vasoactive-intestinal-peptide and Hyperplasia

Topics: Acute Kidney Injury; Adenoma, Islet Cell; Adolescent; Adult; Aged; Carcinoid Tumor; Child; Dehydration; Female; Gastric Inhibitory Polypeptide; Gastrins; Gastrointestinal Hormones; Gastrointestinal Neoplasms; Glucagon; Humans; Hyperplasia; Hypokalemia; Insulin; Insulin Secretion; Male; Middle Aged; Pancreatic Neoplasms; Paraneoplastic Endocrine Syndromes; Precancerous Conditions; Serotonin; Somatostatin; Syndrome; Vasoactive Intestinal Peptide; Zollinger-Ellison Syndrome

We have shown that pituitary vasoactive intestinal peptide (VIP) mediates the effects of estrogen on lactotrope hyperplasia, angiogenesis and hyperprolactinemia, and reduces the pituitary content of transforming growth factor beta beta1 (TGF-beta1, an inhibitor of lactotrope proliferation). Dopamine agonists reverse lactotrope hyperplasia and hyperprolactinemia and also reduce the pituitary VIP content in hyperestrogenized rats. To elucidate the interaction of bromocriptine (BC) and pituitary VIP, a VIP receptor antagonist (VA), BC, or both drugs were administered for 5 days to F344 rats treated with diethylstilbestrol (DES). Both BC and VA similarly blocked the effects of DES on pituitary weight and pituitary content of prolactin (PRL), proliferating cell nuclear antigen, and vascular endothelial growth factor, without evidence of synergism. The estrogen effect on pituitary TGF-beta1 was completely inhibited by VA, but only partially by BC. On the contrary, serum PRL was close to the normal levels in the BC group 2 h after the first dose, while VA only reduced serum PRL after 5 days. DES increased VIP and VIP mRNA levels specifically at the pituitary, this effect being partially blocked by BC. These data suggest that the dopamine agonists inhibit lactotrope proliferation and angiogenesis by blocking the autocrine/paracrine action of VIP. On the other hand, the dopamine agonists inhibit the estrogen-induced hyperprolactinemia by acting through different pathways than those implicated in the proliferative process.

Topics: Animals; Blotting, Northern; Blotting, Western; Brain; Bromocriptine; Diethylstilbestrol; Dopamine; Dopamine Agonists; Estrogens, Non-Steroidal; Female; Hyperplasia; Pituitary Gland; Prolactin; Rats; Rats, Inbred F344; Receptors, Vasoactive Intestinal Peptide; RNA, Messenger; Transforming Growth Factor beta; Vascular Endothelial Growth Factor A; Vasoactive Intestinal Peptide

Vasoactive intestinal polypeptide (VIP) content is increased in the hyperplastic pituitaries of estrogen (E)-treated rats, thus suggesting that this neuropeptide could mediate the E effect on lactotrophs. E also decreases pituitary TGF-beta1 content, an autocrine/paracrine inhibitor of lactotroph proliferation, and induces pituitary angiogenesis. To elucidate the role of VIP in this context, lactotroph hyperplasia was induced in female Fisher 344 rats by implanting sc pellets of diethylstilbestrol (DES). Twenty-five days later, the rats were treated with three different increasing doses of a VIP receptor antagonist or the vehicle for 5 d. DES treatment resulted in a marked increase of serum prolactin (PRL), pituitary PRL content, PRL mRNA expression, pituitary weight, and pituitary proliferating cell nuclear antigen. DES treatment also increased pituitary VIP content and VIP mRNA levels, but not in the hypothalamus and cerebral cortex. Simultaneously, DES treatment decreased the pituitary TGF-beta1 content and increased the pituitary content of vascular endothelial growth factor. VIP receptor antagonist partially reverted the effect of DES on serum PRL and pituitary PRL, proliferating cell nuclear antigen, TGF-beta1, and vascular endothelial growth factor contents, as well as on pituitary weight, in a dose-dependent relation. These data suggest that pituitary VIP mediates the effect of E on lactotroph hyperplasia, pituitary TGF-beta1, and angiogenesis.

