Episode 24: Pregnancy and Exercise

When a pregnant woman exercises, is it good for her fetus? That is the question that researchers Linda May of the Kansas City University of Medicine and Biosciences and Kathleen Gustafson of the University of Kansas Medical Center are trying to answer. Their work is ongoing, but it is good news, so far, for pregnant women who like to exercise. (Begins at 01:59)

Buzz in Physiology (Begins at 00:47)

Estrogen can halt the damage caused by a stroke by inactivating the protein, p53.

Researchers have found a way to diagnose overtraining syndrome in horses by measuring the secretion of nocturnal growth hormone.


Episode 23: Cool Water

Three physiologists tell us why the prescription “drink when you are thirsty” is usually the best guideline for deciding when and how much to drink. We will talk to Heinz Valtin of Dartmouth Medical School (retired); Mark Knepper, the chief of the Laboratory of Kidney & Electrolyte Metabolism of the National Heart Lung and Blood Institute; and Samuel Cheuvront, of the Thermal and Mountain Medicine Division of the U.S. Army Research Institute of Environmental Medicine about water consumption. They will answer the question: “Must I drink 64 ounces of water each day?” (Begins at 3:47)

To read the review of the eight-by-eight rule by Heinz Valtin, click here:

In the Buzz in Physiology, we look at studies involving a prosthetic device known as the Cheetah Flex Foot and whether it gives a runner who is a bilateral amputee an unfair advantage over limb-intact runners. We also summarize a study in mice in which adult bone marrow stem cells were used as a non-invasive therapy to repair cardiac tissue. And finally, we’ll look at a study that finds that electro-acupuncture successfully reduced sympathetic nerve activity, normalized menstrual cycles and reduced testosterone in women with polycystic ovarian syndrome. (Begins at 1:05)


Episode 22: Laughter: Good Medicine?

There is nothing like a good laugh, is there? It not only feels great to laugh, it can feel great to hear other people laugh. Beyond brightening the mood, can laughter provide tangible health benefits?

Lee Berk of Loma Linda University in California has done a series of studies on laughter and its possible physiological effects. We will talk to him about his latest study, done over the course of a year with diabetic patients. (Begins at 3:50)

In this month’s Buzz in Physiology (begins at 0:51), we look at studies that provide possible explanations for:

  1. Why pregnant Andean give birth to larger babies at high altitude, compared to European women
  2. How certain side effects in some medical procedures may trace back to a solvent found in plastic tubing

Total Time: 9:47


Episode 21: Blood Pressure and the Brain

Did you know that there is a sensor in the nerve endings in the carotid artery that rapidly lowers blood pressure when stimulated? This discovery may one day allow people who are hypertensive to lower their blood pressure by using a pacemaker-like device that stimulates the nerve endings in the blood vessels.

In this edition of Life Lines, we talk to Francois Abboud, of the Carver College of Medicine at the University of Iowa whose research identified this sensor. We’ll also talk to him about his recent research looking at the genes that regulate ion channels, microscopic gates that move chemicals in and out of cells, and that play a role in the signaling between the brain and the blood vessels. In experiments with animals, Dr. Abboud and his colleagues deleted one specific ion channel and found that the animals developed high blood pressure. (Begins at 03:51)

We’ll also talk to Ann M. Schreihofer, of the Medical College of Georgia, who focuses on the role the brain plays in increasing sympathetic nervous activity, which contributes to many forms of hypertension (high blood pressure). Among the questions her research seeks to answer is why people who are obese become hypertensive.

The Schreihofer laboratory has also been looking at sleep apnea and whether it is possible to improve respiratory function as a way to reduce the sympathetic activity that leads to obesity and hypertension. (Begins at 09:43)

In the Buzz in Physiology (begins at 1:24), we have studies on:

  1. resistance training and octogenarians
  2. muscle atrophy during lengthy space missions
  3. belly fat, inflammation and exercise

The photo in our logo is a neuron from the rostral ventral lateral medulla of the brain stem and was provided by Dr. Schreihofer.

Total running time: 16:45.