ZIB

Treffer pro Seite

Treffer 1 - 2 | 2 Treffer

Sortierung

Digitale Medien

Heterogeneity of the calcium-induced permeability transition in isolated non-synaptic brain mitochondria (2002)

Kristián, Tibor ; Weatherby, Tina M. ; Bates, Timothy E. ; [weitere]

Oxford, UK : Blackwell Science Ltd

Journal of neurochemistry 83 (2002), S. 0

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1471-4159

Quelle: Blackwell Publishing Journal Backfiles 1879-2005

Thema: Medizin

Notizen: Calcium overload of neural cell mitochondria plays a key role in excitotoxic and ischemic brain injury. This study tested the hypothesis that brain mitochondria consist of subpopulations with differential sensitivity to calcium-induced inner membrane permeability transition, and that this sensitivity is greatly reduced by physiological levels of adenine nucleotides. Isolated non-synaptosomal rat brain mitochondria were incubated in a potassium-based medium in the absence or presence of ATP or ADP. Measurements were made of medium and intramitochondrial free calcium, light scattering, mitochondrial ultrastructure, and the elemental composition of electron-opaque deposits within mitochondria treated with calcium. In the absence of adenine nucleotides, calcium induced a partial decrease in light scattering, accompanied by three distinct ultrastructural morphologies, including large-amplitude swelling, matrix vacuolization and a normal appearance. In the presence of ATP or ADP the mitochondrial calcium uptake capacity was greatly enhanced and calcium induced an increase rather than a decrease in mitochondrial light scattering. Approximately 10% of the mitochondria appeared damaged and the rest contained electron-dense precipitates that contained calcium, as determined by electron-energy loss spectroscopy. These results indicate that brain mitochondria are heterogeneous in their response to calcium. In the absence of adenine nucleotides, approximately 20% of the mitochondrial population exhibit morphological alterations consistent with activation of the permeability transition, but less than 10% exhibit evidence of osmotic swelling and membrane disruption in the presence of ATP or ADP.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1046/j.1471-4159.2002.01238.x

Permalink

Bibliothek	Standort	Signatur	Band/Heft/Jahr	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

Digitale Medien

Developmental changes in structure and polypeptide profile of the androgenic gland of the freshwater prawn Macrobrachium rosenbergii (2000)

Sun, Piera S. ; Weatherby, Tina M. ; Dunlap, Marilyn F. ; [weitere]

Springer

Aquaculture international 8 (2000), S. 327-334

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1573-143X

Schlagwort(e): androgenic gland ; androgenic hormone ; freshwater prawn ; light and transmission electron microscopy ; (Macrobrachium rosenbergii) ; male morphotypes ; sex-differentiation sodium dodecyl sulfate polyacrylamide gel electrophoresis

Quelle: Springer Online Journal Archives 1860-2000

Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft

Notizen: Abstract Although the mechanism of sex-differentiation in crustaceans has yet to be defined, the androgenic gland (AG) is thought to be the exclusive organ that produces the androgenic hormone (AH) which induces male sexual development. This paper presents results of light and transmission electron microscopy and total protein analysis of androgenic glands from three male morphotypes (orange-claw, orange-blue-claw and blue-claw) of the freshwater prawn, Macrobrachium rosenbergii. Highest protein content (76 µg//AG) was found in the blue-claw morphotype as compared to the orange-blue-claw (45 µg/AG) and the orange-claw morphotype (19 µg/AG). Sodiumdodecyl sulfate polyacrylamide gel electrophoresis (SDS-page) analysis of the cell free extract of the AG from the three morphotypes revealed four polypeptides (∼16, ∼18, ∼23 and ∼26 Kd) which quantitatively increase from the sexually immature orange-claw to the sexually mature blue-claw morphotype. The 16 and 18 Kd polypeptides could be the AHs.