Francisco J Fuster

804-10-2676

BIOL-3095

RISE Program

Seminar Summary:

From the Gut to Graduate School: An Interesting Journey

In this seminar Ms. Eileen Rodriguez presents her choice between following a career in medicine

or one in research. After conducting research she noticed that her true liking is in investigation.

She now studies in Michigan State University and she presented her investigation in

gastrointestinal motility.

Forty-one (41%) of gastrointestinal (GI) problems have to do with motility. Problems in motility

have to do with relaxation or contraction of the smooth muscle in the GI tract, producing

anomalies like indigestion, constipation, or diarrhea. These problems reduce the quality of life in

the people who suffer from this ailment. She learned, as she conducted her research that

contractions occur with the excitation of the smooth muscle in the GI tract when the myenteric

plexus (a group of nerve cells) is stimulated with electrical charges. She then observed as the

smooth muscle slowly relaxed and returned to its normal state.

Certain compounds can hyperpolarize by changing their concentrations in the nerve terminals of

the cells and vice versa, to relax the smooth muscle. Nitric oxide (NO) is the compound that was

mainly observed in this research. She experimented by blocking the calcium ions’ path to the

nitric oxide synthase (nNOS). The compound used to specifically block the R-type channels of

calcium to the nNOS was NiCl2. Another compound used was NLA which inhibited the nNOS

which assuring that no NO was being produced. Without the concentration of calcium, the

production of NO was stopped and the smooth muscle failed to relax.

She plans to use other drugs to block other passages that regulate contraction and relaxation to

later develop a drug that can alleviate the symptoms of GI tract motility.

Questions for Eileen:

Does NANC react to high concentrations of NO as a reflex?

Does the myenteric plexus regulate NO levels, or its production?

What finally convinced you to follow a career in investigation?