RESUMO
Anatomical and physiological studies have described the cortex as a six-layer structure that receives, elaborates, and sends out information exclusively as excitatory output to cortical and subcortical regions. This concept has increasingly been challenged by several anatomical and functional studies that showed that direct inhibitory cortical outputs are also a common feature of the sensory and motor cortices. Similar to their excitatory counterparts, subsets of Somatostatin- and Parvalbumin-expressing neurons have been shown to innervate distal targets like the sensory and motor striatum and the contralateral cortex. However, no evidence of long-range VIP-expressing neurons, the third major class of GABAergic cortical inhibitory neurons, has been shown in such cortical regions. Here, using anatomical anterograde and retrograde viral tracing, we tested the hypothesis that VIP-expressing neurons of the mouse auditory and motor cortices can also send long-range projections to cortical and subcortical areas. We were able to demonstrate, for the first time, that VIP-expressing neurons of the auditory cortex can reach not only the contralateral auditory cortex and the ipsilateral striatum and amygdala, as shown for Somatostatin- and Parvalbumin-expressing long-range neurons, but also the medial geniculate body and both superior and inferior colliculus. We also demonstrate that VIP-expressing neurons of the motor cortex send long-range GABAergic projections to the dorsal striatum and contralateral cortex. Because of its presence in two such disparate cortical areas, this would suggest that the long-range VIP projection is likely a general feature of the cortex's network.
Assuntos
Córtex Auditivo/metabolismo , Vias Auditivas/metabolismo , Neurônios GABAérgicos/metabolismo , Córtex Motor/fisiologia , Peptídeo Intestinal Vasoativo/biossíntese , Animais , Córtex Auditivo/química , Vias Auditivas/química , Feminino , Neurônios GABAérgicos/química , Masculino , Camundongos , Camundongos Transgênicos , Técnicas de Cultura de ÓrgãosRESUMO
Vasoactive Intestinal Peptide (VIP) is the major physiological agonist of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) chloride channel activity. VIP functions as a neuromodulator and neurotransmitter secreted by neurons innervating all exocrine glands. VIP is also a potent vasodilator and bronchodilator that regulates exocrine gland secretions, contributing to local innate defense by stimulating the movement of water and chloride transport across intestinal and tracheobronchial epithelia. Previous human studies have shown that the rich intrinsic neuronal networks for VIP secretion around exocrine glands could be lost in tissues from patients with cystic fibrosis. Our research has since confirmed, in vitro and in vivo, the need for chronic VIP exposure to maintain functional CFTR chloride channels at the cell surface of airways and intestinal epithelium, as well as normal exocrine tissues morphology [1]. The goal of the present study was to examine changes in VIP in the lung, duodenum and sweat glands of 8- and 17-weeks old F508del/F508del mice and to investigate VIPergic innervation in the small intestine of CF mice, before important signs of the disease development. Our data show that a low amount of VIP is found in CF tissues prior to tissue damage. Moreover, we found a specific reduction in VIPergic and cholinergic innervation of the small intestine. The general innervation of the primary and secondary myenteric plexus was lost in CF tissues, with the presence of enlarged ganglionic cells in the tertiary layer. We propose that low amount of VIP in CF tissues is due to a reduction in VIPergic and cholinergic innervation and represents an early defect that constitutes an aggravating factor for CF disease progression.
Assuntos
Fibrose Cística/metabolismo , Duodeno/inervação , Duodeno/metabolismo , Pulmão/inervação , Pulmão/metabolismo , Glândulas Sudoríparas/inervação , Glândulas Sudoríparas/metabolismo , Peptídeo Intestinal Vasoativo/biossíntese , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
One of the urgent tasks of neuroscience is to understand how neuronal circuits operate, what makes them fail, and how to repair them when needed. Achieving this goal requires identifying the principal circuitry elements and their interactions with one another. However, what constitutes 'an atom' of a neuronal circuit, a neuronal type, is a complex question. In this review we focus on a class of cortical neurons that are exclusively identified by the expression of vasoactive intestinal polypeptide (VIP) and choline acetyltransferase (ChAT). The genetic profile of these VIP+ /ChAT+ interneurons suggests that they can release both γ-aminobutyric acid (GABA) and acetylcholine (ACh). This hints to a specific potential role in the cortical circuitry. Yet the VIP+ /ChAT+ interneurons are sparse (a mere 0.5% of the cortical neurons), which raises questions about their potential to significantly affect the circuit function. In view of recent developments in genetic techniques that allow for direct manipulation of these neurons, we provide a thorough and updated picture of the properties of the VIP+ /ChAT+ interneurons. We discuss their genetic profile, their physiological and structural properties, and their input-output mapping in sensory cortices and the medial prefrontal cortex (mPFC). Then, we examine possible amplification mechanisms for mediating their function in the cortical microcircuit. Finally, we discuss directions for further exploration of the VIP+ /ChAT+ population, focusing on its function during behavioral tasks as compared to the VIP+ /ChAT- population.
