The thyrotropin-releasing hormone gene

Wilber, John F.; Feng, Peng; Li, Qiao Ling; Shi, Zhan

doi:10.1016/1043-2760(96)00022-7

Cited by 9 publications

(1 citation statement)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thyrotropin-releasing hormone (TRH) is present not only in the hypothalamic paraventricular nucleus (PVN) as the regulator of thyroid-stimulating hormone secretion, but is demonstrated ubiquitously throughout the extrahvpothalamic central nervous system (CNS), where TRH functions as a ncurotransmitteror ncuromodulator in the integration of CNS activities [1][2][3][4], TRH has been also identified in several extra-CNS loci [5][6][7], where its func tion is still unclear [8,9], Recently, our laboratory has reported that the TRH gene is expressed in the rat heart. TRH mRNA densities were five-fold higher in atria than in ventricles, whereas TRH-receptors were located pre dominantly in ventricles [5,10,11], Intracoronary admin istration of TRH in an open-chested dog model caused a significant increase in cardiac contractility [10,12,13].…”

Section: Introductionmentioning

confidence: 99%

Localization of Thyrotropin-Releasing Hormone mRNA Expression in the Rat Heart by in situ Hybridization Histochemistry

Shi¹,

Wen²,

Mergner

et al. 1996

Pathobiology

Self Cite

View full text Add to dashboard Cite

Our laboratory has recently detected mRNA of thyrotropin-releasing hormone (TRH) in the rat heart. The density of mRNA for TRH is five-fold higher in the atria than in the left and right ventricle. We also found TRH receptor mRNA and ³H-TRH-binding sites in both ventricles. Cardiac contractility was stimulated after intracoronary administration of TRH. This study was performed to investigate the localization of TRH in the heart. We utilized in situ hybridization histochemistry (ISHH) to localize TRH mRNA expression in the rat heart. ISHH was performed on fresh frozen heart tissue sections, which were hybridized with a specific ³⁵S-TRH oligo probe and subsequently processed by autoradiography. The autoradiographic signals corresponding to TRH mRNA were analyzed with an image program. For positive controls, TRH mRNA was identified in the hypothalamic paraventricular nucleus. This test confirms the specificity of the TRH oligo probe. Cardiac hybridization signals were observed predominantly in the atria and localized preferentially in atrial connective tissues, vascular adventitia and atrial cardiomyocytes. No hybridization signals were found in ventricular cardiomyocytes. These observations suggest that TRH is synthesized in atrial myocytes and atrial vascular structures. Based on studies which show synthesis of the TRH receptors in ventricular cardiomyocytes, we hypothesize that atrial TRH is an endocrine source for the stimulation of ventricular contractility and that endothelial and adventitial TRH may play a role(s) in the regulation of the growth and/or vasomotor tone of the cardiac vascular system.

show abstract