Topics: Animals; Autocrine Communication; Cerebral Cortex; Diethylstilbestrol; Endothelial Growth Factors; Estrogens, Non-Steroidal; Female; Hyperplasia; Hypothalamus; Intercellular Signaling Peptides and Proteins; Lymphokines; Organ Size; Paracrine Communication; Pituitary Gland; Pituitary Gland, Anterior; Prolactin; Proliferating Cell Nuclear Antigen; Rats; Rats, Inbred F344; RNA, Messenger; Transforming Growth Factor beta; Transforming Growth Factor beta1; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors; Vasoactive Intestinal Peptide

The histopathology of Fibrocalculous Pancreatic Diabetes (FCPD) has been extensively studied, but there are no reports on alteration in patterns of hormone secreting cells using immunohistochemistry in islets of FCPD patients. In this study, we report on the histopathology and immunohistochemistry of islets of FCPD patients and its possible correlation with the clinical picture. Pancreatic biopsies were carried out in six patients with FCPD at the time of surgery for abdominal pain. Routine histopathology and immunohistochemistry studies were carried out with six primary antibodies namely insulin, glucagon, pancreatic polypeptide (PP), somatostatin, vasoactive intestinal peptide and gastrin. Histopathology of the pancreas showed a spectrum of changes ranging from moderate to severe atrophy, fibrosis of the parenchyma and degeneration of the ducts. Nesidioblastosis was present in three patients. Immunohistochemical studies showed a decrease in the number of islets but some patients showed evidence of hyperplasia. There was an overall decrease in the percent of insulin cells and the positivity in the islets correlated with plasma C-peptide levels and the duration of diabetes. There was no consistent relationship with glucagon with some patients showing increased and other decreased positivity. There was a marked decrease in PP and somatostatin positivity, the significance of which is not clear. The reduction, but partial preservation of insulin positivity is consistent with the ketosis resistance shown by patients with Fibrocalculous Pancreatic Diabetes.

Topics: Adolescent; Adult; Atrophy; Biopsy; Blood Glucose; Chronic Disease; Diabetes Mellitus; Female; Gastrins; Glucagon; Humans; Hyperplasia; Immunohistochemistry; Insulin; Islets of Langerhans; Male; Middle Aged; Pancreas; Pancreatic Ducts; Pancreatic Polypeptide; Pancreatitis; Vasoactive Intestinal Peptide

The innervation of the human adrenal gland and of cortical lesions was studied in sections of cortical tissue (n=10), hyperplastic cortical tissue (n=3), and tissue from cortical adenomas (n=5) and carcinomas (n=6). The presence and distribution of nerve structures containing neuronal markers indicating sympathetic and parasympathetic innervation were studied by immunohistochemistry and the co-existence and co-localization patterns of the different markers by immunofluorescence. The cortex and hyperplastic cortical tissue had a moderate to rich supply of nerve structures containing the typical neuronal markers: protein gene product 9.5 (PGP 9.5), neuron-specific enolase (NSE), small vesicle synaptic protein type 2 (SV2), and nerves showing immunoreactivity to the adrenergic marker tyrosine hydroxylase (TH). All these immunoreactive nerves were located predominantly adjacent to blood vessels, but also among parenchymal cells. The cortex showed numerous nerve structures containing the neuropeptide substance P (SP), neuropeptide Y (NPY) and vasoactive intestinal protein (VIP), but few nerves containing these peptides were seen in hyperplastic cortical tissue. Typical markers were occasionally observed in cortical adenomas but were not found in carcinomas, except in a few cases where PGP 9.5 and NSE were present, but only adjacent to necrotic areas. Nerves containing NPY and VIP occurred in varying numbers in both adenomas and carcinomas. NPY- and VIP-immunoreactive nerve structures were seen mostly alongside blood vessels. There were several types of co-existence. For instance, NSE/VIP-, TH/VIP- and TH/NPY-immunoreactive nerve structures were often seen in the same trunk, but were only partly co-localized.

