Abstract |
Two-hour incubations of human serum with 50 ng TRH or pyroglutamyl-histidyl-proline ( TRH-OH) were performed under substrate conditions of 0.2 microgram substrate/ml serum. During incubations with normal serum, 46.3 +/- 1.3 (SEM) ng TRH were degraded while only 14.2 +/- 5.1 ng TRH-OH were degraded (P less than 0.001). During incubations with serum from patients with hyperthyroidism, 42.7 +/- 2.6 ng TRH were degraded compared to only 19.6 +/- 2.0 ng TRH-OH (P less than 0.001). Despite the fact that TRH degradation was significantly greater than TRH-OH degradation in both normal and hyperthyroid serum, no formation of TRH-OH (less than 3.1 ng/incubation tube) from TRH was detected. Formation of TRH-OH from TRH was also not noted when normal or hyperthyroid serum was incubated with TRH at substrate concentrations of 62.5 microgram/ml serum. These data confirm other reports that TRH deamidation does not occur in normal serum and extends this observation to hyperthyroid serum.
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Authors | C H Emerson, A Mishal, H L Mahabeer, B L Currie |
Journal | The Journal of clinical endocrinology and metabolism
(J Clin Endocrinol Metab)
Vol. 49
Issue 1
Pg. 138-40
(Jul 1979)
ISSN: 0021-972X [Print] United States |
PMID | 109463
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- thyrotropin-releasing hormone, deamido-
- Thyrotropin-Releasing Hormone
- Pyrrolidonecarboxylic Acid
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Topics |
- Humans
- Hyperthyroidism
(blood)
- Pyrrolidonecarboxylic Acid
(analogs & derivatives)
- Thyrotropin-Releasing Hormone
(analogs & derivatives, metabolism)
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