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Updated: Sep 5, 2026

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
[Circadian rhythm of blood pressure and daily hormonal variations]
Insights
Severe hypertension in diabetics disrupts the normal blood pressure cycle, linked to lower cortisol and catecholamine levels. This suggests hormonal imbalances may play a role in cardiovascular complications.
Area of Science:
- Endocrinology
- Cardiovascular Medicine
- Diabetology
Abstract:
As the mortality rate due to cardiovascular complications has increased, knowing the importance of the diurnal cycle of blood pressure, ambulatory blood pressure was recorded in 50 noninsulin-dependent diabetics aged 45 to 65 years. The diurnal cycle of the serum levels of cortisol, prolactin and growth hormone were determined by RIA (radioimmunoassay) method and urinary catechlamines by radioenzymatic method. The obtained results showed significantly higher blood pressure values during sleeping periods in patients with severe hypertension and consequently significantly lower night/day ratio of cortisol and urinary catecholamines as well as increased prolactin. In diabetic patients with autonomic neuropathy blood pressure values were significantly higher during night, but without changes in regard to hormones. It can be concluded that glucocorticoid hormones and catecholamines might be associated with the control of diurnal cycle of blood pressure in patients with severe hypertension.
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