Topics: Adenoma; Adrenal Cortex; Adrenal Cortex Neoplasms; Carcinoma; Fluorescent Antibody Technique, Indirect; Humans; Hyperplasia; Immunoenzyme Techniques; Membrane Glycoproteins; Nerve Tissue Proteins; Neuropeptide Y; Parasympathetic Nervous System; Phosphopyruvate Hydratase; Sympathetic Nervous System; Thiolester Hydrolases; Tyrosine 3-Monooxygenase; Ubiquitin Thiolesterase; Vasoactive Intestinal Peptide

Hyperplasia of vascular smooth muscle cells (VSMCs) occurs during HIV infection, part of a spectrum of HIV-mediated cardiovascular and microvascular pathologies. These changes are not due to direct viral infection but may involve the receptor-mediated action of viral proteins, such as the envelope protein gp120. We sought to identify gp120 receptors which might mediate the vascular smooth muscle cell hyperplasia present in HIV infection. A homology between neuropeptide Y (NPY) and the previously identified receptor-active V2-region of gp120 defined by an octapeptide sequence (Peptide T) related to VIP was noted. Since NPY is mitogenic for VSMCs we therefore determined whether gp120 shares this activity. Rat aortic VSMCs were treated for 24 h with human (h)NPY and gp120 in the presence of 0.5% serum to measure [3H]thymidine incorporation, an index of cell proliferation. NPY increased [3H]thymidine incorporation by 80% after a 24-h treatment in a bimodal fashion, with peak effects at 10(-10) M and 10(-8) M. Gp120 was an even more potent mitogen for VSMCs with peak activity occurring at 10(-12) M. Peptide T was equipotent with gp120, and slightly less efficacious, suggesting that this domain may mediate gp120 effects on VSMCs. When combined, gp120 and NPY acted to antagonize one another, lowering DNA synthesis to basal levels. The profile of pharmacologic inhibition supports a role for NPY receptors since antagonists of Y1 and Y2 subtypes substantially or completely inhibited gp120-mediated VSMC proliferation. This is the first demonstration of the proliferative effects of HIV viral protein gp120 on VSMCs. The effect appears to be mediated via gp120 sequences related to VIP, peptide T, and NPY. These ligands may be competitive inhibitors of binding or gp120 processing. Novel treatments may emerge based upon VIP and NPY receptor antagonists if further work substantiates a role for gp120 in the vascular abnormalities of AIDS.

Topics: Amino Acid Sequence; Animals; Cardiovascular Diseases; Cell Division; Cells, Cultured; HIV; HIV Envelope Protein gp120; HIV Infections; Humans; Hyperplasia; Mitogens; Molecular Sequence Data; Muscle, Smooth, Vascular; Neuropeptide Y; Peptide T; Rats; Receptors, Neuropeptide Y; Sequence Homology, Amino Acid; Vasoactive Intestinal Peptide

Topics: Duodenal Neoplasms; Female; Ganglioneuroma; Growth Hormone; Humans; Hyperplasia; Immunohistochemistry; Infant; Jejunal Neoplasms; Pancreas; Pancreatic Neoplasms; Pancreatic Polypeptide; Vasoactive Intestinal Peptide

Colonic strictures are rare in patients who have cystic fibrosis, but recently have developed in those who have been treated with delayed-release high-dose pancreatic enzyme supplements. Colonic strictures from eight such pediatric patients showed neural abnormalities consisting of ganglion cell hyperplasia and ectopia, and intermyenteric plexus hyperplasia. Cholinergic and adrenergic stains of mucosal nerve fibers were more prominent in histological sections of the cystic fibrosis strictures than in sections from colons of children without cystic fibrosis. The mean grade of staining with acetylcholinesterase in the lamina propria of the strictured cystic fibrosis colons was 2.38 +/- 1.25, compared with .93 +/- .93 (P < .055) in bowels from children without cystic fibrosis. The mean grade for tyrosine hydroxylase staining in the lamina propria was 2 +/- .97 in the strictures and was .79 +/- .81 (P < .05) in the bowels of children who did not have cystic fibrosis. Vasoactive intestinal peptide staining in bowels from children with cystic fibrosis with and without stricture did not differ significantly from that of children without cystic fibrosis. Vasculopathy consisting of fibrointimal hyperplasia in submucosal veins and mesenteric arteries was found only in colonic strictures owing to cystic fibrosis. Colonic strictures in patients with cystic fibrosis who received high-dose pancreatic enzyme supplements contain ganglion cell abnormalities, and mucosal cholinergic and adrenergic activity may be increased in these strictures. The stricture vasculopathy may be drug-related and/or related to increased catecholamine activity.

Topics: Acetylcholinesterase; Adolescent; Adrenergic Fibers; Catecholamines; Child; Child, Preschool; Cholinergic Fibers; Choristoma; Colon; Colonic Diseases; Constriction, Pathologic; Cystic Fibrosis; Female; Ganglia; Humans; Hyperplasia; Infant, Newborn; Intestinal Mucosa; Male; Mesenteric Arteries; Pancreas; Pancreatic Extracts; Peripheral Nervous System Diseases; Tunica Intima; Tyrosine 3-Monooxygenase; Vascular Diseases; Vasoactive Intestinal Peptide

Irinotecan--or CPT-11; 7-ethyl-10-[4-(1-piperidino)-1-piperidino]-carbonyloxy-camptotheci n--is an inhibitor of DNA topoisomerase I and is clinically effective against several cancers. A major toxic effect of CPT-11 is severe diarrhea; however, the exact mechanism by which the drug induces diarrhea has not been established. Cisplatin (CDDP; cis-diamminedichloroplatinum) and CPT-11 exhibit synergistic antitumor activity and have been used in combination-chemotherapy regimens. Single-agent chemotherapy with conventional doses of CDDP does not cause clinically relevant diarrhea.. To elucidate the mechanisms of induction of diarrhea by high-dose CPT-11 and to compare them with those of diarrhea induced by high-dose CDDP, we used histopathologic and immunohistochemical methods to examine the intestines of mice treated with either CPT-11, CDDP, or saline (control).. Male ICR mice were administered intraperitoneally either 100 mg/kg CPT-11 daily for 4 days, 10 mg/kg CDDP daily for 3 days, or phosphate-buffered saline (control) daily for 4 days (10 mice per group). Preliminary experiments indicated that diarrhea was induced in mice approximately 6 days after administration of CPT-11 or CDDP; therefore, in the experiments described, animals were killed 6 days after the first dose. Serial paraffin-embedded sections of the intestine were stained with hematoxylin-eosin, Grimelius (to identify endocrine cells), or high-iron diamine-alcian blue (stains sialomucin blue and sulfomucin brown-black). Immunohistochemical analyses were performed with the use of anti-proliferating cell nuclear antigen (anti-PCNA; to assay proliferation), anti-Le(y) (BM-1; indirect measure of apoptosis), and anti-synaptophysin antibodies (to identify the enteric nervous system and enterochromaffin cells). A terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) method was used to detect DNA fragmentation in situ (i.e., apoptosis). The concentrations of two intestinally active secretogogues, plasma serotonin and vasoactive intestinal polypeptide, were also measured.. The levels of plasma intestinal hormones were similar in control, CPT-11, and CDDP groups. No active necrotic changes were observed in the intestines of CPT-11- and CDDP-treated mice, even though marked thinning of the intestinal walls was observed in both cases. The intestines of CPT-11-treated mice, but not those of control or CDDP-treated mice, were characterized by epithelial vacuolation of the ileum (associated with increased apoptosis as measured by BM-1 and TUNEL) and goblet-cell hyperplasia with excessive amount of sulfomucin in the cecum (suggesting induction of differentiation). By contrast, CDDP treatment of mice reduced the number of villi in the jejunum and destroyed crypt cells containing large Paneth (secretory) granules in the ileum.. CPT-11 may produce characteristic mucosal changes in the intestine by inducing apoptosis and cell differentiation. The observed changes are likely to cause malabsorption of water and electrolytes and hypersecretion of mucin. These structural and functional effects are probably the main causes of CPT-11-induced diarrhea. CDDP appears to cause diarrhea in mice by causing diffuse mucosal damage in the intestines.

Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Camptothecin; Cecum; Cisplatin; Diarrhea; Enzyme Inhibitors; Hyperplasia; Ileum; Intestinal Mucosa; Irinotecan; Male; Mice; Mucins; Proliferating Cell Nuclear Antigen; Serotonin; Topoisomerase I Inhibitors; Vasoactive Intestinal Peptide

The vasoactive intestinal peptide (VIP) immunoreactive nerve fibres in the gallbladder from 14 human patients with cholelithiasis was examined by immunohistochemical method. In the chronic cholecystitis, hyperplastic VIP immunoreactive nerves were observed around the hypertrophied muscle bundles, Rokitansky Aschoff Sinus and in the mucosal layer. However, in the acute cholecystitis and gangrenous cholecystitis, reduction or disappearance of VIP nerve fibres was observed. These reductions or disappearances of VIP immunoreactive nerves may secondly result from severe tissue damage. These results suggest that hyperplastic VIP nerves cause gallbladder relaxation, stasis and mucosal fluid unbalance, which may closely correlate to gallstone formation.

Topics: Adult; Aged; Aged, 80 and over; Cholecystitis; Cholelithiasis; Chronic Disease; Female; Gallbladder; Humans; Hyperplasia; Immunohistochemistry; Male; Middle Aged; Vasoactive Intestinal Peptide

The authors report a case of neuronal intestinal dysplasia in a 6-year-old girl. The disease is characterized by hyperplastic ganglia throughout the large and small intestine, associated with severe constipation. To better understand the pathophysiology of this disease the authors investigated the histopathologic, ultrastructural, and immunohistochemical characteristics of the intestinal tissue in this case. The hyperganglionosis was associated with immunohistochemical findings of intact expression of the neuropeptides controlling the peristaltic reflex, through lower expression of calcitonin-gene related peptide. With the recent progress in our understanding of the neural regulation of gastrointestinal function, it may now be possible to begin to understand the complex pathophysiological mechanisms underlying gastrointestinal motility disorders.

Topics: Calcitonin Gene-Related Peptide; Child; Colon; Constipation; Female; Gastrointestinal Motility; Humans; Hyperplasia; Intestinal Diseases; Myenteric Plexus; Submucous Plexus; Substance P; Vasoactive Intestinal Peptide

The goal of the present studies was to identify and characterize the site of secretin action in the liver. Sections of normal and bile duct-ligated rat livers were used for in vitro 125I-secretin receptor autoradiography. Saturable binding was observed in both normal and bile duct-ligated livers but was much greater in the bile duct-ligated preparations. Binding was limited to biliary epithelium and the increased secretin binding observed in the ligated livers correlated with the increase in ductular tissue. Saturable binding was inhibited in a dose-dependent fashion by increasing concentrations of nonradioactive secretin. Analysis of saturation binding showed that 125I-secretin binding was best fit by a one-site receptor model with a Kd of 5.3 +/- 1.1 nmol/L. Glucagon, vasoactive intestinal polypeptide, gastric inhibitory polypeptide, growth hormone-releasing hormone, and cholecystokinin did not inhibit saturable 125I-secretin binding at concentrations of 1 pmol/L to 1 mumol/L. The authors conclude that high-affinity, specific secretin binding sites are present in rat intrahepatic biliary epithelium. When bile ducts are stimulated to proliferate by bile duct ligation, secretin binding is also increased.

Topics: Animals; Autoradiography; Bile Ducts; Binding Sites; Binding, Competitive; Cholecystokinin; Dose-Response Relationship, Drug; Epithelium; Gastric Inhibitory Polypeptide; Glucagon; Growth Hormone-Releasing Hormone; Hyperplasia; Liver; Male; Rats; Rats, Inbred Strains; Receptors, G-Protein-Coupled; Receptors, Gastrointestinal Hormone; Secretin; Vasoactive Intestinal Peptide

The effects of vaso-active intestinal peptide (VIP) on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in Wistar rats given VIP every other day for 27 weeks after oral administration of MNNG for 25 weeks. In week 52, administration of VIP caused a significant increase in the incidence of gastric cancers, but did not influence their histological appearance. VIP significantly increased the labeling indices of the antral mucosa. Our findings indicate that VIP enhances gastric carcinogenesis, and that this effect may be related to its effect in increasing cell proliferation of the antral epithelial cells.

