ABSTRACT
Growth hormone (GH) levels were measured in 12 patients with myotonic dystrophy (MD; 7 men and 5 women, aged 21-49 years) and 14 volunteers after administration of 100 micrograms GH-releasing hormone (GHRH; 1-29). A 75-g oral glucose tolerance test was carried out to determine glucose, insulin, plasma C-peptide, and urinary C-peptide. The GH level in six MD patients responded normally to GHRH (group I), with a peak of 17.1 +/- 1.46 micrograms/l, compared with controls (27.8 +/- 19.6 micrograms/l, NS), and that in the other six patients responded subnormally, with a peak of 3.15 +/- 1.46 micrograms/l, lower than in controls and in group I patients (P < 0.001). In group I the insulin response to the glucose tolerance test showed hyperinsulinism and was lower than that in group II patients; stimulated C-peptide was also higher in group II than in group I and in controls; urinary C-peptide levels were parallel to those in previous data. In all MD patients there were a negative correlation between absolute values of GH response to GHRH and insulin response to glucose tolerance test (r = -0.79, P < 0.001). Our data suggest that the failure in GH release and peripheral insulin action is due to a generalized defect in cellular membrane function in MD patients.
Subject(s)
Growth Hormone/metabolism , Insulin/metabolism , Myotonic Dystrophy/physiopathology , Adult , C-Peptide/metabolism , Evaluation Studies as Topic , Female , Glucose Tolerance Test , Humans , Insulin Secretion , Male , Middle AgedABSTRACT
The Enzymun-Test System ES-600 is a fully automated analyser for the Clinical Chemistry hormone laboratory. The Enzymun-Test prolactin, an enzyme immunoassay, is based on a sandwich technique using two monoclonal antibodies, one coated onto tubes and the other labelled with peroxidase. We have studied the measurement of prolactin concentration in serum and compared the results obtained with both this system and with the manual IRMA used in our laboratory. The within-day imprecision gave the following CV (n = 20): 6% at 64 mU/l, 1% at 379 mU/l and 2% at 1232.1 mU/l. The CV for between-day imprecision (n = 20) was 10%, 8% and 6%, respectively. The detection limit was 4 mU/l and linearity was demonstrated with geometric dilutions of a highly concentrated serum. We observed an average recovery of 104%, ranging 95.6%-110%. The calculated carryover was of 0.05%, and there was no trend in the measurements to indicate the occurrence of long series drift. In the study of interchangeability (Passing-Bablok regression test) we obtained a linear equation: y (ES-600) = 3.16 mU/l + 0.82 x (IRMA), with the confidence intervals (95%) a(-30.69, 21.53); b(0.73, 0.99); and a correlation coefficient of r = 0.98.
Subject(s)
Immunoenzyme Techniques/instrumentation , Prolactin/blood , Blood Chemical Analysis/instrumentation , Blood Chemical Analysis/statistics & numerical data , Evaluation Studies as Topic , Humans , Immunoenzyme Techniques/statistics & numerical data , Immunoradiometric Assay , Sensitivity and SpecificityABSTRACT
The basic aspects of steroid hormones transport, their tissular release and the interpretation of salivary testosterone values as a reflect of the free hormone in serum are reviewed in this article, as well as the salivary testosterone applications in several disorders, with a special emphasis on prostatic carcinoma. The usefulness of salivary testosterone in the short-term (n = 4) and long-term (n = 13) follow-up of patients affected by prostatic carcinoma after medical or surgical orchiectomy has also been studied. Our results show a correlation (r = 0.62) between salivary and serum concentration values, as well as a significative decrease (p less than 0.001) in both quantities after treatment. Both these findings and the advantages inherent to the sampling obtaining, lead to the conclusion that salivary testosterone is a good alternative to serum testosterone.
