Distribution of bismuth in the brain after intraperitoneal dosing of bismuth subnitrate in mice: Implications for routes of entry of xenobiotic metals into the brain

Ross, Joseph F.; Switzer, Robert C.; Poston, Michael R.; Lawhorn, Gerald T.

doi:10.1016/0006-8993(96)00146-1

Cited by 51 publications

(24 citation statements)

References 49 publications

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“…Spinal cords were embedded in a gelatin matrix using MultiCord Technology (NeuroScience Associates) as used in previous studies. 8,19 The block of embedded spinal cord was allowed to cure and was then rapidly frozen by immersion in isopentane chilled with crushed dry ice. The block was mounted on a freezing stage of an AO 860 sliding microtome and sectioned in the coronal and sagittal plane at 40 μm.…”

Section: Embedding and Sectioningmentioning

confidence: 99%

Microsurgical anatomy of the arterial basket of the conus medullaris

Martirosyan

Kalani

Lemole

et al. 2015

SPI

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OBJECT The arterial basket of the conus medullaris (ABCM) consists of 1 or 2 arteries arising from the anterior spinal artery (ASA) and circumferentially connecting the ASA and the posterior spinal arteries (PSAs). The arterial basket can be involved in arteriovenous fistulas and arteriovenous malformations of the conus. In this article, the authors describe the microsurgical anatomy of the ABCM with emphasis on its morphometric parameters and important role in the intrinsic blood supply of the conus medullaris. METHODS The authors performed microsurgical dissections on 16 formalin-fixed human spinal cords harvested within 24 hours of death. The course, diameter, and branching angles of the arteries comprising the ABCM were then identified and measured. In addition, histological sections were obtained to identify perforating vessels arising from the ABCM. RESULTS The ASA tapers as it nears the conus medullaris (mean preconus diameter 0.7 ± 0.12 mm vs mean conus diameter 0.38 ± 0.08 mm). The ASA forms an anastomotic basket with the posterior spinal artery (PSA) via anastomotic branches. In most of the specimens (n= 13, 81.3%), bilateral arteries formed connections between the ASA and PSA. However, in the remaining specimens (n= 3, 18.7%), a unilateral right-sided anastomotic artery was identified. The mean diameter of the right ABCM branch was 0.49 ± 0.13 mm, and the mean diameter of the left branch was 0.53 ± 0.14 mm. The mean branching angles of the arteries forming the anastomotic basket were 95.9° ± 36.6° and 90° ± 34.3° for the right- and left-sided arteries, respectively. In cases of bilateral arterial anastomoses between the ASA and PSA, the mean distance between the origins of the arteries was 4.5 ± 3.3 mm. Histological analysis revealed numerous perforating vessels supplying tissue of the conus medullaris. CONCLUSIONS The ABCM is a critical anastomotic connection between the ASA and PSA, which play an important role in the intrinsic blood supply of the conus medullaris. The ABCM provides an important compensatory function in the blood supply of the spinal cord. Its involvement in conus medullaris vascular malformations makes it a critical anatomical structure.

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Section: Embedding and Sectioningmentioning

confidence: 99%

Microsurgical anatomy of the arterial basket of the conus medullaris

Martirosyan

Kalani

Lemole

et al. 2015

SPI

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“…It may be an important species for bismuth transport from the liver to the kidney and be involved in bismuth storage in the kidney. In addition, the neurotoxicity of bismuth drugs (encephalopathy) could be related to the binding of Bi 3ϩ to the brain-specific metallothionein(III), since the distribution of Bi 3ϩ in mouse brain is very similar to that of Cu ϩ and Ag ϩ (27 ) by Bi 3ϩ was much faster than from the ␣-domain. These differences between the structure and reactivity of bismuth metallothionein compared with zinc metallothionein are likely to have implications for its biological properties.…”

Section: X-ray Spectroscopy-xanes and Exafs Measurementsmentioning

confidence: 99%

Interactions of Bismuth Complexes with Metallothionein(II)

