The study confirmed previous findings that tobacco smoke could possibly harm cardiovascular function. In addition, it extended those findings by showing that:
- cardiovascular responses during brief exposures were similar to those found during longer or higher-level exposures
- the response occurs with different types of smoke (tobacco, cooking oil and wood smoke)
- men respond to environmental tobacco smoke with a greater increase in indexes of sympathetic outflow to blood vessels than do women
The sympathetic nervous system produces the “fight or flight” response, which drives the heart and blood pressure and may cause damage if activated too long. Women respond with a greater parasympathetic response, dubbed “rest and digest,” which acts as a brake on the heart and blood pressure.
The study, Autonomic responses of men and women to particulate exposures, was conducted by Joyce McClendon Evans, Abhijit Patwardhan, Ashwin Jayanthi and Charles Knapp of the University of Kentucky; Roger Jenkins and Ralph Ilgner of the Oak Ridge National Laboratory; and Eric Hartman of CustomKYnetics, Inc. Ms. Evans will present the findings during the 122nd annual meeting of The American Physiological Society (www.the-aps.org/press), which is part of the Experimental Biology 2009 conference. The meeting will take place April 18-22 in New Orleans.
Controlled smoke exposures
Accumulating evidence indicates that an increase in air pollution is associated with an increase in heart attacks and deaths. These pollutants, including tobacco and cooking oil smoke, contain fine particles that evoke responses from heart and blood vessels indicating effects on their function.
This study briefly exposed people to low levels of common pollutants and measured their cardiovascular and cardiorespiratory responses. Forty healthy non-smokers (21 women, 19 men) whose average age was 35 participated in the experiment. The researchers exposed the participants to secondhand cigarette smoke, wood smoke or cooking oil smoke in separate trials as they sat in a 10-by-10-foot environmental chamber. The researchers cleared the air in the chamber after each trial.
They measured respiratory and cardiovascular function, including heart rate variability, breathing and blood pressure. These measures, in turn, gave researchers a picture of how the heart, circulatory and respiratory systems were reacting to the pollutants.
The study found that, particularly among men, exposure to smoke changed breathing patterns, raised blood pressure oscillations in peripheral arteries and shifted control of heart rate toward sympathetic domination. The sympathetic nervous system becomes active during times of stress, but can cause harm to the heart and blood vessels if activated too often or too long.
Women did not have a strong sympathetic response to the pollutants, a healthier response in the face of frequent exposure. That men would respond differently is not a surprise: women tend to have stronger parasympathetic responses, which are more protective of the cardiovascular system, Ms. Evans said.
These results confirm results from earlier studies, but with exposures that were at lower levels and for shorter lengths of time. The study also extended the findings in several ways, including finding that men and women respond differently.
“I was surprised we got statistically significant results with this low level of exposure,” Ms Evans said. “If we can detect these effects with smaller exposures, then the public health hazard from cigarettes and other particulate exposures may have been underestimated.”
The experimental protocols were reviewed and approved by the Institutional Review Boards that oversee human studies at both the University of Kentucky and Oak Ridge National Laboratory.
Physiology is the study of how molecules, cells, tissues and organs function to create health or disease. The American Physiological Society (APS) has been an integral part of this scientific discovery process since it was established in 1887.
Donna Krupa | EurekAlert!
Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT
Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine