Original Serum Ribonuclease Activities and

The levels of serum ribonucleases (RNase) were determined in a control group of healthy adults and in groups of patients suffering from body weight loss secondary to Insulin Dependent Diabetes Mellitus, hyperthyroidism and hypothyroidism. The study also included a group of premature infants with body weight much less than normal. The results obtained support the correlation between the rise of serum ribonuclease levels and the extent of weight loss. These results also emphasise the importance of measuring the specific activities of both the alkaline and the acidic RNases and calculating the ratio of these activities for the correct assessment of the extent of weight loss in a certain pathological condition. Bahrain Med Bull 1995;17: Ribonucleases have been detected, identified and characterised in several organs and animal body fluids1-15. The ribonuclease (RNase) activity of the three human body fluids; serum, CSF and urine, is chromatographically heterogenous16. However, the extent and physical bases of this heterogeneity are unknown. Serum, for instance, contains at least six species of RNase activities separable by phosphocellulose column chromatography1,2,17,18. These six species of serum RNase activities have been categorized in two major classes distinguished by their pH optima for depolymerisation of RNA; acidic (pH 6.5) and alkaline (p