Sun

Harvey

et al. 1999

Journal of Biological Chemistry

151

122

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. Metallothionein (MT)1 is an intriguing, low molecular mass (ϳ7 kDa), cysteine-and metal-rich protein. It was first isolated from equine renal cortex 40 years ago (1) and contains 61 amino acids, of which 20 are cysteine residues. Since then, similar proteins have been isolated from the kidney, liver, and intestines of a variety of animal species (2), fungi (3, 4), plants (5), and metal-resistant bacteria (6 -8). The two major isoforms of mammalian MT (MT(I) and MT(II)) differ only in minor sequence changes and overall charge. Recently, the discovery of a growth inhibitory factor (GIF) from human brain tissue and nerve and its characterization as a metallothionein (MT-III) has stimulated new interests in studying this small protein (9, 10).The functions of metallothionein are still not fully understood. It appears to play a fundamental role in the metabolism of copper and zinc ions under various physiological conditions (11, 12), including its ability to donate metal ions to apo-Zn 2ϩ enzymes (13,14 (18,19), thereby preventing reactions with other cellular targets in mammals and other higher organisms (20). Metallothionein also appears to play a role in radical scavenging, stress response, and the pharmacology of metallodrugs and alkylating agents (12,21,22).The best characterized mammalian metallothioneins contain a single polypeptide chain with seven bound metal ions (either Zn 2ϩ or Cd 2ϩ ). The x-ray crystal structure of rat liver Zn 2 Cd 5 -MT(II) (23) and NMR solution structures of rabbit liver Cd 7 -MT(II) (24), rat liver Cd 7 -MT(II) (25), and human liver Cd 7 -MT (26) show that metallothionein contains two structurally independent ␣ (C-terminal) and ␤ (N-terminal) domains, which are linked in the protein via two amino acids. The seven metal ions are present in clusters of four and three metals bound to bridging and terminal cysteine thiolate ligands, with metal-tothiolate ratios of M 4 S 11 and M 3 S 9 for the ␣-and ␤-domains, respectively (23). When both Zn 2ϩ and Cd 2ϩ are present, Cd 2ϩ binds preferentially to the ␣-domain, whereas Zn 2ϩ is found preferentially in the ␤-domain (23, 28). A Zn 2 Cd three-metal cluster (␤ domain) in MT has the same structure as a Cd 3 cluster (23). The ␣-domain binds Cd 2ϩ ions cooperatively (29). All 20-cysteine residues participate in metal binding, and each of the seven Zn 2ϩ or Cd 2ϩ ions is tetrahedrally coordinated to four cysteine thiolate sulfur atoms (30,31).Bismuth is known to induce the synthesis of renal metallothionein (32), and it has been shown that pretreatment with bismuth complexes can prevent the toxic side effects of the anti-cancer drug cisplatin without compromising its anti-tumor activity (33)(34)(35)(36)

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“…The invisible picture was then made visible by being developed in a "physical developer," a misleading name based on the misconception that the silver amplification performed under these circumstances was different from the normal "chemical development" (Danscher 1996). Since Timm's introduction of the concept that some metal sulfide accumulations could be silver-enhanced by physical development (Timm 1958(Timm ,1962) many scientists have used his approach, have tried to improve the technique, and have added new metals to the family of nanocrystals that can be silver-enhanced (e.g., Haug 1967Haug ,1973Haug ,1974Brunk and Brun 1972;Danscher 1981a,b;Sloviter 1990;Danscher and Møller-Madsen 1985;Zdolsek et al 1993;Ross et al 1996). Danscher, Stoltenberg, Bruhn, Søndergaard, Jensen In the early 1980s, Timm's original sulfide silver method was made zinc-specific (Danscher 1981c), and the selenium technique for in vivo creation of zinc-selenium nanocrystals in zinc-enriched (ZEN) neuronal terminals and for retrograde axonal tracing of ZEN neurons was introduced (Danscher 1982(Danscher ,1984aHowell and Frederickson 1990).…”

mentioning

confidence: 99%

Immersion Autometallography: Histochemical In Situ Capturing of Zinc Ions in Catalytic Zinc-Sulfur Nanocrystals

Danscher

Stoltenberg

Bruhn

et al. 2004

J Histochem Cytochem.

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S U M M A R YIn the mid-1980s, two versions of Timm's original immersion sulfide silver method were published. The authors used immersion of tissue in a sulfide solution as opposed to Timm, who used immersion of tissue blocks in hydrogen sulfide-bubbled alcohol. The autometallography staining resulting from the "sulfide only immersion" was not particularly impressive, but the significance of this return to an old approach became obvious when Wenzel and co-workers presented their approach in connection with introduction by the Palmiter group of zinc transporter 3 (ZnT3). The Wenzel/Palmiter pictures are the first high-resolution, high-quality pictures taken from tissues in which free and loosely bound zinc ions have been captured in zinc-sulfur nanocrystals by immersion. The trick was to place formalin-fixed blocks of mouse brains in a solution containing 3% glutaraldehyde and 0.1% sodium sulfide, ingredients used for transcardial perfusion in the zinc-specific NeoTimm method. That the NeoTimm technique results in silver enhancement of zinc-sulfur nanocrystals has been proved by proton-induced X-ray multielement analyses (PIXE) and in vivo chelation with diethyldithiocarbamate (DEDTC). The aims of the present study were (a) to make the immersion-based capturing of zinc ions in zinc-sulfur nanocrystals work directly on sections and slices of fixed brain tissue, (b) to work out protocols that ensure zinc specificity and optimal quality of the staining, (c) to apply "immersion autometallography" (iZnS AMG ) to other tissues that contain zinc-enriched (ZEN) cells, and (d) to make the immersion approach work on unfixed fresh tissue.

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Distribution of bismuth in the brain after intraperitoneal dosing of bismuth subnitrate in mice: Implications for routes of entry of xenobiotic metals into the brain

Cited by 51 publications

References 49 publications

Microsurgical anatomy of the arterial basket of the conus medullaris

Microsurgical anatomy of the arterial basket of the conus medullaris

Interactions of Bismuth Complexes with Metallothionein(II)

Immersion Autometallography: Histochemical In Situ Capturing of Zinc Ions in Catalytic Zinc-Sulfur Nanocrystals

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