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Updated: Aug 15, 2026

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
[Diurnal rhythm of endogenous somatostatin in patients with carcinoid]
S Kinová1, E Kovácová, E Kratochvíĺová
1I. interná klinika LF UK, Bratislava Nemocnica Ministerstva unútra SR, Bratislava.
Aim Of The Study:
Was to investigate the differences of the circadian rhythm of the endogenous somatostatin in patients with carcinoid and in healthy probands.
Methods:
The group of 30 patients (16 men/14 women) was divided onto two groups. The group M of 20 (12/8) pts with metastatic disease and group B of 10 pts without known metastases at the time of investigation. The control group A included by 12 healthy probands (7/5). Plasma levels of somatostatin were determined by radioimmunoassay. Fisher periodogram and Halberg's cosinor were used for statistical evaluation.
Results:
We confirmed the 24-hour circadian rhythm of somatostatin in group A, B and M. Patients of the M group when compared with A and B groups had higher mesor and the later 24-hour acrophase (p < 0.05) and 12-hour acrophase (p < 0.05). Treatment with lanreotide led to the significant decrease of the somatostatin mesor (p < 0.05).
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