Assuntos
Córtex Cerebral/metabolismo , Colina O-Acetiltransferase/biossíntese , Colina O-Acetiltransferase/genética , Interneurônios/metabolismo , Peptídeo Intestinal Vasoativo/biossíntese , Peptídeo Intestinal Vasoativo/genética , Animais , Córtex Cerebral/química , Colina O-Acetiltransferase/análise , Humanos , Interneurônios/química , Transcriptoma/fisiologia , Peptídeo Intestinal Vasoativo/análiseRESUMO
PURPOSE: Vasoactive intestinal peptide (VIP) secreting tumor (VIPoma) constitutes a rare functional neuroendocrine tumor that most often originates from pancreatic islet cells and presents as a sporadic, solitary neoplasm of the pancreas. The purpose of this study was to systematically review the literature of pancreatic VIPomas and report clinicopathologic data and treatment modalities for this rare entity. METHODS: A systematic literature search was performed. The reviewed clinical series and case reports were included if they reported surgical treatment and also analyzed oncological outcomes on individual patients. Data extraction was performed using a standard registry pro-forma. RESULTS: The search resulted in 53 case reports and 2 case series including 65 patients in total. Median age reported was 54 years. The predominant pancreatic location was the pancreatic tail. The most common clinical symptom was watery diarrhea. Serum VIP levels were remarkably elevated in all patients. Distal pancreatectomy with or without splenectomy was the most commonly applied surgical procedure. Overall survival associated with pancreatic VIPoma was 67.7%, recurrence rate 40.4% and relevant median disease-free interval was 16 months. CONCLUSIONS: VIPomas are functional tumors that secrete excessive amounts of VIP. Clinically, production of VIP causes refractory watery diarrhea, hypokalemia and achlorydria. As far as diagnosis is concerned, elevated VIP plasma levels are required. Moreover, the majority of VIPomas are malignant or have already metastasized on diagnosis. Despite recent research on the therapeutic strategies against pancreatic VIPoma, surgical resection appears as the only potentially curative approach.
Assuntos
Recidiva Local de Neoplasia/cirurgia , Neoplasias Pancreáticas/cirurgia , Peptídeo Intestinal Vasoativo/biossíntese , Vipoma/cirurgia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Pancreatectomia , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Peptídeo Intestinal Vasoativo/sangue , Vipoma/sangue , Vipoma/patologia , Vipoma/terapiaRESUMO
Intrinsically photosensitive retinal ganglion cells (ipRGCs), which express the photopigment melanopsin, are photosensitive neurons in the retina and are essential for non-image-forming functions, circadian photoentrainment, and pupillary light reflexes. Five subtypes of ipRGCs (M1-M5) have been identified in mice. Although ipRGCs are spared in several forms of inherited blindness, they are affected in Alzheimer's disease and aging, which are associated with impaired circadian rhythms. Huntington's disease (HD) is an autosomal neurodegenerative disease caused by the expansion of a CAG repeat in the huntingtin gene. In addition to motor function impairment, HD mice also show impaired circadian rhythms and loss of ipRGC. Here, we found that, in HD mouse models (R6/2 and N171-82Q male mice), the expression of melanopsin was reduced before the onset of motor deficits. The expression of retinal T-box brain 2, a transcription factor essential for ipRGCs, was associated with the survival of ipRGCs. The number of M1 ipRGCs in R6/2 male mice was reduced due to apoptosis, whereas non-M1 ipRGCs were relatively resilient to HD progression. Most importantly, the reduced innervations of M1 ipRGCs, which was assessed by X-gal staining in R6/2-OPN4Lacz/+ male mice, contributed to the diminished light-induced c-fos and vasoactive intestinal peptide in the suprachiasmatic nuclei (SCN), which may explain the impaired circadian photoentrainment in HD mice. Collectively, our results show that M1 ipRGCs were susceptible to the toxicity caused by mutant Huntingtin. The resultant impairment of M1 ipRGCs contributed to the early degeneration of the ipRGC-SCN pathway and disrupted circadian regulation during HD progression.SIGNIFICANCE STATEMENT Circadian disruption is a common nonmotor symptom of Huntington's disease (HD). In addition to the molecular defects in the suprachiasmatic nuclei (SCN), the cause of circadian disruption in HD remains to be further explored. We hypothesized that ipRGCs, by integrating light input to the SCN, participate in the circadian regulation in HD mice. We report early reductions in melanopsin in two mouse models of HD, R6/2, and N171-82Q. Suppression of retinal T-box brain 2, a transcription factor essential for ipRGCs, by mutant Huntingtin might mediate the reduced number of ipRGCs. Importantly, M1 ipRGCs showed higher susceptibility than non-M1 ipRGCs in R6/2 mice. The resultant impairment of M1 ipRGCs contributed to the early degeneration of the ipRGC-SCN pathway and the circadian abnormality during HD progression.
Assuntos
Ritmo Circadiano/fisiologia , Doença de Huntington/patologia , Células Ganglionares da Retina/patologia , Animais , Modelos Animais de Doenças , Progressão da Doença , Proteínas do Olho/biossíntese , Genes Reporter , Doença de Huntington/genética , Doença de Huntington/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Atividade Motora , Reflexo Anormal , Reflexo Pupilar , Células Ganglionares da Retina/efeitos da radiação , Opsinas de Bastonetes/biossíntese , Núcleo Supraquiasmático/metabolismo , Proteínas com Domínio T/biossíntese , Peptídeo Intestinal Vasoativo/biossínteseRESUMO
BACKGROUND: Mast cells (MCs) and vasoactive intestinal polypeptide (VIP) have been proposed as regulators of the intestinal barrier and inflammation. Our aim was to map the distribution in inflammatory bowel disease (IBD) and murine colitis. METHODS: MCs, VIP, and VIP-receptors (VPACs) were quantified by immunofluorescence and enzyme-immunoassay (EIA) in ileal tissues (villus epithelium (VE) and adjacent VE, ie, VE next to the follicle-associated epithelium, (FAE)) from Crohn's disease (CD; n = 16) and non-IBD patients, and in colonic specimens of ulcerative colitis (UC; n = 12) and healthy controls (HCs). In addition, VIP levels were measured in plasma from HCs, non-IBD, and IBD in remission (CD n = 30; UC n = 30). Colon, ileum, and plasma from mice with dextran sulfate sodium (DSS)-induced colitis and control mice were analyzed likewise. KEY RESULTS: FAE-adjacent VE in ileum of CD possessed more MCs (P < 0.05) and MCs expressing VPAC1 (P < 0.05), but not VPAC2, compared to controls. Both adjacent and regular VE of CD had more MCs co-localizing/in close proximity to VIP (P < 0.05). In UC colon, more MCs (P < 0.0005), MCs close to VIP (P < 0.0005), and MCs expressing VPAC1 (P < 0.05) were found compared to controls. VIP levels were elevated in plasma from CD and UC compared to controls (P < 0.0005). Colon of DSS mice showed more MCs and MCs close to VIP (P < 0.05) compared to control mice. In vitro experiments revealed MCs expressing VPACs and internalized VIP after 120 minutes of VIP-stimulation. CONCLUSIONS AND INFERENCES: Communication between MCs and VIP is upregulated during IBD and mice colitis. In CD patients, the epithelium next to FAE seems to be more involved than the surrounding VE, suggesting increased MC-VIP-interactions in this intestinal region.
Assuntos
Colite Ulcerativa/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Mastócitos/metabolismo , Mastócitos/patologia , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo/biossíntese , Peptídeo Intestinal Vasoativo/biossíntese , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Contagem de Células , Colite Ulcerativa/induzido quimicamente , Doença de Crohn/metabolismo , Sulfato de Dextrana , Feminino , Humanos , Íleo/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo/genética , Regulação para Cima , Adulto JovemRESUMO
With the sequence of the vasoactive intestinal peptiepeptide (VIP) from humans and according to the condon bias of Pichia pastoris, we designed PCR primers of VIP and obtained the sequence of VIP by SOE-PCR. Then VIP gene was cloned into Pichia pastoris secretory expression vector and the cell secretary system GS115-pPICZαA-vip was constructed. The recombinant strain was induced by methanol for 96 hours, and we collected the supernatant and identified the VIP by mass spectrometry. The molecular weight of VIP was consistent with theoretical molecular weight. The final result showed that the target peptide VIP was successfully expressed. The experimental investigations of agarose gel diffusion revealed that the recombinant expression modified VIP had relatively strong antibacterial activity to E. coli ATCC25922 and S. aureus ATCC25923. The minimal inhibitory concentration (MIC) of VIP to E. coli ATCC25922 and S. aureus ATCC25923 was 8 mmol/L and 16 mmol/L. Further cytotoxicity and hemolytic experiments indicated that recombinant VIP was non-toxic to normal cells NCM460 and IPEC-J2, had little hemolysis activity to SD rat erythrocytes. Meanwhile, by transmission electron microscopy, we found that VIP mainly inhibited bacteria by disrupting the cell membrane. These experiments established a useful system for further studies, application and mass production of antimicrobial peptide VIP.
Assuntos
Peptídeos Catiônicos Antimicrobianos/biossíntese , Peptídeo Intestinal Vasoativo/biossíntese , Animais , Eritrócitos , Escherichia coli , Humanos , Pichia/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/biossíntese , Staphylococcus aureusRESUMO
Type 2 diabetes mellitus (T2DM) is characterised by insulin resistance, glucose intolerance and beta cell loss leading to hyperglycemia. Vasoactive intestinal peptide (VIP) has been regarded as a novel therapeutic agent for the treatment of T2DM because of its insulinotropic and anti-inflammatory properties. Despite these beneficial properties, VIP is extremely sensitive to peptidases (DPP-4) requiring constant infusion or multiple injections to observe any therapeutic benefit. Thus, we constructed an HIV-based lentiviral vector encoding human VIP (LentiVIP) to test the therapeutic efficacy of VIP peptide in a diet-induced obesity (DIO) animal model of T2DM. VIP gene expression was shown by immunocytochemistry (ICC) and VIP peptide secretion was confirmed by ELISA both in HepG2 liver and MIN6 pancreatic beta cell lines. Functional properties of VIP were demonstrated by cAMP production assay and glucose-stimulated insulin secretion test (GSIS). Intraperitoneal (IP) delivery of LentiVIP vectors into mice significantly increased serum VIP concentrations compared to control mice. Most importantly, LentiVIP delivery in DIO animal model of T2DM resulted in improved insulin sensitivity, glucose tolerance and protection against STZ-induced diabetes in addition to reduction in serum triglyceride/cholesterol levels. Collectively, these data suggest LentiVIP delivery should be evaluated as an experimental therapeutic approach for the treatment of T2DM.
Assuntos
Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 2/terapia , Peptídeo Intestinal Vasoativo/genética , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/prevenção & controle , Dieta Hiperlipídica , Modelos Animais de Doenças , Técnicas de Transferência de Genes , Glucose/metabolismo , Intolerância à Glucose , Células Hep G2 , Humanos , Insulina/metabolismo , Resistência à Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Lentivirus/genética , Lentivirus/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Peptídeo Intestinal Vasoativo/administração & dosagem , Peptídeo Intestinal Vasoativo/biossínteseAssuntos
Glucagon/biossíntese , Neoplasia Endócrina Múltipla Tipo 1/complicações , Tumores Neuroendócrinos/metabolismo , Neoplasias Pancreáticas/metabolismo , Peptídeo Intestinal Vasoativo/biossíntese , Idoso , Diabetes Mellitus Tipo 2/complicações , Humanos , Masculino , Tumores Neuroendócrinos/complicações , Tumores Neuroendócrinos/diagnóstico , Pancreatectomia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/diagnóstico , Esplenectomia , Resultado do TratamentoRESUMO
A 53-year-old man presented with diarrhoea and hypokalaemia and was diagnosed with a neuroendocrine tumour of unknown origin with multiple liver metastases. Somatostatin analogues led to a reduction in the size of the tumours and improvement of his symptoms. However, after several years, the tumours grew in size, and the patient's clinical symptoms recurred. The patient underwent transcatheter arterial embolization (TAE) of the hepatic artery to treat the liver metastases. Immediately after embolization, the symptoms disappeared. Although the patient had an unresectable vasoactive intestinal polypeptide-producing neuroendocrine tumour, the endocrine symptoms were able to be controlled with chemotherapy and TAE, resulting in a long-term survival.
Assuntos
Neoplasias Hepáticas/secundário , Tumores Neuroendócrinos/terapia , Neoplasias Pancreáticas/terapia , Peptídeo Intestinal Vasoativo/biossíntese , Terapia Combinada , Embolização Terapêutica/métodos , Endossonografia , Artéria Hepática , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/patologia , Octreotida/uso terapêutico , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Tomografia Computadorizada por Raios XAssuntos
Carcinoma Ductal Pancreático/patologia , Neoplasias Primárias Múltiplas/patologia , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Idoso , Carcinoma Ductal Pancreático/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Neoplasias Primárias Múltiplas/metabolismo , Tumores Neuroendócrinos/metabolismo , Neoplasias Pancreáticas/metabolismo , Peptídeo Intestinal Vasoativo/biossínteseRESUMO
Visual processing in the retina depends on coordinated signaling by interneurons. Photoreceptor signals are relayed to â¼20 ganglion cell types through a dozen excitatory bipolar interneurons, each responsive to light increments (ON) or decrements (OFF). ON and OFF bipolar cell pathways become tuned through specific connections with inhibitory interneurons: horizontal and amacrine cells. A major obstacle for understanding retinal circuitry is the unknown function of most of the â¼30-40 amacrine cell types, each of which synapses onto a subset of bipolar cell terminals, ganglion cell dendrites, and other amacrine cells. Here, we used a transgenic mouse line in which vasoactive intestinal polypeptide-expressing (VIP+) GABAergic interneurons express Cre recombinase. Targeted whole-cell recordings of fluorescently labeled VIP+ cells revealed three predominant types: wide-field bistratified and narrow-field monostratified cells with somas in the inner nuclear layer (INL) and medium-field monostratified cells with somas in the ganglion cell layer (GCL). Bistratified INL cells integrated excitation and inhibition driven by both ON and OFF pathways with little spatial tuning. Narrow-field INL cells integrated excitation driven by the ON pathway and inhibition driven by both pathways, with pronounced hyperpolarizations at light offset. Monostratified GCL cells integrated excitation and inhibition driven by the ON pathway and showed center-surround spatial tuning. Optogenetic experiments showed that, collectively, VIP+ cells made strong connections with OFF δ, ON-OFF direction-selective, and W3 ganglion cells but weak, inconsistent connections with ON and OFF α cells. Revealing VIP+ cell morphologies, receptive fields and synaptic connections advances our understanding of their role in visual processing. SIGNIFICANCE STATEMENT: The retina is a model system for understanding nervous system function. At the first stage, rod and cone photoreceptors encode light and communicate with a complex network of interneurons. These interneurons drive the responses of ganglion cells, which form the optic nerve and transmit visual information to the brain. Presently, we lack information about many of the retina's inhibitory amacrine interneurons. In this study, we used genetically modified mice to study the light responses and intercellular connections of specific amacrine cell types. The results show diversity in the shape and function of the studied amacrine cells and elucidate their connections with specific types of ganglion cell. The findings advance our understanding of the cellular basis for retinal function.
Assuntos
Interneurônios/citologia , Interneurônios/fisiologia , Retina/citologia , Retina/fisiologia , Vias Visuais/citologia , Vias Visuais/fisiologia , Animais , Células Cultivadas , Feminino , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Optogenética , Técnicas de Patch-Clamp , Peptídeo Intestinal Vasoativo/biossínteseRESUMO
BACKGROUND: Rikkunshito is a traditional Japanese herbal medicine that is used to treat appetite loss associated with cancer and other disorders. The formulation contains various constituents that influence cell signaling, and rikkunshito may accordingly affect human homeostasis through multiple regulatory pathways, including those governed by the endocrine system. We investigated the actions of rikkunshito on catecholamine release from PC12 cells, an adrenal chromaffin cell line. METHODS: The actions of rikkunshito on PC12 cells were evaluated by measuring intracellular cAMP levels, tyrosine hydroxylase (TH) and vasoactive intestinal peptide (VIP) mRNA expression levels, and catecholamine levels in the culture medium. The transcriptional activation of VIP gene by rikkunshito was assessed by using a VIP promoter-driven reporter gene assay. RESULTS: Rikkunshito dose-dependently enhanced forskolin-induced elevations in cAMP in PC12 cells, and also increased the gene expression of TH and VIP. The transcriptional activation of VIP gene by rikkunshito was confirmed. Norepinephrine and dopamine secretion into the culture medium of PC12 cells were also dose-dependently augmented by rikkunshito and/or forskolin, but experiments with a protein kinase C (PKC) activator and a phosphodiesterase inhibitor revealed that the effects of rikkunshito were not simply due to the modulation of PKC or phosphodiesterase activity. CONCLUSIONS: These findings suggest that rikkunshito enhances the release of catecholamines by a novel mechanism involving cAMP.
Assuntos
Catecolaminas/metabolismo , Células Cromafins/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Animais , Células Cromafins/metabolismo , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Células PC12 , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/biossíntese , Tirosina 3-Mono-Oxigenase/genética , Peptídeo Intestinal Vasoativo/biossíntese , Peptídeo Intestinal Vasoativo/genéticaRESUMO
The substance P neurokinin 1 receptor (NK1R) regulates motility, secretion, inflammation and pain in the intestine. The distribution of the NK1R is a key determinant of the functional effects of substance P in the gut. Information regarding the distribution of NK1R in subtypes of mouse enteric neurons is lacking and is the focus of the present study. NK1R immunoreactivity (NK1R-IR) is examined in whole-mount preparations of the mouse distal colon by indirect immunofluorescence and confocal microscopy. The distribution of NK1R-IR within key functional neuronal subclasses was determined by using established neurochemical markers. NK1R-IR was expressed by a subpopulation of myenteric and submucosal neurons; it was mainly detected in large multipolar myenteric neurons and was colocalized with calcitonin gene-related peptide, neurofilament M, choline acetyltransferase and calretinin. The remaining NK1R-immunoreactive neurons were positive for nitric oxide synthase. NK1R was expressed by most of the submucosal neurons and was exclusively co-expressed with vasoactive intestinal peptide, with no overlap with choline acetyltransferase. Treatment with substance P resulted in the concentration-dependent internalisation of NK1R from the cell surface into endosome-like structures. Myenteric NK1R was mainly expressed by intrinsic primary afferent neurons, with minor expression by descending interneurons and inhibitory motor neurons. Submucosal NK1R was restricted to non-cholinergic secretomotor neurons. These findings highlight key differences in the neuronal distribution of NK1R-IR between the mouse, rat and guinea-pig, with important implications for the functional role of NK1R in regulating intestinal motility and secretion.
