NEUS-609 - Historical perspectives in cellular neuroscience

Deiters

Name: ____

Contribution: dissected individual neuron

Significance: revealed neurons are complex, process-bearing cells. Highlight structure of nervous tissue.

Franz Nissl

Name: ____

Contribution: invented the Nissl dye which stains Nissl bodies in the ER aka stains cell bodies of nerve cells

Significance: helped other scientist determine structure of nervous tissues

Camillo Golgi

Name: ____

Contribution: accidentally discovered black reaction of chrome-silver dye outlining entirety of a few nerves cells. Author of reticular theory

Significance: led to more discoveries about the structure of nervous tissue by him and other scientists

insight on how nerve cells are organized

Santiago Ramon y Cajal

Name: ____

Contribution: used the Golgi silver stain to map out different types of nerve cells and neurons as well as the whole retinal circuitry. Author of the neuron doctrine.

Significance: determined how nerve cells are actually organized, how they are connected based on their structure.

Luigi Galvani

Name: ____

Contribution: Created concept of “animal electricity” based on frog leg muscles stimulation

Significance: insight in basis of neurons’ electrical properties

Hodgkin and Huxley

Name: ____

Contribution: giant squid axon experiments determining polarized membranes as well as the change in polarization/charges as action potential signal.

Significance: determined the basis/reasons for the electrical properties of neurons

Loewi and Dale

Name: ____

Contribution: vagus nerve action on heart in solution in diff chambers experiment led to discovery of chemical neurotransmitter acetylcholine.

Significance: partially elucidated how neurons communicate with each other

Charles Sherrington

Name: ____

Contribution: determined that there were gaps between neurons based on reflexes circuits that were too fast to only be continuous nerve fibers.

Significance: determined structure behind neuron communication

Knoll and Ruska

Name: ____

Contribution: invented the electron microscope in Germany in 1930s

Significance: Applied to biological tissues in the 1950s

George Palade

Name: ____

Contribution: description of cellular organelles using electron microscopy

Significance: confirmed Sherrington concept of synapse

reticular theory

all neurons are continuous. They have continuous cytoplasmic flow with each other.

neuron doctrine

neurons are discrete, structurally and functionally independent cells. Correct theory.

advantages of Golgi staining method

• labels cell in their entirety

• high contrast, cells appear black against pale background

• stains <5% of total cells, leading to clear view of individual cell structure

disadvantages

• unpredictable results, label only a few cells at random (aka sampling problem)

• poor reproducibility, limited quantification of results

• time consuming (2-4 weeks)

• stains <5% of total cells which may lead to you missing something