Disease relevance of Rifathyroin

• Decreased receptor binding of biologically inactive thyrotropin in central hypothyroidism. Effect of treatment with thyrotropin-releasing hormone [1].
• Tests with thyrotropin-releasing hormone were most useful in identifying patients with pituitary tumors [2].
• The beneficial effect of thyrotropin-releasing hormone in experimental spinal injury and its lack of effect on nociception indicate that it may have unique therapeutic potential in spinal trauma in human beings [3].
• CONCLUSIONS: In preterm infants at risk for lung disease, antenatal administration of thyrotropin-releasing hormone and glucocorticoid is no more beneficial than glucocorticoid alone [4].
• Seven patients with excessive growth (Group A) had hyperinsulinism, normal IGF values, elevated basal prolactin levels, and a delayed thyrotropin response to thyrotropin-releasing hormone, which was compatible with hypothalamic lesions [5].

Psychiatry related information on Rifathyroin

• To ascertain whether Huntington's chorea and schizophrenia are associated with specific regional alterations in neurotensin, somatostatin, and thyrotropin-releasing hormone, the concentrations of these putative neurotransmitters were measured by radioimmunoassay in postmortem brain samples from patients with Huntington's chorea or schizophrenia [6].
• Thyrotropin-releasing-hormone test in unipolar and bipolar depression [7].
• BACKGROUND: Therapeutic effects of the tripeptide protirelin (thyrotropin-releasing hormone) have been postulated in the affective disorders, but direct assessment in humans has been hindered by poor blood-brain barrier permeability [8].
• Endocrine, cardiovascular, and behavioral effects of intravenous protirelin in patients with panic disorder [9].
• We measured serum thyrotropin every 15 minutes during the night of sleep deprivation, thyrotropin bioactivity, the thyrotropin response to protirelin the next afternoon, and other indexes of hypothalamic-pituitary-thyroid function [10].

High impact information on Rifathyroin

• METHODS: We enrolled 996 women at 13 North American centers who were in preterm labor at <30 weeks' gestation in a double-blind, placebo-controlled, randomized trial of antenatal thyrotropin-releasing hormone, given intravenously in four doses of 400 microg each at eight-hour intervals [4].
• The finding of increasing fetal serum concentrations of thyroid-stimulating hormone in the presence of increasing thyroid hormone concentrations suggests that the sensitivity of the fetal pituitary gland to negative feedback is limited or is counterbalanced by increasing stimulation by thyrotropin-releasing hormone from the hypothalamus [11].
• The prolactin response to thyrotropin-releasing hormone differentiates isolated gonadotropin deficiency from delayed puberty [12].
• Neurologic recovery was significantly better after treatment with thyrotropin-releasing hormone than after saline or dexamethasone (P less than 0.01): at six weeks, the average animal given thyrotropin-releasing hormone was normal, whereas average control animals had marked spasticity [3].
• Adenohypophyseal degradation of thyrotropin releasing hormone regulated by thyroid hormones [13].

Chemical compound and disease context of Rifathyroin

• To determine whether thyroid hormone regulates the function of TRH in the hypothalamic tuberoinfundibular system, a study was made of the effect of hypothyroidism on thyrotropin-releasing hormone messenger RNA (proTRH mRNA) and TRH prohormone in the rat paraventricular nucleus [14].
• Intracisternal injection of ovine corticotropin-releasing factor (CRF) into the pylorus-ligated rat or the rat with gastric fistula resulted in a dose-dependent inhibition of gastric secretion stimulated with pentagastrin or thyrotropin-releasing hormone [15].
• If the clinical presentation was not characteristic of hyperthyroidism or if the FT3I was not elevated, a thyrotropin-releasing hormone (TRH) test was performed [16].
• Direct effects of thyrotropin-releasing hormone, cyproheptadine, and dopamine on adrenocorticotropin secretion from human corticotroph adenoma cells in vitro [17].
• Brain and spinal sites of action of the stable thyrotropin-releasing hormone (TRH) analogue, RX 77368 [pGlu-His-(3,3'-dimethyl)-Pro-NH2], for stimulation of gastric acid secretion have been investigated in urethane-anesthetized rats with gastric fistula [18].