Assuntos
Colo/inervação , Sistema Nervoso Entérico/metabolismo , Receptores da Neurocinina-1/metabolismo , Substância P/metabolismo , Animais , Anticorpos/imunologia , Calbindina 2/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Colina O-Acetiltransferase/biossíntese , Colo/metabolismo , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Trato Gastrointestinal/inervação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neurofilamentos/metabolismo , Óxido Nítrico Sintase/metabolismo , Receptores da Neurocinina-1/biossíntese , Receptores da Neurocinina-1/imunologia , Peptídeo Intestinal Vasoativo/biossínteseRESUMO
BACKGROUND: Anticholinergic drugs or vidian neurectomy can alleviate the symptoms of allergic rhinitis. OBJECTIVE: To show that inhibition of the cholinergic nerve influences the balance of T-helper type 1 and 2 cells in allergic rhinitis mice. METHODS: Twenty-four mice were randomly allocated to 1 of 4 groups: control, model, model with ipratropium bromide treatment, and model with 6-hydroxydopamine treatment. Allergic model-treated mice were sensitized with ovalbumin. Evaluation of allergic symptoms was recorded according to a symptom score. Ovalbumin serum IgE was measured by enzyme-linked immunosorbent assay. Expression of interleukin-4, interferon-γ, forkhead box P3, substance P, and vasoactive intestinal peptides was detected by immunohistochemistry and imaging analysis. RESULTS: Symptoms in allergic mice were significantly alleviated by ipratropium bromide. Ovalbumin serum IgE and eosinophils of nasal mucosa were significantly decreased. Interleukin-4 expression level was significantly higher in the allergic model group than in the control group and significantly decreased by ipratropium bromide (P < .05). In contrast, the expression of forkhead box P3 was lower in the allergic model group than in the control group and increased with treatment by ipratropium bromide (P < .05). Conversely, interferon-γ expression was not changed by anticholinergic treatment in the nasal mucosa of allergic mice. Expression of substance P and vasoactive intestinal peptide was significantly increased in allergic mice and decreased by ipratropium bromide. Sympathetic denervation did not change the expression of interleukin-4, interferon-γ, forkhead box P3, substance P, and vasoactive intestinal peptide. CONCLUSION: inhibition of the cholinergic nerve not only alleviated symptoms of allergic rhinitis by inhibiting the impulse of the parasympathetic nerve but also modulated the T-helper type 2-predominant immune reaction, expression of neuropeptides, and related inflammation factors.
Assuntos
Antagonistas Colinérgicos/uso terapêutico , Rinite Alérgica Perene/tratamento farmacológico , Rinite Alérgica Perene/imunologia , Equilíbrio Th1-Th2/efeitos dos fármacos , Células Th2/imunologia , Adrenérgicos/farmacologia , Animais , Neurônios Colinérgicos/metabolismo , Modelos Animais de Doenças , Eosinófilos/imunologia , Feminino , Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/metabolismo , Expressão Gênica/efeitos dos fármacos , Imunoglobulina E/sangue , Interferon gama/biossíntese , Interferon gama/metabolismo , Interleucina-4/biossíntese , Interleucina-4/metabolismo , Ipratrópio/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Mucosa Nasal/imunologia , Ovalbumina/imunologia , Oxidopamina/farmacologia , Sistema Nervoso Parassimpático/metabolismo , Rinite Alérgica , Substância P/biossíntese , Substância P/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th2/efeitos dos fármacos , Peptídeo Intestinal Vasoativo/biossíntese , Peptídeo Intestinal Vasoativo/metabolismoRESUMO
OBJECTIVE: The parasympathetic transmitter vasoactive intestinal peptide (VIP) increases salivary gland blood flow and evokes protein secretion and, in some species, such as rats, a small fluid secretion. It interacts synergistically with muscarinics for protein and fluid output. Human salivary acini are supplied with VIP-containing nerves. We hypothesise that VIP and clozapine, acting together, evoke a volume of saliva greater than the sum of those induced by each drug given separately. It was further considered whether, in the current test situation, circulatory events influenced the magnitude of the secretory response. MATERIAL AND METHODS: Saliva from parotid glands deprived of their autonomic innervation, and saliva and blood from innervated submandibular glands were collected in adrenoceptor antagonist-pretreated pentobarbitone-anaesthetised rats. Initially, the individual and then the combined effects of intravenous doses of VIP and clozapine were established. RESULTS: The submandibular volume response to the combination was 2-3 times higher, while blood pressure and glandular blood flow did not differ from those to VIP alone. The synergism occurred independent of nerves as shown in denervated parotid glands. CONCLUSIONS: From the current preclinical data, we speculate that VIP of parasympathetic origin, by its synergistic interaction with clozapine, may contribute to the clozapine (muscarinic M1-receptor)-induced sialorrhoea in schizophrenics.
Assuntos
Antipsicóticos/efeitos adversos , Clozapina/efeitos adversos , Sialorreia/induzido quimicamente , Peptídeo Intestinal Vasoativo/fisiologia , Animais , Feminino , Sistema Nervoso Parassimpático/metabolismo , Glândula Parótida/efeitos dos fármacos , Glândula Parótida/metabolismo , Ratos , Ratos Sprague-Dawley , Glândula Submandibular/efeitos dos fármacos , Glândula Submandibular/metabolismo , Peptídeo Intestinal Vasoativo/biossínteseRESUMO
OBJECTIVE: To investigate and analyze the correlation between the c-fos protein expression and neuropeptide content in the lung of bronchial asthmatic rats. METHODS: Thirty-two (32) SD rats were randomly allocated into 4 groups of the normal control, the non-acute asthma, the acute asthma and the dexamethasone intervention. Immunohistochemistry was performed for histological observation, and substance P (SP) and vasoactive intestinal peptide (VIP) concentrations in the bronchoalveolar lavage fluid were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: SP concentration in the alveolar lavage of asthmatic rat was significantly higher than that in the normal control group (P < 0.0001), whereas VIP concentration was significantly lower (P < 0.0001). The optical density of c-fos protein in the lung tissues of groups of the non-acute asthma, the acute asthma and the dexamethasone intervention was positively correlated with SP concentration in the bronchoalveolar lavage fluid (r = 0.908, r = 0.967, r = 0.865), and negatively correlated with the VIP concentration in the alveolar lavage (r = -0.974, r = -0.949, r = -0.962). CONCLUSION: The c-fos protein expression and neuropeptide content in the lungs of asthmatic rats are related with asthma attacks.
