Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Completely diverting portacaval shunt (Eck's fistula) in dogs causes hepatocyte atrophy, disruption of hepatocyte organelles, fatty infiltration and low-grade hyperplasia. The effect of hepatic growth regulatory substances on these changes was assessed by constantly infusing test substances for four postoperative days after Eck's fistula into the detached left protal vein above the shunt. The directly infused left lobes were compared histopathologically with the untreated right lobes. In what has been called an hepatotrophic effect, stimulatory substances prevented the atrophy and increased hepatocyte mitoses. Of the hormones tested, only insulin was strongly hepatotrophic; T3 had a minor effect, and glucagon, prolactin, angiotensin II, vasopressin, norepinephrine and estradiol were inert. Insulin-like growth factor, hepatic stimulatory substance, transforming growth factor-alpha and hepatocyte growth factor (also known as hematopoietin A) were powerfully hepatotrophic, but epidermal growth factor had a barely discernible effect. Transforming growth factor-beta was inhibitory, but tamoxifen, interleukin-1 and interleukin-2 had no effect. The hepatotrophic action of insulin was not altered when the insulin infusate was mixed with transforming growth factor-beta or tamoxifen. These experiments show the importance of in vivo in addition to in vitro testing of putative growth control factors. They illustrate how Eck's fistula model can be used to screen for such substances and possibly to help delineate their mechanisms of action.
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PMID:Screening for candidate hepatic growth factors by selective portal infusion after canine Eck's fistula. 191 68

Although the ability of hormones and growth factors to stimulate DNA synthesis in rat hepatocytes has been investigated extensively, no such study of human hepatocytes has been reported. Here we describe a series of experiments to identify those factors that regulate human hepatocyte DNA synthesis in vitro and which therefore may play a role in the control of human liver regeneration. Human hepatocytes were isolated from normal liver tissue obtained after graft reduction for transplantation into pediatric recipients. Cells were maintained in culture for up to 5 days, and DNA synthesis was determined. Hydroxyurea reduced [3H]thymidine incorporation into DNA by 95%, indicating replicative DNA synthesis. As previously found with rat hepatocytes, epidermal growth factor and transforming growth factor-alpha stimulated DNA synthesis at low nanomolar concentrations; transforming growth factor-alpha was slightly more potent. Although the overall rate of thymidine incorporation was lower than that for rodent cells, human hepatocytes were sensitive to lower concentrations of these growth factors, and the degree of stimulation was similar. Conversely, transforming growth factor-beta inhibited DNA synthesis at low picomolar levels. By contrast (unlike rat hepatocytes), arginine-vasopressin failed to initiate or potentiate DNA synthesis in human cells. These data indicate that normal human hepatocytes can respond to low concentrations of growth promoters or inhibitors, previously shown to have activity on rat hepatocytes. These factors may then play a role in control of human liver growth. However, important species differences are apparent, highlighting the limitations of extrapolating from animal studies to humans.
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PMID:Growth of normal human hepatocytes in primary culture: effect of hormones and growth factors on DNA synthesis. 195 57

Ascitic fluid form ovarian cancer patients (n = 16), but not from patients with other cancers or with benign diseases, contains a growth-promoting activity which induces the proliferation of both fresh ovarian cancer cells (n = 5) and the ovarian cancer cell line HEY. The ascitic fluid growth factor(s) appears to signal cells through binding and activation of specific, saturable, high-affinity cell surface receptors. Incubation of fresh or cultured ovarian cancer cells with a partially purified preparation of ascitic fluid stimulates phosphatidylinositol turnover and increases cytosolic-free calcium. Each of these biochemical events has been implicated in the action of growth factors. Purified preparations of previously identified growth factors including epidermal growth factor, transforming growth factor-beta, tumor necrosis factor, platelet-derived growth factor, thrombin, insulin, interleukin-1, interleukin-2, vasopressin, angiotensin, alpha- and gamma-interferons, and fibroblast growth factor did not increase cytosolic-free calcium in either fresh ovarian cancer cells or HEY cells. Therefore, ascitic fluid appears to contain one or more previously unidentified growth factors which activate ovarian cancer cells through phosphatidylinositol hydrolysis and resultant changes in cytosolic-free calcium.
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PMID:A putative new growth factor in ascitic fluid from ovarian cancer patients: identification, characterization, and mechanism of action. 342 89

