Looking at neurons from all sides

A new technique that marries a fast-moving laser beam with a special microscope that look at tissues in different optical planes will enable scientists to get a three-dimensional view of neurons or nerve cells as they interact, said Baylor College of Medicine scientists in a report that appears today in the journal Nature Neuroscience.

“Most microscopes can only study cell function in two dimensions,” said Dr. Gaddum Duemani Reddy, an M.D./Ph.D. student at BCM at Houston and Rice University and also first author of the study. “To look at different planes, you have move your preparation (of cells) or the objective lens. That takes time, and we are looking at processes that happen in milliseconds.”

To solve that problem, he said, they developed a “trick” to quickly move a laser beam in three dimensions and then adapted that laser beam to the multi-photon microscope they were using. That allowed them to “see” the neuron’s function in three dimensions, giving them a much better view of its activity.

A multiphoton microscope looks much like a conventional, upright microscope but it has an adaption that allows it to look at tissues in sections. A conventional multiphoton microscope does that very slowly, he said.

“With ours, you can do it very quickly. We are starting to see how a single neuron behaves in our laboratory,” he said. The next step, he said, will be to use to it to look a clusters or colonies of neurons. This will enable them to actually see the neuronal interactions.

“At present, the technology is applied in my lab to study information processing of single neurons in brain slice preparations by 3D multi-site optical recording,” said Dr. Peter Saggau, professor of neuroscience at BCM and the paper’s senior author.

He is collaborating with two other labs on using the technology in other ways. In one, he said, researchers plan to use the technology to monitor nerve activity in the brains of lab animals in order study how populations of neurons communicate during visual stimulation. Another study attempts to use the technology to monitor stimulation of the acoustic nerve optically. Those scientists hope to reinstate hearing in lab animals whose inner ear receptors do not work.

Source: Baylor College of Medicine

Related stories:

FSU researchers make observing cell functions easier
Now that the genome (DNA) of humans and many other organisms have been sequenced, biologists are turning their attention to discovering how the many thousands of structural and control genes -- the “worker bees” of living cells that can turn genes on and off -- function.
Researchers Observe Hydrogen-Bond Exchange
Hydrogen bonds are quite small, on the level of a few angstroms. They can also be passed between two different molecules very quickly, at speeds of tens of times per second. But in spite of these properties, researchers have recently observed hydrogen-bond exchange taking place in real-time.
Iron 'snow' helps maintain Mercury's magnetic field, scientists say
New scientific evidence suggests that deep inside the planet Mercury, iron “snow” forms and falls toward the center of the planet, much like snowflakes form in Earth’s atmosphere and fall to the ground.
Unraveling the Genomic Code for Development
Scientists at the California Institute of Technology have produced the first complete description of the complex network of genes that create a particular type of cell in an organism.
Atomic force microscopy reveals liquids adjust viscosity when confined, shaken
Getting ketchup out of the bottle isn’t always easy. However, shaking the bottle before trying to pour allows the thick, gooey ketchup to flow more freely because it becomes more fluid when agitated. The opposite is not typically true – a liquid such as water does not become a gel when shaken.
Nanobacteria – Are They Alive?
Tiny particles called nanobacteria have intrigued researchers in many ways since their discovery 20 years ago, but perhaps the most controversial question they pose is whether or not they are alive.
Laser dissection of depression
Chinese investigators from Hefei and Dutch researchers in Amsterdam have collaborated using for the first time a combination of new elegant methodology in Depression research. They used postmortem human brain tissue that was donated to the Netherlands Brain Bank for research purposes and investigated a region in the basal part of the brain, the hypothalamus, that is known to be of crucial importance for the development of symptoms of depression.
Nanoparticles Provide Detailed View Inside Living Animals
Using nanoparticles designed specifically to produce a bright Raman spectroscopic signal, a team of investigators at the Center for Cancer Nanotechnology Excellence Focused on Therapy Response (Stanford CCNE) has shown that it can produce whole-body images in small animals that can reveal the location of tumors and track how these nanoparticles traffic through the body.

News discussion:

Medicine & Health news