원저 : 연속적 한외여과와 혈액투석중 혈장 ANP 의 변화

Plasma atrial natriuretic peptide (ANP) has been known to be a kind of peptide hormone and to have actions of natriuresis, diuresis and vasodilatation. It has been suggested that plasma ANP may be secreted from the cardiac atrium in response to extracellular fluid volume expansion to maintain blood volume homeostasis, and its level may be raised in volume overloaded conditions, such as congestive heart failure, chronic renal failure and the syndrome of inappropriate antidiuretic hormone secretion. We investigated the effect of fluid removal by sequential ultrafiltration and hemodialysis on circulating plasma ANP in 14 volume overloaded patients with chronic renal failure. The results were as follows: 1) The mean dry weight of patients was 58.3±0.4 kg and the predialytic weight gain was 3.4±0.9 kg. The amount of fluid removal by sequential ultrafilt-ration was 1176±31.7 ml (about 2% of predialytic body weight) and postdialytic weight loss was 3.1±0.3 kg. Systolic and diastolic blood pressures were not significantly changed during sequential ultrafiltration and hemodialysis, Plasma osmolality, BUN and K+ levels were not significantly changed after ultrafiltration but were significantly decreased after hemodialysis. 2) Plasma ANP levels were raised in all patients (mean±SE 205.3±30.7pg/ml, n=l4) compared with healthy contro1s (40.9±4.4 pg/ml, n=16), but showed considerable interpatient variability. 3) Plasma ANP levels fell with fluid removal during ultrafiltration (123.4±4.2 pg/ml, p<0.025) and again as fluid was removed during hemodialysis (88.7±3.1 pg/ml, p<0.05). 4) There was no significant correlation between predialytic weight gain and plasma ANP levels, and between postdialytic weight loss and plasma ANP levels. In conclusion, this study showed that the plasma ANP level was raised as body fluid volume increased in patients with chronic renal failure and fell with fluid removal after dialysis. These findings suggest that changes in body fluid volume play an important role in the regulation of ANP secretion.