST UNITED AC 1985. [DOI: 10.1007/bf02912098] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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39
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Magos L, Brown AW, Sparrow S, Bailey E, Snowden RT, Skipp WR. The comparative toxicology of ethyl- and methylmercury. Arch Toxicol 1985; 57:260-7. [PMID: 4091651 DOI: 10.1007/bf00324789] [Citation(s) in RCA: 132] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Neurotoxicity and renotoxicity were compared in rats given by gastric gavage five daily doses of 8.0 mg Hg/kg methyl- or ethylmercuric chloride or 9.6 mg Hg/kg ethylmercuric chloride. Three or 10 days after the last treatment day rats treated with either 8.0 or 9.6 mg Hg/kg ethylmercury had higher total or organic mercury concentrations in blood and lower concentrations in kidneys and brain than methylmercury-treated rats. In each of these tissues the inorganic mercury concentration was higher after ethyl- than after methylmercury. Weight loss relative to the expected body weight and renal damage was higher in ethylmercury-treated rats than in rats given equimolar doses of methylmercury. These effects became more severe when the dose of ethylmercury was increased by 20%. Thus in renotoxicity the renal concentration of inorganic mercury seems to be more important than the concentration of organic or total mercury. In methylmercury-treated rats damage and inorganic mercury deposits were restricted to the P2 region of the proximal tubules, while in ethylmercury-treated rats the distribution of mercury and damage was more widespread. There was little difference in the neurotoxicities of methylmercury and ethylmercury when effects on the dorsal root ganglia or coordination disorders were compared. Based on both criteria, an equimolar dose of ethylmercury was less neurotoxic than methylmercury, but a 20% increase in the dose of ethylmercury was enough to raise the sum of coordination disorder scores slightly and ganglion damage significantly above those in methylmercury-treated rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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40
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Hargreaves RJ, Foster JR, Pelling D, Moorhouse SR, Gangolli SD, Rowland IR. Changes in the distribution of histochemically localized mercury in the CNS and in tissue levels of organic and inorganic mercury during the development of intoxication in methylmercury treated rats. Neuropathol Appl Neurobiol 1985; 11:383-401. [PMID: 4080088 DOI: 10.1111/j.1365-2990.1985.tb00034.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The development of neurotoxicity in rats after exposure to methylmercuric chloride was monitored using behavioural indices. At selected time points the cellular localization of mercury and the relative amounts of organic and inorganic mercury were determined in several regions of the CNS, and in some non-neural tissues. The CNS showed an affinity for organic mercury, the levels of inorganic mercury remaining low throughout symptomatic intoxication. Histopathological changes were not closely related to the regional tissue content of the organic or inorganic forms, nor to mercury localized histochemically at the cellular level. The stained deposits, which had focal cytoplasmic distribution, appeared in glial cells initially then in larger neurones as the intoxication progressed. These observations may represent changes in the mercury content of different cell types or reflect differences in the way that they handle a similar burden of mercury. A transitory accumulation of mercury in glial cells may be a factor contributing to the occurrence of a latent period and sequestration of mercury in cytoplasmic organelles may serve to protect some cell types from injury.
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41
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Møller-Madsen B, Simonsen OH, Doss DN, Danscher G. Gold in the ovary of rats exposed to sodium aurothiomalate. Exp Mol Pathol 1985; 42:287-92. [PMID: 3920071 DOI: 10.1016/0014-4800(85)90035-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The ultrastructural localization of gold in the ovary of rats injected intraperitoneally with sodium aurothiomalate has been demonstrated using a histochemical technique that visualizes minute traces of gold. Gold was visualized in the oocyte within the cortical granules and in lysosomes of theca interna cells and interstitial cells.
