Low TRH-TSH Responses in Human Essential Hypertension

Abstract

Thirty female and male essential hypertensive patients and eighteen normotensive controls were submitted to the TRH-TSH conventional test (200 ug intravenously, bolus injection of TRH). Supramaximal doses of 400 and 600 ug were repeated with a week interval to each subject. Hypertensives showed a significant lower response to both conventional and supramaximal TRH doses. Hypothalamic-pituitary-thyroid axis abnormalities, secondary to TRH-receptor alterations, could account for this result.

Thyrotropin-Releasing Hormone Receptor (TRHR) Gene Is Associated With Essential Hypertension

“…6,7 It was thus tempting to speculate that the component genes of the TRH system may be associated with essential hypertension. Because Lupi et al 9 reported that hypertensive patients have a blunted TSH response to TRH, indicating that there is a possible defect in the TRHR activation-mediated TSH release, we postulated that TRHR may be also involved in essential hypertension. Accordingly, we searched for molecular variants of the TRHR gene promoter.…”

“…Many endocrine disorders arise from mutations of these receptors, which result in changes of their basal or ligand-induced activity. 8 In this regard, Lupi et al 9 have demonstrated that hypertensive patients have a blunted TSH response to intravenous TRH bolus injection, suggesting a defect in the TRHR activationmediated TSH release. In summary, we postulated that the TRHR gene is involved in human hypertension.…”