Assuntos
Asma/metabolismo , Proteínas Proto-Oncogênicas c-fos/biossíntese , Substância P/biossíntese , Peptídeo Intestinal Vasoativo/biossíntese , Animais , Biomarcadores/análise , Líquido da Lavagem Broncoalveolar/química , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Imuno-Histoquímica , Masculino , Neuropeptídeos/análise , Neuropeptídeos/biossíntese , Proteínas Proto-Oncogênicas c-fos/análise , Ratos , Ratos Sprague-Dawley , Substância P/análise , Peptídeo Intestinal Vasoativo/análiseRESUMO
BACKGROUND: The involvement of vagal parasympathetic efferents in esophageal myenteric neurons in vagal inhibitory pathways to the lower esophageal sphincter (LES) is not clear. Thus, this study was performed to demonstrate morphologically the presence of vagal inhibitory pathways to the LES via esophageal neurons. METHODS: Fast Blue (FB) was injected into the LES of Wistar rats, and 3 days after injection, the animals were subjected to electrical stimulation of the vagus nerve. The esophagus was processed for immunohistochemistry for Fos that was an immediate-early gene as a marker of neuronal activity, nitric oxide synthase (NOS), vasoactive intestinal polypeptide (VIP) and choline acetyltransferase (ChAT). The immunoreactivities were then compared with the FB labeling in esophageal neurons. KEY RESULTS: Fast Blue-labeled neurons were observed within an esophageal area of 30 mm oral to the LES, with the highest frequency in the esophagus just above the LES. Most of the FB-labeled neurons were positive for NOS and VIP, but a few for ChAT. Following vagal-electrical stimulation, one fourth of the FB-labeled neurons presented nuclei expressing Fos and most of these Fos/FB neurons were NOS-positive. CONCLUSIONS & INFERENCES: A majority of the FB-labeled esophageal neurons appeared to be descending motor neurons innervating the LES. Moreover, the colocalization of VIP and NOS in most of the LES-projecting neurons suggests that VIP and NO released from these neurons induce LES relaxation, and the innervation of the vagal efferents to the LES-projecting esophageal neurons in the distal esophagus implies a vagal inhibitory pathway responsible for LES relaxation.
Assuntos
Esfíncter Esofágico Inferior/inervação , Esôfago/inervação , Neurônios Nitrérgicos/citologia , Nervo Vago/citologia , Amidinas/farmacologia , Animais , Colina O-Acetiltransferase/análise , Colina O-Acetiltransferase/biossíntese , Estimulação Elétrica , Corantes Fluorescentes/farmacologia , Imuno-Histoquímica , Masculino , Neurônios Motores/citologia , Neurônios Motores/metabolismo , Vias Neurais/citologia , Vias Neurais/metabolismo , Neurônios Eferentes/citologia , Neurônios Eferentes/metabolismo , Neurônios Nitrérgicos/metabolismo , Ratos , Ratos Wistar , Nervo Vago/metabolismo , Peptídeo Intestinal Vasoativo/análise , Peptídeo Intestinal Vasoativo/biossínteseRESUMO
Fertility of domestic roosters decreases at ≈ 50 wk of age. In a previous study on aging white leghorn roosters, low fertility was accompanied by low levels of both hypothalamic vasoactive intestinal peptide (VIP) and pituitary prolactin (PRL) mRNA expression; however, their role in aging broiler breeder rooster reproduction is still unclear. In this study we compared reproductive activities of young (35-wk-old) and aging (73-wk-old) broiler breeder roosters. Weekly semen volume; concentration and ejaculation grade; and concentrations of plasma testosterone, estradiol, and PRL were examined. Every other week, 10 roosters from each group were euthanized, their testes weighed, and hypothalamus and pituitary removed to determine mRNA expression of hypothalamic GnRH-I, pituitary FSH, pituitary LH, hypothalamic VIP, and pituitary PRL. Aging roosters had significantly lower testis weight and semen volume, sperm concentration, ejaculation grade and plasma testosterone and low hypothalamic GnRH-I, pituitary FSH, and pituitary LH mRNA expression than young roosters (P ≤ 0.05). Aging roosters had higher concentrations of plasma estradiol and PRL and higher hypothalamic VIP and pituitary PRL mRNA expression than young roosters (P ≤ 0.05). We suggest that PRL, which is known to inhibit the gonadal axis, and its releasing factor, VIP, play an important role in the reproductive failure associated with age in broiler breeder roosters.