Biological context of Rifathyroin

• The data presented here suggest that when GH3 cells are stimulated by thyrotropin-releasing hormone (TRH), an agonist inducing PtdIns(4,5)P2 hydrolysis, the two limbs of the inositol lipid signalling system interact to control free cytosolic calcium levels [( Ca2+]i) [19].
• When injected directly on the membrane of an excitable cell, thyrotropin-releasing hormone and 17 beta-estradiol induced action potentials within 1 minute [20].
• Thyrotropin-releasing hormone (TRH), however, causes a slow downregulation of TRH receptors (TRH-Rs), with a half-time of approximately 12 hours, in GH3 rat pituitary cells [21].
• When administered to the awake animal, thyrotropin-releasing hormone produced dose-dependent decreases in body temperature accompanied by behavioral quieting and reductions in metabolic rate and electromyographic activity [22].
• RXR-gamma, which is also expressed in skeletal muscle and the hypothalamus, may have a direct effect on muscle metabolism, regulation of food intake, or thyrotropin-releasing hormone levels in the hypothalamus [23].

Anatomical context of Rifathyroin

• Regulation of degradation of thyrotropin releasing hormone by thyroid hormones [24].
• We report here that thyrotropin-releasing hormone (TRH) acts within the CNS to elicit a vagus-dependent stimulation of gastric acid secretion [25].
• This report describes studies with nerve endings isolated from the rat hypothalamus in which dopamine at higher concentrations than those used previously has been found to stimulate the degradation of LH-RH but not thyrotropin releasing hormone (TRH) [26].
• Apart from the brain and spinal cord, immunoreactive thyrotropin-releasing hormone is found only in the blood and retina in significant concentrations [27].
• Thyrotropin-releasing hormone effects in the central nervous system: dependence on arousal state [22].

Associations of Rifathyroin with other chemical compounds

• Six of eight patients had impaired pituitary prolactin secretion after administration of thyrotropin-releasing hormone and chlorpromazine, with preservation of other anterior pituitary functions [28].
• The microiontophoretic application of thyrotropin-releasing hormone causes a selective reduction in neuronal excitation evoked by L-glutamate but not by acetylcholine in rat cerebral cortex [29].
• In two in vitro pituitary cell systems, vasopressin caused a specific and dose-related release of thyroid-stimulating hormone from cells that was equal in potency to that elicited by thyrotropin-releasing hormone, the primary acknowledged regulator of thyroid-stimulating hormone release [30].
• We hypothesize that the two peptides His-Pro DKP and thyrotropin-releasing hormone (TRH) have independent origins, since TRH is found in the B cells [31].
• TRH-IR in methanol extracts of both islets and culture medium was eluted in the same position as synthetic TRH by ion-exchange and gel chromatography and exhibited dilution curves parallel with synthetic TRH in radioimmunoassay [32].

Gene context of Rifathyroin

• Direct effects of catecholamines, thyrotropin-releasing hormone, and somatostatin on growth hormone and prolactin secretion from adenomatous and nonadenomatous human pituitary cells in culture [33].
• Receptors for thyrotropin-releasing hormone (TRH) are present on mouse pituitary thyrotropic tumor cells [34].
• Critical role for thyroid hormone receptor beta2 in the regulation of paraventricular thyrotropin-releasing hormone neurons [35].
• Regulation of human thyrotropin beta subunit gene (TSHB) expression by thyrotropin-releasing hormone (TRH) was examined in a clonal rat pituitary-cell line (GH3) [36].
• Overproduction of a Ca(2+)-independent protein kinase C isozyme, nPKC epsilon, increases the secretion of prolactin from thyrotropin-releasing hormone-stimulated rat pituitary GH4C1 cells [37].

Analytical, diagnostic and therapeutic context of Rifathyroin

• The effects of thyrotropin-releasing hormone and 17 beta-estradiol on the electrical membrane properties of a prolactin-secretin pituitary cell line (GH3/B6) were studied with intracellular microelectrode recordings [20].
• The ontogenesis of pancreatic thyrotropin-releasing hormone (TRH) in the human fetal gland was studied by radioimmunoassay or immunocytochemistry [38].
• [3H]Histidine was incorporated into a component that reacted with TRH antiserum and had the same retention time as synthetic TRH on reversed-phase high-performance liquid chromatography [32].
• The increase in secretion in response to thyrotropin-releasing hormone and bombesin was prevented by cervical vagotomy [39].
• Using the cell-attached patch-clamp technique, we studied the stimulation of single Ca2+ channels by thyrotropin-releasing hormone (TRH) in rat GH3 cells [40].

References