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42
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Thorlacius-Ussing O, Møller-Madsen B, Danscher G. Intracellular accumulation of mercury in the anterior pituitary of rats exposed to mercuric chloride. Exp Mol Pathol 1985; 42:278-86. [PMID: 3979523 DOI: 10.1016/0014-4800(85)90034-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A histochemical technique has been used to reveal mercury deposits by light and electron microscopy in the anterior pituitary of adult rats. After administration of mercuric chloride either in the drinking water or by intraperitoneal injection, deposits were found within lysosomes and secretory granules in somatotrophs, thyrotrophs, follicular cells, and marginal cells. The amount of mercury deposited was proportional to the dose of mercuric chloride given. Significantly more mercury was found in rats given intraperitoneal injections compared to those intoxicated with mercuric chloride in the drinking water. Mercury was retained in the cells for at least 4 months after the last injection although the amount of deposits decreased in this period.
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43
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Scopsi L, Larsson LI. Increased sensitivity in immunocytochemistry. Effects of double application of antibodies and of silver intensification on immunogold and peroxidase-antiperoxidase staining techniques. HISTOCHEMISTRY 1985; 82:321-9. [PMID: 2409059 DOI: 10.1007/bf00494060] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sensitivity and detection efficiency of immunocytochemical methods were tested on cytochemical models and tissue material, respectively. Use of silver intensification procedures revealed that staining with immunogold reagents could be rendered equally or even more sensitive than the standard peroxidase-antiperoxidase (PAP) method. Further increases in sensitivity with both methods could be obtained by double application of the primary antiserum. Combined use of the immunogold techniques and the PAP method with development in diaminobenzidine and subsequent silver intensification resulted in the most sensitive procedures. The procedures were applied to a wide variety of tissue preparations, including whole mount preparations of the external longitudinal muscle layer of the gut wall and were found not to produce any unspecific staining in any tissue tested. Use of immunogold-silver and, particularly of the combined immunogold-silver-PAP methods may be valuable for analyzing tissues and tumours containing small amounts of antigen, for testing the quality of immunogold staining procedures intended for ultrastructural studies and for electroblotting techniques.
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44
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Eneström S, Hultman P. Immune-mediated glomerulonephritis induced by mercuric chloride in mice. EXPERIENTIA 1984; 40:1234-40. [PMID: 6500008 DOI: 10.1007/bf01946653] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The BALB/c mouse developed mesangial deposits of immune constituents and light microscopical changes characteristic of immune complex glomerulonephritis after 8 weeks' treatment with mercuric chloride given by s.c. injection. There were no signs of linear of granular immune deposits along the glomerular capillary basement membrane after 2 or 8 weeks. The antigen could not be identified. No antibodies to nuclear or renal structures were found. Using a histochemical method (silver amplification) mercury was detected by light and electron microscopy in tubular and glomerular structures. Mercury was present in secondary lysosomes of the mesangial cells after eight weeks of mercury poisoning.
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45
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Thorlacius-Ussing O, Rungby J. Ultrastructural localization of exogenous silver in the anterior pituitary gland of the rat. Exp Mol Pathol 1984; 41:58-66. [PMID: 6468636 DOI: 10.1016/0014-4800(84)90007-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Silver accumulations in the anterior pituitary of argyric rats were demonstrated using a histochemical method that visualizes minute traces of the metal. Silver was localized intra- and extracellularly throughout the anterior pituitary. Intracellular deposits were found within the lysosomes of somatotrophs and gonadotrophs. Extracellularly, the grains were located in basal laminae of portal veins and sinusoidal capillaries and in the membrane separating the anterior pituitary and part intermedia. The amount of deposited silver was dependent upon the dose of silver administered. Increasing the dose of silver lactate from 10 to 30 mg resulted in increased deposition, whereas a further increase to 60 mg did not alter the amount of silver deposited.
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46
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Møller-Madsen B, Thorlacius-Ussing O. Localization of gold in the anterior pituitary gland of rats exposed to sodium aurothiomalate. Exp Mol Pathol 1984; 41:74-80. [PMID: 6432575 DOI: 10.1016/0014-4800(84)90009-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The ultrastructural localization of gold in the anterior pituitary of rats injected intraperitoneally with sodium aurothiomalate has been demonstrated using a histochemical technique that visualizes minute traces of gold. Gold was located intracellularly within lysosome-like bodies of marginal layer cells, follicular cells, and thyrotrophs. Gold was not seen within secretion granules. The possible mechanism by which gold is taken up into the cells is discussed.
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47
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Møller-Madsen B, Mogensen SC, Danscher G. Ultrastructural localization of gold in macrophages and mast cells exposed to aurothioglucose. Exp Mol Pathol 1984; 40:148-54. [PMID: 6420183 DOI: 10.1016/0014-4800(84)90072-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The ultrastructural localization of gold in resting, stimulated, and activated mouse peritoneal cells exposed in vivo and in vitro to aurothioglucose was examined by a photochemical technique. Activated macrophages from herpes simplex virus type 2 infected mice showed the heaviest accumulation of gold, located in phagolysosomes. Gold was also visualized in granules of mast cells and in nuclei of disintegrated cells. No gold was found in polymorphonuclear leucocytes and in lymphocytes. The mechanism by which gold is taken up into the cells is discussed.
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Choi BH. Cellular and subcellular demonstration of mercury in situ by modified sulfide-silver technique and photoemulsion histochemistry. Exp Mol Pathol 1984; 40:109-21. [PMID: 6692899 DOI: 10.1016/0014-4800(84)90069-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Young adult C57BL/6J mice were injected with 4.0 mg/kg body wt of methylmercuric chloride (MMC) for 3 consecutive days for a total of 12.0 mg/kg. Control animals received physiological saline in place of MMC. One week following the last injection, the animals were sacrificed. Representative tissue blocks and sections from the brain, kidney, and liver were subjected to a modified sulfide-silver technique (SST) and the photoemulsion histochemical method. The results show that both of these techniques demonstrate consistent and distinct localization of mercury (Hg) gains in cells and subcellular organelles. These methods are based on the principle that Hg compounds react strongly with sulfhydryl groups in tissues and cells to form Hg-sulfides and also on the affinity of Hg and silver to form an amalgam when placed in a physical developer or photographic emulsion. Thus Hg in cells is demonstrable without prior treatment of sulfide solution. The methods are simple and reliable when used with proper controls. Specific localization of Hg in cells in situ without the use of radioactive material and without disruption of anatomical relationships provided by these methods offers distinct advantages over other methods of Hg determination. Thus it would be possible to conduct a retrospective or prospective study of human autopsy materials and also would allow direct correlation of Hg deposition with pathological changes in cells and subcellular organelles.
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Carmignani M, Boscolo P. Cardiovascular homeostasis in rats chronically exposed to mercuric chloride. ARCHIVES OF TOXICOLOGY. SUPPLEMENT. = ARCHIV FUR TOXIKOLOGIE. SUPPLEMENT 1984; 7:383-8. [PMID: 6596006 DOI: 10.1007/978-3-642-69132-4_66] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Two groups of male Sprague-Dawley rats received from weaning 50 micrograms/ml of mercury as mercuric chloride (HgCl2) in drinking water for 320 and 350 days. Hg exposure increased cardiac inotropism, without chronotropic changes, in both groups, and induced arterial hypertension in the rats exposed for 350 days. In the exposed rats, cardiovascular responses to the stimulation of peripheral alpha and beta adrenoceptors were decreased and increased, respectively, possibly through a reduced intracellular availability of calcium ions for contractile mechanisms. Hg exposure did not affect either vagal or sympathetic activity or cardiovascular reactivity to several physiological agonists. On the other hand, Hg exposure induced baroreflex hyposensitivity and produced a drastic alteration of the levels of copper and zinc in brain and kidney.
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Møller-Madsen B, Danscher G. Transplacental transport of gold in rats exposed to sodium aurothiomalate. Exp Mol Pathol 1983; 39:327-31. [PMID: 6416891 DOI: 10.1016/0014-4800(83)90061-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The ultrastructural localization of gold in yolk sacs and fetuses from rats exposed to sodium aurothiomalate (Myocrisin, 25 mg/kg intraperitoneally) was examined by a photochemical technique. Gold was found in epithelial cells of the yolk sac and in hepatocytes of the fetuses. Ultrastructurally, gold was located in lysosome-like bodies. Gold was not detected in the kidney or the central nervous system of the fetuses. Maternal liver and kidney were included as controls for efficacy of gold treatment.
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