The effects of genetic factors on selected indicators of the activity of the sympathoadrenal system and the renin-angiotensin-aldosterone system in twins.
BACKGROUND
There are numerous data indicating a significant role of the sympathoadrenal system and the reninangiotensin- aldosterone system in the regulation of blood pressure and the pathogenesis of essential hypertension. However, the genetic background of essential hypertension remains unclear.


OBJECTIVE
To determine the effects of genetic factors on selected indicators of the activity of the sympathoadrenal system and the renin-angiotensin-aldosterone system in twins.


METHODS
We studied 39 monozygotic twin pairs (age 33+/-7 years) and 37 same-gender dizygotic twin pairs (age 36+/-7 years). We measured blood and urine adrenaline (A), noradrenaline (NA), dopamine (DA) and aldosterone (ALD) levels, as well as plasma renin activity (PRA) and serum angiotensin-converting enzyme (ACE) activity. Parameters of the genetic models for age- and gender-adjusted data were estimated by model fitting and path analysis technique using LISREL 8.


RESULTS
The effects of genetic factors on the variability of blood and urine catecholamine levels were 69% and 65% for A, 42% and 76% for NA, and 58% and 40% for DA, respectively. We also found shared environmental components for blood NA (28%) and urine DA (17%). Genetic factors accounted for 36% of the variability of PRA and 80% of the variability of ACE. ALD levels were related only to environmental factors (including a shared environmental component, estimated at 25%, for urine ALD).


CONCLUSIONS
We found significant effects of genetic factors on the activity of the sympathoadrenal system, as indicated by blood and urine catecholamine levels. We also found the effect of genetic factors on PRA and ACE, but not on aldosterone levels.
Jedrusik
Piotr
P
Department of Internal Medicine, Hypertension and Angiology, Warsaw Medical University, Warsaw, Poland.
Januszewicz
Andrzej
A
Busjahn
Andreas
A
Wocial
Bozenna
B
Ignatowska-Switalska
Hanna
H
Strelau
Jan
J
C Luft
Friedrich
F
Januszewicz
Włodzimierz
W
D000311:Adrenal Glands / Q000503:physiopathology*; D000328:Adult; D000450:Aldosterone / Q000097:blood / Q000652:urine; D001794:Blood Pressure / Q000235:genetics*; D004298:Dopamine / Q000097:blood / Q000652:urine; D004837:Epinephrine / Q000097:blood / Q000652:urine; D005260:Female; D006801:Humans; D006973:Hypertension / Q000235:genetics*; D008297:Male; D009638:Norepinephrine / Q000097:blood / Q000652:urine; D007703:Peptidyl-Dipeptidase A / Q000097:blood; D012083:Renin / Q000097:blood; D012084:Renin-Angiotensin System / Q000235:genetics*; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic
D000450:Aldosterone; D007703:Peptidyl-Dipeptidase A; D012083:Renin; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine