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McCosh RB, Lopez JA, Szeligo BM, Bedenbaugh MN, Hileman SM, Coolen LM, Lehman MN, Goodman RL. Evidence that Nitric Oxide Is Critical for LH Surge Generation in Female Sheep. Endocrinology 2020; 161:bqaa010. [PMID: 32067028 PMCID: PMC7060766 DOI: 10.1210/endocr/bqaa010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 01/31/2020] [Indexed: 12/14/2022]
Abstract
Elevated and sustained estradiol concentrations cause a gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) surge that is necessary for ovulation. In sheep, several different neural systems have been implicated in this stimulatory action of estradiol and this study focused on somatostatin (SST) neurons in the ventral lateral region of the ventral medial nucleus (vlVMN) which express c-Fos during the surge. First, we determined if increased activity of SST neurons could be related to elevated GnRH secretion by assessing SST synapses onto GnRH neurons and neurons coexpressing kisspeptin, neurokinin B, dynorphin (KNDy). We found that the percentage of preoptic area GnRH neurons that receive SST input increased during the surge compared with other phases of the cycle. However, since SST is generally inhibitory, and pharmacological manipulation of SST signaling did not alter the LH surge in sheep, we hypothesized that nitric oxide (NO) was also produced by these neurons to account for their activation during the surge. In support of this hypothesis we found that (1) the majority of SST cells in the vlVMN (>80%) contained neuronal nitric oxide synthase (nNOS); (2) the expression of c-Fos in dual-labeled SST-nNOS cells, but not in single-labeled cells, increased during the surge compared with other phases of the cycle; and (3) intracerebroventricular (ICV) infusion of the nitric oxide synthase inhibitor, N(G)-nitro-L-arginine methyl ester, completely blocked the estrogen-induced LH surge. These data support the hypothesis that the population of SST-nNOS cells in the vlVMN are a source of NO that is critical for the LH surge, and we propose that they are an important site of estradiol positive feedback in sheep.
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Affiliation(s)
- Richard B McCosh
- Department of Physiology and Pharmacology, West Virginia University Health Science Center, Morgantown, West Virginia
| | - Justin A Lopez
- Department of Physiology and Pharmacology, West Virginia University Health Science Center, Morgantown, West Virginia
| | - Brett M Szeligo
- Department of Physiology and Pharmacology, West Virginia University Health Science Center, Morgantown, West Virginia
| | - Michelle N Bedenbaugh
- Department of Physiology and Pharmacology, West Virginia University Health Science Center, Morgantown, West Virginia
| | - Stanley M Hileman
- Department of Physiology and Pharmacology, West Virginia University Health Science Center, Morgantown, West Virginia
| | - Lique M Coolen
- Brain Health Research Institute, Kent State University, Kent, Ohio
- Department of Biological Sciences, Kent State University, Kent, Ohio
| | - Michael N Lehman
- Brain Health Research Institute, Kent State University, Kent, Ohio
| | - Robert L Goodman
- Department of Physiology and Pharmacology, West Virginia University Health Science Center, Morgantown, West Virginia
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Neuronal Nitric Oxide Mediates the Anti-inflammatory Effects of Intestinal Ischemic Preconditioning. J Surg Res 2019; 244:241-250. [DOI: 10.1016/j.jss.2019.06.053] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 05/15/2019] [Accepted: 06/14/2019] [Indexed: 01/25/2023]
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Differentially expressed genes in the caecal and colonic mucosa of Landrace finishing pigs with high and low food conversion ratios. Sci Rep 2017; 7:14886. [PMID: 29097775 PMCID: PMC5668291 DOI: 10.1038/s41598-017-14568-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 09/08/2017] [Indexed: 02/08/2023] Open
Abstract
The feed conversion ratio (FCR) is an essential economic trait for pig production, and is directly related to feed efficiency. Studies identifying the differential expression of functional genes involved in biological and molecular mechanisms in the intestine in relation to growth performance are rare. In this study, RNA-Seq was used to identify transcriptomes in caecal and colonic mucosal tissues in order to determine the differential expression of genes from two full-sibling pairs and two half-sibling pairs of Landrace finishing pigs with opposing FCR phenotypes. In total, 138 (comparison of high and low FCR in caecal mucosa), 64 (comparison of high and low FCR in colonic mucosa), and 165 (contrast between the caecal and colonic mucosa) differentially expressed genes were identified. Some of these genes were functionally related to energy and lipid metabolism, particularly short chain fatty acids metabolism, as well as gastrointestinal peristalsis and ion transport. Functional annotation were performed to identify differentially expressed genes, such as GUCA2A, GUCA2B, HSP70.2, NOS2, PCK1, SLCs, and CYPs, which may positively influence feed efficiency in Landrace pigs. These differentially expressed genes need to be further tested for candidate genes that are related to feed efficiency.
