Biomaterial Database

Two different types of lysis of chromaffin granules characterised by freeze-fracture electron microscopy and photon correlation spectroscopy. 1990

J Engel, and Y A Ermakov, and W Richter, and E Donath

Department of Biology, Humboldt University, Berlin, G.D.R.

When bovine chromaffin granules are incubated in hyperosmolar sucrose solutions and subsequently transferred back towards isoosmolarity they undergo lysis ('hyperosmotic relaxation lysis'). This type of lysis was compared with the common effect of hypotonic lysis by means of photon correlation spectroscopy (PCS) and freeze-fracture electron microscopy. Both methods revealed differences regarding mean sizes and size distributions of granules lysing under either hypotonic or hypertonic conditions. However, the results obtained by these two methods were not consistent. In the case of hypotonic lysis, a nonmonotonic behaviour of the mean diameter as a function of the sucrose concentration was observed by PCS, but not in the micrographs. From EM size determinations we obtained a decrease in the mean diameter and an increase of the width of the distribution due to the appearance of small (50-200 nm) vesicles. Probably these vesicles are intragranular vesicles released during lysis. The maximum in photon correlation spectroscopy (PCS) diameter being 140% of the isotonic diameter is shown to be caused by the changing size distribution and geometry of the lysing granules. In the case of hyperosmotic relaxation, micrographs revealed that originally shrunken, nonspherical granules regained their spherical shape and formed small (60 nm) vesicles upon lysis. In contrast, no difference was observed between the sizes of granules prior to and after hyperosmotic relaxation by means of PCS. The paper discusses the validity of intensity-weighted light scattering data of polydisperse particle suspensions with changing size distributions. The mechanism of hyperosmotic relaxation lysis is considered.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009997	Osmotic Pressure	The pressure required to prevent the passage of solvent through a semipermeable membrane that separates a pure solvent from a solution of the solvent and solute or that separates different concentrations of a solution. It is proportional to the osmolality of the solution.	Osmotic Shock,Hypertonic Shock,Hypertonic Stress,Hypotonic Shock,Hypotonic Stress,Osmotic Stress,Hypertonic Shocks,Hypertonic Stresses,Hypotonic Shocks,Hypotonic Stresses,Osmotic Pressures,Osmotic Shocks,Osmotic Stresses,Pressure, Osmotic,Pressures, Osmotic,Shock, Hypertonic,Shock, Hypotonic,Shock, Osmotic,Shocks, Hypertonic,Shocks, Hypotonic,Shocks, Osmotic,Stress, Hypertonic,Stress, Hypotonic,Stress, Osmotic,Stresses, Hypertonic,Stresses, Hypotonic,Stresses, Osmotic
D002395	Catecholamines	A general class of ortho-dihydroxyphenylalkylamines derived from TYROSINE.	Catecholamine,Sympathin,Sympathins
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D002837	Chromaffin Granules	Organelles in CHROMAFFIN CELLS located in the adrenal glands and various other organs. These granules are the site of the synthesis, storage, metabolism, and secretion of EPINEPHRINE and NOREPINEPHRINE.	Chromaffin Granule,Granule, Chromaffin
D005614	Freeze Fracturing	Preparation for electron microscopy of minute replicas of exposed surfaces of the cell which have been ruptured in the frozen state. The specimen is frozen, then cleaved under high vacuum at the same temperature. The exposed surface is shadowed with carbon and platinum and coated with carbon to obtain a carbon replica.	Fracturing, Freeze,Fracturings, Freeze,Freeze Fracturings
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013057	Spectrum Analysis	The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Spectroscopy,Analysis, Spectrum,Spectrometry