Effect of long-term low-dose aluminum-containing agents on hemoglobin synthesis in patients with chronic renal insufficiency.

To investigate the possible toxic effects of long-term low-dose exposure to A1-containing agents in 55 patients with chronic renal insufficiency (CRI), 37 patients received A1(OH)3 1 tablet 3 times per day (about 302 mg/day of elemental A1) for 3 months and another 18 were used as a control group. The hematological, iron status and A1 data were measured before and after the study. CRI patients who had ingested A1-containing agents for 3 months had significant decreases in hematological parameters and increases in serum A1 and daily urinary A1 excretion. Serum ferritin negatively correlated with serum A1 (r = -0.586, p < 0.0005), and hemoglobin (Hb) positively correlated with renal A1 clearance (r = 0.573, p < 0.0005) and logarithmic transformation of serum A1 (r = -0.437, p < 0.01) in these patients, despite no significant correlations between initially basal hematological and A1 parameters. But there were no significant differences between variables of A1 and hematological parameters before and after 3 months of follow-up in the control group. All factors correlating with Hb were measured with stepwise regression analysis; renal A1 clearance, creatinine clearance (Ccr) and serum iron were the most significant correlation factors with Hb. After Ccr and serum iron had been adjusted, Hb (b = 0.069 +/- 0.02; p < 0.05) still positively correlated with renal A1 clearance. Comparing patients who had reduced Hb (at least 0.5 g/dl) and those who did not, the response group had a lower basal (Ccr, a higher serum A1 and a lower renal A1 clearance after A1 loading for 3 months. In conclusion, A1 does play a role in the significant reduction of Hb and hematocrit in CRI patients after A1 loading for 3 months, and patients with a lower Ccr may easily develop A1-induced hematologically toxic effects. A1-containing agents should be used with care in long-term therapies of CRI patients.

The content and composition of immunoreactive somatostatin in monkey pancreas.

A highly sensitive and specific radioimmunoassay (RIA) was developed for analyzing somatostatin (SRIF-LI). The monkey pancreas was lyophilized and extracted with 2N acetic acid. The content and composition of immunoreactive somatostatin in monkey pancreas were then evaluated by chromatography process and RIA. The concentration of SRIF-LI in monkey pancreas was around 513.8 ng/g dry weight. At least 3 components of SRIF-LI were detected in pancreatic extracts. The major component of SRIF-LI (about 92%) was SS-14, and other two were SS-28 and a form bigger than SS-28.