It is now largely established that the immune and neuroendocrine systems cross-talk by using similar ligands and receptors. In this context, the thymus-hypothalamus/pituitary axis can be regarded as a paradigm of connectivity in both normal and pathological conditions. For example, cytokines and thymic hormones modulate hypothalamic-pituitary functions: (a) interleukin (IL)-1 seems to upregulate the production of corticotropin-releasing factor and by adrenocorticotropin by hypothalamic neurons and pituitary cells, respectively; (b) thymulin enhances LH secretion. Conversely, a great deal of data strongly indicate that the hypothalamic-pituitary axis plays a role in the control of thymus physiology. Growth hormone (GH) for example, enhances thymulin secretion by thymic epithelial cells (TEC), both in vivo and in vitro, also increasing extracellular matrix-mediated TEC/thymocyte interactions. Additionally, gap junction-mediated cell coupling among TEC is upregulated by ACTH. In a second vein, it was shown that GH injections in aging mice increased total thymocyte numbers and the percentage of CD3-bearing cells, as well concanavalin-A mitogenic response and IL-6 production. In addition to mutual effects, thymus-pituitary similarities for cytokine and hormone production have been demonstrated. Cytokines such as IL-1, IL-2, IL-6, interferon-gamma, transforming growth factor-beta and others can be produced by hypothalamic and/or pituitary cells. Conversely, hormones including GH, PRL, LH, oxytocin, vasopressin and somatostatin can be produced intrathymically. Moreover, receptors for various cytokines and hormones are expressed in both the thymus and the hypothalamus/pituitary axis. Lastly, it is noteworthy that a thymus-pituitary connectivity can also be seen under pathological situations. In this regard, an altered HPA axis has been reported in AIDS, human falciparum malaria and murine rabies, that also show a severe thymic atrophy.
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PMID:Immunoneuroendocrine connectivity: the paradigm of the thymus-hypothalamus/pituitary axis. 987 43

The tissue kallikrein-kinin system is important in regulating cardiovascular and renal function, and dysregulation of the system has been implicated in heart and kidney pathologies. These findings suggest that if balance can be restored to the kallikrein-kinin axis, then associated disease progression may be attenuated. To test this hypothesis, recombinant adeno-associated virus (rAAV)-mediated human tissue kallikrein (HK) expression was induced in a rodent model of chronic renal failure involving 5/6 nephrectomy (nephrectomy plus 70% reduction of remaining kidney). rAAV-HK treatment attenuated the rise in blood pressure, glomerular sclerosis, and tubulointerstitial injury observed in this model. rAAV-HK treatment also attenuated renal function decline as measured by urinary microalbumin, osmolarity, and cGMP levels. Reverse transcriptase-polymerase chain reaction analysis showed that rAAV-HK-treated rats had higher levels of bradykinin receptor-2 (B(2)R) and dopamine receptor-1 mRNAs. In contrast, angiotensin II receptor-1, endothelin receptor-A, and vasopressin receptor-2 mRNAs were markedly downregulated in kidneys from HK-treated rats. Bradykinin induced similar changes in receptor levels and prevented transforming growth factor-beta(1)-induced tubulointerstitial fibrosis. The effects of bradykinin could be reversed with the B(2)R antagonist HOE-140. Together, these findings suggest that restoration of the kallikrein-kinin system reduces kidney injury and protects renal function in 5/6-nephrectomized rats via changes in the expression and activation of G protein-coupled receptors including B(2)R.
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PMID:Delivery of recombinant adeno-associated virus-mediated human tissue kallikrein for therapy of chronic renal failure in rats. 1840 47