Life Lines - The Podcast of The American Physiological Society

Lucy Brown, a neuroscientist at the Albert Einstein School of Medicine, has studied romantic love using functional magnetic resonance imaging. Dr. Brown will talk about her studies on what happens in our brains at different stages of love: falling in love, being rejected by a lover, and longterm love. Obstructive sleep apnea is the most commonly diagnosed condition among sleep-related breathing disorders and can lead to debilitating and sometimes fatal consequences for the 18 million Americans who have been diagnosed with the disorder.

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)

In this episode, APS Executive Director Martin Frank talks with University of California physiologist John West about snorkeling elephants, galloping race horses and flying pigeons.

Marshall Montrose tells us why the stomach doesn't digest itself.

And finally, Greg Atkinson describes the benefits the afternoon nap may have for your heart. For the study abstract click here.

The intro and outro music for the Life Lines podcast is from Body Notes, composed by Hector Rasgado-Flores and performed by the San Diego Chamber Orchestra.

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.

The Buzz in Physiology: (Begins at 1:34) A quick look at studies from APS journals that have been in the news.Athletic Performance and Caffeine: (Begins at 3:05) Taking caffeine and carbohydrates together following exercise refuels the muscles more rapidly, according to a study from the Journal of Applied Physiology done by Australian researcher John Hawley of the Royal Melbourne Institute of Technology in Australia.Drinking It In: (Begins at 12:55) The discovery of how sugar is absorbed into the small intestine led to oral rehydration therapy and the development of rehydrating sports drinks such as Gatorade. A conversation with the man who made that discovery: Stanley Schultz of the University of Texas Medical School.You can read Dr. Schultz's historical perspectives paper "From a pump handle to oral rehydration therapy: a model of translational research" by clicking here. The music that you hear at the beginning and end of the program is Body Notes, composed by scientist-musician (and APS member) Hector Rasgado-Flores. The San Diego Chamber Orchestra performs. Running Time: 24:01Related Press Releases:Sweet tooth and GLUT2 GeneAging and Caloric RestrictionHigh-intensity Exercise