A new discovery by researchers at the University of Georgia may help explain one aspect of the tangled problem. Using small pieces of left-over saphenous vein tissue from heart bypass surgeries, they compared the veins of white men and women and discovered a startling difference between them. They demonstrated for the first time dramatic differences in the density of receptors for a powerful and naturally occurring blood-borne substance called endothelin-1. And it's more bad news for white males.
"We won't entirely know the relevance of this study until we do the same experiments with arterial tissue, but it's an important first step," said Dr.Adviye Ergul of the University of Georgia's department of biochemistry and molecular biology. Collaborating with Ergul on the research were Dr. David Puett of the same department and Dr. Randall Tackett of the University of Georgia College of Pharmacy.
Results of the study were published this week in the May issue of the Journal of Pharmacology and Experimental Therapeutics.
Endothelin-1 (ET-1) is produced by cells that line the blood vessels and is a potent vasoconstrictor -- that is, a compound which causes vessels to contract. Ergul and Puett showed in 1996 that hypertensive blacks have four times as much endothelin-1 in their blood streams as hypertensive whites, and that hypertensive blacks have eight times more circulating ET-1 than blacks with normal blood pressure. The current study is the first to examine gender differences in ET-1.