Assuntos
Galinhas/fisiologia , Hipotálamo/fisiologia , Hipófise/fisiologia , Prolactina/sangue , Reprodução/fisiologia , Peptídeo Intestinal Vasoativo/sangue , Fatores Etários , Animais , Galinhas/sangue , Estradiol/sangue , Hormônio Foliculoestimulante/biossíntese , Hormônio Foliculoestimulante/genética , Hormônio Liberador de Gonadotropina/biossíntese , Hormônio Liberador de Gonadotropina/sangue , Hormônio Liberador de Gonadotropina/genética , Hipotálamo/metabolismo , Hormônio Luteinizante/biossíntese , Hormônio Luteinizante/sangue , Hormônio Luteinizante/genética , Masculino , Hipófise/metabolismo , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Sêmen/fisiologia , Neurônios Serotoninérgicos/fisiologia , Testículo/anatomia & histologia , Testículo/fisiologia , Testosterona/sangue , Peptídeo Intestinal Vasoativo/biossíntese , Peptídeo Intestinal Vasoativo/genéticaRESUMO
OBJETIVO: Avaliar a expressão de mediadores neurotróficos (NGF, NPY E VIP) e pró-inflamatórios (TNF-α) em fragmentos de reto e sigmoide comprometidos por endometriose. MÉTODOS: Foram selecionadas 24 pacientes submetidas ao tratamento cirúrgico de endometriose de reto e sigmoide com técnica de ressecção segmentar, seguido de anastomose mecânica término-terminal, com grampeador circular, no período de janeiro de 2005 a dezembro de 2007. Neste estudo incluímos mulheres no menacme que se submeteram a tratamento cirúrgico por endometriose profunda infiltrativa com acometimento do reto e sigmoide, atingindo o nível da camada muscular, submucosa ou mucosa. Para o grupo de estudo foram utilizados 24 fragmentos de reto e sigmoide com endometriose confirmada histologicamente, sendo um fragmento de cada uma das 24 pacientes selecionadas. Para o grupo controle, utilizou-se um fragmento da margem distal da ressecção, denominado anel de anastomose, de cada uma das 24 pacientes selecionadas e incluídas no estudo. As amostras foram agrupadas em blocos de Tissue Micro Array (TMA) e submetidas à reação imunoistoquímica para avaliar a expressão do fator de necrose tumoral alfa (TNF-α), do fator de crescimento neural (NGF), do neuropeptídeo Y (NPY) e do peptídeo intestinal vasoativo P (VIP), e posterior análise semiquantitativa da imunomarcação por meio da leitura da densidade ótica relativa (DO). RESULTADOS: Observou-se maior densidade ótica relativa da imunomarcação para TNF-α e NGF no grupo de estudo (amostras com endometriose intestinal), DO= 0,01, respectivamente, para as duas proteínas (p<0,05), em relação aos controles sem endometriose. Não houve diferença estatística na densidade ótica da imunomarcação do NPY e VIP. CONCLUSÃO: Identificou-se o aumento da imunomarcação dos anticorpos TNF-α e NGF em fragmentos de reto e sigmoide comprometidos por endometriose em relação aos controles livres da doença. Não identificamos diferença estatística na imunomarcação das proteínas NPY e VIP.
PURPOSE: To evaluate the expression of neurotrophic (NGF, NPY and VIP) and pro-inflammatory (TNF-α) mediators in the rectum and sigmoid fragments compromised by endometriosis. METHODS: Twenty-four patients were selected to undergo surgical treatment of endometriosis of the rectum and sigmoid colon with a segmental resection technique, followed by end-to-end anastomosis with a circular stapler from January 2005 to December 2007. The study included premenopausal women who underwent surgical treatment for deep endometriosis infiltrating the rectum with involvement of the rectum and sigmoid, reaching the level of the muscle layer, submucosa or mucosa. Twenty-four rectum and sigmoid fragments with histologically confirmed endometriosis, one from each of the 24 selected patients, were used for the study group. For the control group, we used a fragment of the distal resection margin called anastomosis ring from each of the 24 patients enrolled in the study. Samples were grouped into Tissue Micro Array (TMA) blocks and subjected to immunohistochemistry to evaluate the expression of tumor necrosis factor alpha (TNF-α), nerve growth factor (NGF), neuropeptide Y (NPY) and P vasoactive intestinal peptide (VIP), followed by semiquantitative analysis of immunostaining by reading the relative optical density (OD). RESULTS: There was higher optical density relative to TNF-α immunostaining and NGF in the study group (samples with intestinal endometriosis), DO=0.01, for the two proteins, respectively (p<0.05), compared to controls without endometriosis. There was no statistically significant difference in the optical density of immunostaining of NPY and VIP. CONCLUSION: We identified increased immunostaining of TNF-α antibodies and fragments of NGF in the rectum and sigmoid compromised by endometriosis compared to disease-free controls. We did not identify any statistical difference in immunostaining of NPY and VIP proteins.