Dr. Meetha M. Medhora's laboratory is studying the effect of ionizing radiation on the vasculature of the lungs. We are also interested in the vaso-reactive and anti-apoptotic actions of EETs and 20-HETE (products of the essential fatty acid, arachidonic acid) on blood vessels.
Effects of ionizing radiation on the vasculature of the lungs
As part of the MCW Center for Countermeasures Against Radiation, we are identifying agents to mitigate radiological injury to the lungs. Using a rat model we have observed a single non-lethal dose of 10-15 Gy to the thorax to result in vascular injury after 6-8 weeks. Specifically in collaboration with the laboratory of Dr. Robert Molthen, an engineer at the Zablocki VA Medical Center, we measured a reduction in density, reactivity, distensibility and endothelial function accompanied by an increase in resistance, in the pulmonary vasculature. All the injuries except for vascular distensibility recover by one year. Currently we are testing a number of pharmaceutical reagents in an effort to identify mitigators and treatment for the radiation pneumonitis we observe.
Vasoreactive and antiapoptotic actions of EETs and 20-HETE (products of the essential fatty acid, arachidonic acid)
The endogenous fatty acids EETs and 20-HETE have potent vasoreactive and other properties. In collaboration with the laboratory of Dr. Elizabeth Jacobs we have demonstrated that EETs protect pulmonary arteries ex vivo using vessels from three species, human, mouse and rat. 20-HETE also protects rat pulmonary and cerebral arteries from hypoxia and reoxygenation injury ex vivo. We are currently studying the intracellular mechanisms for protection by these fatty acids.