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By Sherry F. Pruitt

An Arkansas State University professor has been involved with nicotine research on rats since last summer and has been awarded an additional grant to continue his research.

"Specifically, what we're looking at is the effects of nicotine on brain function," said Dr. Roger Buchanan, associate professor in the Department of Biological Sciences.

However, he is not investigating nicotine addiction or the cancer-causing agents in cigarettes, he said.

Research suggests that nicotine has some effects on the basic processes of the brain in unaddicted rats.

"We have found -- and I think this is the first time that this has been found -- that nicotine has some effects on some fundamental brain processes," he said.

Buchanan has been working with Dr. Edgar Garcia-Rill and Dr. Robert Skinner, both neuro-scientists in the Department of Anatomy at the University of Arkansas Medical Sciences.

The project was originally funded by the National Institutes of Health in Washington D.C. through the Arkansas Biomedical Research Infrastructure Network. Although ASU was involved, the lead institution was UAMS, Buchanan said. ASU's part of the $7 million to $8 million grant was about $20,000, he said.

Since then, ASU and UAMS have received additional funding from the Arkansas Biosciences Institute in the amount of $100,000.

Buchanan explained the process the researchers used to compile the data.

"For example, when you hear a loud noise, you jump. Technically, that's called a startle reflex. It's common in all animals," he said. "There, of course, is brain activity that produces that jump. In fact the jump is about the last thing that happens in terms of what the brain's doing."

When someone hears a loud, unexpected noise, the noise enters the ear and the ear sends a message to the brain, which tries to identify the noise received.

"Your brain identifies what it is and where it came from," he said.

Shortly thereafter, a second signal goes to the brain, which is an alert or an arousal signal.

"Arousal in this case refers to paying attention. And that is a signal that goes up to your brain and says, 'Hey, this was something that we didn't expect. It was a loud, sudden noise and you need to pay attention... In response to that you get the jump. The jump is really part of an attempt to get your muscles to stop what they are doing so if they need to respond to the noise, they can," Buchanan explained.

Nicotine affects that arousal signal or that attention signal, he stated.

"It lowers the strength of the signal and it slows it down; it takes it longer to get there -- a few milliseconds," he said.

The fact that schizophrenics smoke excessively has been known for some time, Buchanan noted, but researchers didn't know the reason.

"They don't just chain smoke. They smoke as often as they can possibly get a cigarette in their mouth," he said. "What they're probably doing is self-medicating. If they keep the nicotine levels in their bodies high, it helps alleviate their symptoms."

A normal person gets a strong signal when he hears a noise. If he hears another noise a second or so later, he gets almost no signal, Buchanan explained.

"Your brain has already paid attention. It doesn't matter," he said.

When a schizophrenic hears a noise, he gets a signal. When he hears another noise a half a second later, he gets another signal," he said. "It never goes away. We call that habituation... The signal never decreases."

However, if a schizophrenic smokes enough cigarettes and gets enough nicotine, it will decrease the size of that signal, which may help alleviate their symptoms, he added.

The phenomenon probably does not affect people who are addicted to nicotine, but it may have when they began smoking.

"People who are addicted -- their brain changes to compensate for it," he said.

The same signal is very small in autistic children, and it stays small, he said.

"We don't know for sure. Maybe the problem is that their brain doesn't know -- it isn't being told -- to pay attention to stuff," Buchanan stated.

Schizophrenics cannot tell what to pay attention to and what to ignore because they get the same signal every time.

"It seems possible that that is why they tend to hear voices and have delusions. You can imagine if your brain was always in that state. You couldn't pay attention to much of anything, and it would be easy to misinterpret what you did pay attention to," he explained.

Buchanan said the nicotine research on rats will continue with researchers looking at the offspring of addicted mother rats.

"There's some evidence in humans that children of mothers who smoke tend to have social problems as they get older -- in their teen years -- because they were exposed to nicotine while she was pregnant."

Buchanan said his research will be able to continue because of the ABI grant funding. Buchanan's research was one of several faculty research projects that was announced as the first group of proposals funded through the ABI.

His proposal was titled "Arousal and Sensory Gating: Effects of Acute and Chronic Exposures to Nicotine."

Total ABI funding for the projects amounts to about $1.8 million.

Faculty members, their departments and their successful proposals, released by university officials at the end of January, include:

• Drs. Kristin Biondolillo and Amy Pearce, Psychology and Counseling -- "Establishing the Stimulus Properties of Nicotine."

• Drs. Thomas Risch and Jerry Farris, Biological Sciences -- "Assessing the Benefits of Genetically Modified Crops: using small mammal models."

• Drs. James Bednarz, Jeannette Loutsch and Thomas Risch, Biological Sciences -- "Vector Ecology of West Nile Virus: an assessment of human risk in the Delta Region of Arkansas."

• Dr. Jeanette Loutsch, Biological Sciences -- "The effects of asthma therapy and second-hand smoke on the reactivation profile of herpes simplex type 1 in the mouse eye model."

• Drs. Robyn Hannigan and Jon Russ, Chemistry and Physics -- "Human Hair as a Biomarker for Exposure to Tobacco Smoke."

• Drs. William Burns and Scott Reeve, Chemistry and Physics -- "A Novel Application of Tunable Diode Laser Absorption Spectroscope: The Fast and Accurate Analysis of Gas Phase Constituents of Environmental Tobacco Smoke."

• Dr. Anne Grippo, Biological Sciences -- "Nicotine and Ephedrine Interactions: Effects on the Cardiovascular System."

Two proposals, "Social Assessment of Pharmaceuticals," from Dr. Andrew Knight, Sociology, and Dr. Patrick Stewart, Political Science, and "Biopharmaceuticals -- Assessment of Economic and Environmental Issues," from Drs. Gauri Guha, Sarath Nonis and Richard Segall, Economics and Decision Sciences, were so clearly related that Dr. Jan Duggar, dean of the College of Business, was asked to direct a focus area grant combining the two. The new focus area is "Social, Economic and Regulatory Studies."