Genetic and epidemiological studies on electrolyte transport systems in XXXX .

@entity1 @entity101 @entity1372 @entity412 @entity972 @entity1091
In recent years several different tests of cations in @entity1 cells have been studied to detect and to define possible roles in the development of essential @entity101 . The goal of this report is to summarize what has been learned in genetic and epidemiological studies of @entity1 populations. The seven tests reviewed in greatest detail include @entity1372 - @entity1091 countertransport, intraerythrocytic @entity1372 , @entity1372 (or @entity1091 )- @entity972 cotransport, @entity1091 leak, @entity1372 - @entity972 ATPase pump, @entity1372 pump sites (ouabain binding), and circulating @entity1372 pump inhibitor ('digoxin-like factor' in some studies). Countertransport, intraerythrocytic @entity1372 and cotransport consistently show different values in @entity101 compared to normotensives and even in normotensives with a positive family history of @entity101 when compared to controls without a positive family history. Thorough genetic studies have been carried out only for @entity1372 - @entity1091 countertransport and intraerythrocytic @entity1372 . Both of these tests are highly heritable with a combination of both polygenic and major gene effects. Cotransport, leak, and pump sites also seem to be quite significantly heritable whereas the ATPase pump activity and the circulating pump inhibitor seem to be largely determined by nongenetic factors. Some of the most dramatic changes in these tests have been observed during pregnancy. Significant increases are seen in countertransport, cotransport, ouabain binding sites, and digoxin-like factor. Oral contraceptives also seem to affect at least cotransport. Plasma @entity412 level and body weight are some of the strongest correlates of countertransport, cotransport, and @entity1091 leak. Cotransport increases with higher dietary @entity1372 intake and decreases with the use of the diuretic medication. In the current developmental stage these tests have several significant limitations. In most population studies there is a considerable overlap of test values between @entity1 with high and normal blood pressure. There are substantial variations in the methods used by different laboratories for the same tests. They are expensive, complex and usually must be done on fresh cells. There are conflicts between the results of several different reported studies that could be due to the way in which their subjects were selected, the effects of medications or other uncontrolled variables, or even due to the differences in laboratory methodologies.(ABSTRACT TRUNCATED AT 400 WORDS)
