sodium-dodecyl-sulfate and Hyperglycemia

Insulin-like growth factor-I (IGF-I) is implicated in the development, survival and maintenance of function of sympathetic and sensory neurons. These neurons are affected at an early stage during the course of diabetes. Reverse transcriptase polymerase chain reaction (RT-PCR) based assay revealed that rat superior cervical ganglia (SCG) express mRNA transcripts for IGF-I and its receptor. Moreover, specific membrane protein binding sites for IGF-I within the SCG have also been demonstrated using competition-inhibition and affinity cross-linking techniques. An induction of diabetes with streptozotocin (STZ, 55 mg/kg, i.v.) produced a marked decrease in the SCG levels of mRNA transcripts for IGF-I and its receptor. Concentrations of circulating IGF-I and its receptor protein within the SCG were also reduced in this disease state. Insulin treatment partially prevented diabetes-related alterations in circulating IGF-I and the SCG-IGF-I system. Overall, the data described in this study may be of value in understanding the pathogenetic mechanism(s) responsible for the development of diabetic sympathetic neuropathy.

Topics: Animals; Binding, Competitive; Diabetes Mellitus, Experimental; Electrophoresis, Polyacrylamide Gel; Female; Gene Expression Regulation; Hyperglycemia; Hypoglycemic Agents; Insulin; Insulin-Like Growth Factor I; Iodine Radioisotopes; Membrane Proteins; Polymerase Chain Reaction; Protein Binding; Rats; Rats, Sprague-Dawley; Receptor, IGF Type 1; RNA; RNA, Messenger; Sodium Dodecyl Sulfate; Superior Cervical Ganglion

Severe hyperglycemia can result in falsely high results for mean cell (erythrocyte) volume (MCV), which will also cause false results for erythrocyte indices calculated on the basis of MCV. Falsely high MCV results were obtained with the Technicon H1 and H2 analyzers and (to a lesser extent) with the Coulter T660. The H analyzers were more susceptible to this interference than was the Coulter T660. This difference in sensitivity of MCV to hyperglycemia can be explained by the use of sodium dodecyl sulfate in the Technicon erythrocyte diluent and by differences in incubation times. In severe hyperglycemia, results for MCV, mean cell hemoglobin concentration, and hematocrit obtained from electronic cell counters, especially Technicon H systems, are unreliable.

Topics: Artifacts; Detergents; Erythrocyte Indices; Fixatives; Glutaral; Hematologic Tests; Humans; Hyperglycemia; Predictive Value of Tests; Reference Values; Sodium Dodecyl Sulfate