Abstract
In order to elucidate the changes of cyclic nucleotides in renal failure, the concentrations of adenosine 3′, 5′-monophosphate (cAMP) and guanosine 3′, 5′-monophosphate (cGMP) in plasma and urine were determined by competitive protein binding assay and radioimmunoassay method respectively in patients with chronic renal failure (CRF) and in experimental animals with acute renal failure (ARF) induced by uranyl acetate injection.
The relationship between these cyclic nucleotides levels and peptide hormones (glucagon and parathyroid hormone : PTH) was also investigated.
The results obtained were as follows :
1. In CRF patients, plasma cAMP and cGMP levels were higher than those in normal subjects.
2. In CRF patients, the urinary excretion and renal clearance of cyclic nucleotides were decreased.
3. In dialyzed patients, plasma glucagon level was significantly increased, compared with that in normal subjects.
4. Plasma cAMP level was also significantly correlated with plasma levels of glucagon. On the contrary, the correlation with plasma PTH levels was not observed.
5. Plasma cGMP level was significantly correlated with mean blood pressure in dialyzed patients.
The experimental results on ARF rabbits showed the same tendency in the plama concentrations, renal clearances of cyclic nucleotides and plasma glucagon levels. Plasma levels of cAMP showed significant correlation with its glucagon levels. In the analysis of tissue concentration of cyclic nucleotides, significant decrease of cAMP in the renal cortex and increase of cGMP in the liver were noted.
It is concluded that the impairment of renal function and alteration of plasma peptide hormones appear to have influences on the elevated plasma levels of cyclic nucleotides in renal failure.