Topics: Animals; Drug Synergism; Gastric Juice; Gastrins; Hyperplasia; Male; Methylnitronitrosoguanidine; Rats; Rats, Inbred Strains; Stomach; Stomach Neoplasms; Vasoactive Intestinal Peptide

We have found vasoactive intestinal polypeptide (VIP)-, neurotensin-, substance P-, gastrin-releasing peptide-, calcitonin-, calcitonin gene related peptide (CGRP-2)-, and somatostatin-like immunoreactivities in extracts of sporadic human parathyroid adenomas (n = 18). The content of CGRP-2, substance P, and somatostatin in adenomas correlated directly with that of parathyroid hormone. In addition, concentrations of VIP versus substance P and somatostatin versus CGRP-2 in adenomas were directly correlated. Neuropeptide content of parathyroid hyperplasias differed from that of adenomas. VIP was detected in only one of seven parathyroid hyperplasias, and neurotensin was undetectable (0/7), whereas substance P was present in six of seven cases and GRP in five of seven hyperplasias. In hyperplasias, content of substance P correlated directly with that of gastrin-releasing peptide. Peroxidase immunohistochemistry localized VIP-like immunoreactivity to 20% to 50% of both chief and oxyphilic cells and rare clear cells and capillary endothelium in 11 of 12 adenomas studied. Focal staining was present in glandular epithelium of the rim of adjacent normal parathyroid tissue and in two of three normal parathyroid glands removed with thyroid goiters. This staining was both cytoplasmic and apical membrane. By contrast, in adenomas, neurotensin- and substance P-like positivities were confined to scattered (5% to 10%) oxyphilic cells. Cytoplasmic positivity for parathyroid hormone, noted in 30% to 70% of cells in serial sections, confirmed that these tissues were indeed parathyroid glands.

Topics: Adenoma; Calcitonin; Calcitonin Gene-Related Peptide; Gastrin-Releasing Peptide; Humans; Hyperplasia; Immunoenzyme Techniques; Neuropeptides; Neurotensin; Parathyroid Glands; Parathyroid Neoplasms; Peptides; Radioimmunoassay; Somatostatin; Substance P; Vasoactive Intestinal Peptide

Two patients with secretory diarrhea and signs and symptoms consistent with the Verner-Morrison syndrome and islet cell hyperplasia are described. Both patients responded well to subtotal pancreatectomies. The morphologic changes in the pancreata were characterized by proliferation of islets associated with periductal and interstitial fibrosis. Immunohistochemical stains demonstrated increased staining for serotonin in islet cells. A few islet cells also stained for vasoactive intestinal polypeptide. The significance of these results is discussed.

Topics: Adenoma, Islet Cell; Adult; Female; Histocytochemistry; Humans; Hyperplasia; Immunoenzyme Techniques; Islets of Langerhans; Male; Middle Aged; Pancreatic Neoplasms; Serotonin; Vasoactive Intestinal Peptide; Vipoma

Topics: Adenoma, Islet Cell; Adult; Female; Gastrins; Glucagon; Humans; Hyperplasia; Islets of Langerhans; Male; Middle Aged; Multiple Endocrine Neoplasia; Pancreatic Neoplasms; Pancreatic Polypeptide; Phosphopyruvate Hydratase; Serotonin; Somatostatin; Staining and Labeling; Vasoactive Intestinal Peptide; Zollinger-Ellison Syndrome

The case of an infant who developed refractory watery diarrhea at the age of 2 weeks is described. Diarrhea was secretory in type, stool weight on no oral intake was 400 to 600 gm daily. A vasoactive intestinal peptide (VIP)-producing tumor was suspected. At the age of 7 1/2 months an exploratory laparotomy revealed nonbeta islet cell hyperplasia of the pancreas. VIP levels were elevated in plasma and pancreatic tissue. After 95% pancreatectomy, plasma VIP level dropped to normal. Hypokalemia, described in adult patients with VIP-producing pancreatic tumors and refractory watery diarrhea, was not a significant problem in this infant. This is the first report on the association of refractory watery diarrhea with elevated levels of plasma VIP and pancreatic islet nonbeta cell hyperplasia in the pediatric age group.

Topics: Adenoma, Islet Cell; Chronic Disease; Diagnosis, Differential; Diarrhea, Infantile; Humans; Hyperplasia; Infant, Newborn; Infant, Newborn, Diseases; Islets of Langerhans; Male; Pancreatic Neoplasms; Vasoactive Intestinal Peptide