+ Site Statistics
+ Resolve Accession
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
EurekaMag PDF Full Text Supply ServicePDF Full Text Supply Service
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
Submit PDF Full TextSubmit PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn
Follow on LinkedInFollow on Tumblr

+ Translate

The presynaptic grid a new approach

, : The presynaptic grid a new approach. Brain Research 184(1): 23-40

A new EM facility is described which enables systematic visualization of E-PTA[ethanolic phosphotungstic acid]-stained presynaptic grids in full en face position. This EM-facility is used to analyze the size and the number of dense projections of synaptic grids in different brain areas of the rabbit. The view that dense projections form an intrinsic part of all central synapses and are organized in a hexagonal or triangular pattern is supported. The observation of annulate and horseshoe-shaped synaptic grids agrees with previous observations on synaptic connections with subsynaptic plate perforations. A non-normal frequency distribution of dense projections per synaptic grid with distinct peaks is suggestive of the existence of distinct size classes of synaptic contacts. Analyses of the frequency distribution of dense projections in different areas and at different levels below the pial surface in adult animals point to a specificity of the distinct size classes related to the afferent origin or the target cell on which they are projecting. Investigation or grid size and number of dense projections during a period of rapid synaptogenesis reveals that newly formed synapses also have a specific size. The complementarity of dense projections and vesicle attachment sites implicit in the model of Akert et al (1972) was used to calculate the number of vesicle attachment sites per sq. .mu.m because of the density of projections per grid. The agreement between these values and those of Akert and Peper (1975), based on the analyses of vesicle attachment sites in freeze-etch specimen, is striking. The possible implications of these observations in relation to synaptic efficacy and neuronal microcircuitry are discussed.

Order PDF Full Text


Click here to order any other PDF Full Text

Accession: 006740097

PMID: 7357422

DOI: 10.1016/0006-8993(80)90585-5

PDF Full Text: The presynaptic grid a new approach

Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:

Other references

Balodis, I.M.; Wynne-Edwards, K.E.; Olmstead, M.C., 2011: The stress-response-dampening effects of placebo. This experiment used both biological and self-report measures to examine how alcohol modifies stress responses, and to test whether the interaction between these two factors alters risk-taking in healthy young adults. Participants were divided int...

Takatsu, T.; Tsutsumi, J., 1965: Selection and combination of diuretics. Nihon Rinsho. Japanese Journal of Clinical Medicine 23(11): 2149-2168

Hellgren, J.; Wadden, T.; Lansner, A.; Grillner, S., 1994: A continuous network model of the lamprey swimming rhythm generator-intersegmental coordination. Society for Neuroscience Abstracts 20(1-2): 1592

Duck, B.J.; Woolias, M., 1985: Reversed-phase high performance liquid chromatographic determination of carbaryl in postmortem specimens. A reversed-phase high performance liquid chromatographic (HPLC) method has been developed for the analysis of carbaryl in postmortem samples. It involves the use of an aqueous acetonitrile mobile phase to give rapid, reproducible analyses and an e...

Bellows, A. C., 1999: Urban food, health, and the environment: the case of Upper Silesia, Poland. In 1997, Poland celebrated 100 years of urban allotment agriculture. Typically conducted by women, retirees, and other reserve labour, this local food production has provided a measure of autonomy from the vagaries of inefficient production and fo...

Huda-Faujan, N.; Abdulamir, A.S.; Fatimah, A.B.; Anas, O.Muhammad.; Shuhaimi, M.; Yazid, A.M.; Loong, Y.Y., 2010: The impact of the level of the intestinal short chain Fatty acids in inflammatory bowel disease patients versus healthy subjects. The aim of this study was to determine the changes of short chain fatty acids (SCFAs) in faeces of inflammatory bowel disease (IBD) patients compared to healthy subjects. SCFAs such as pyruvic, lactic, formic, acetic, propionic, isobutyric and but...

Shepeleva L.F., 1986: Effect of spring flood on the productivity of floodplain meadows. Patterns of the dynamics of the aboveground phytomass of meadow communities of the Ob River[Russian SFSR, USSR] were studied over many years. A dispersion analysis was used to establish the fact that meadow productivity varied as a function of the...

Seret, B., 1990: Aulohalaelurus kanakorum n sp, a new species of catshark Carcharhiniformes, Scyliorhinidae, Atelomycterinae from New Caledonia. A new catshark, Aulohahaelurus kanakorum n. sp., is described from an adult male collected from off south-western New Caledonia. It is the second species in the genus Aulohalaelurus, previously restricted to western Australia. The new species is d...

Radojćić, M., 1971: Use of existing spirographic norms in Yugoslavia. Plucne Bolesti i Tuberkuloza 23(1): 40-42

Delmas, C.; Poussou, C., 1984: A new milking installation for small flocks of ewes. The installation and milking routine (for flocks of <150) make use of the information gained in a previous study that milk release in ewes is usually complete within 90 s of putting on teatcups and that most of the residual milk can be removed...