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McQuade RM, Carbone SE, Stojanovska V, Rahman A, Gwynne RM, Robinson AM, Goodman CA, Bornstein JC, Nurgali K. Role of oxidative stress in oxaliplatin-induced enteric neuropathy and colonic dysmotility in mice. Br J Pharmacol 2016; 173:3502-3521. [PMID: 27714760 PMCID: PMC5120153 DOI: 10.1111/bph.13646] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 09/18/2016] [Accepted: 09/19/2016] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND AND PURPOSE Oxaliplatin is a platinum-based chemotherapeutic drug used as a first-line therapy for colorectal cancer. However, its use is associated with severe gastrointestinal side-effects resulting in dose limitations and/or cessation of treatment. In this study, we tested whether oxidative stress, caused by chronic oxaliplatin treatment, induces enteric neuronal damage and colonic dysmotility. EXPERIMENTAL APPROACH Oxaliplatin (3 mg·kg-1 per day) was administered in vivo to Balb/c mice intraperitoneally three times a week. The distal colon was collected at day 14 of treatment. Immunohistochemistry was performed in wholemount preparations of submucosal and myenteric ganglia. Neuromuscular transmission was studied by intracellular electrophysiology. Circular muscle tone was studied by force transducers. Colon propulsive activity studied in organ bath experiments and faeces were collected to measure water content. KEY RESULTS Chronic in vivo oxaliplatin treatment resulted in increased formation of reactive oxygen species (O2 -), nitration of proteins, mitochondrial membrane depolarisation resulting in the release of cytochrome c, loss of neurons, increased inducible NOS expression and apoptosis in both the submucosal and myenteric plexuses of the colon. Oxaliplatin treatment enhanced NO-mediated inhibitory junction potentials and altered the response of circular muscles to the NO donor, sodium nitroprusside. It also reduced the frequency of colonic migrating motor complexes and decreased circular muscle tone, effects reversed by the NO synthase inhibitor, Nω-Nitro-L-arginine. CONCLUSION AND IMPLICATIONS Our study is the first to provide evidence that oxidative stress is a key player in enteric neuropathy and colonic dysmotility leading to symptoms of chronic constipation observed in oxaliplatin-treated mice.
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Affiliation(s)
- Rachel M McQuade
- Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, Melbourne, Australia
| | - Simona E Carbone
- Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, Melbourne, Australia
| | - Vanesa Stojanovska
- Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, Melbourne, Australia
| | - Ahmed Rahman
- Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, Melbourne, Australia
| | - Rachel M Gwynne
- Department of Physiology, Melbourne University, Melbourne, Australia
| | - Ainsley M Robinson
- Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, Melbourne, Australia
| | - Craig A Goodman
- Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, Melbourne, Australia
| | - Joel C Bornstein
- Department of Physiology, Melbourne University, Melbourne, Australia
| | - Kulmira Nurgali
- Centre for Chronic Disease, College of Health and Biomedicine, Victoria University, Melbourne, Australia
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Gajęcka M, Sławuta P, Nicpoń J, Kołacz R, Kiełbowicz Z, Zielonka Ł, Dąbrowski M, Szweda W, Gajęcki M, Nicpoń J. Zearalenone and its metabolites in the tissues of female wild boars exposed per os to mycotoxins. Toxicon 2016; 114:1-12. [DOI: 10.1016/j.toxicon.2016.02.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 01/26/2016] [Accepted: 02/11/2016] [Indexed: 02/01/2023]
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Nolan JV, Godwin IR, de Raphélis-Soissan V, Hegarty RS. Managing the rumen to limit the incidence and severity of nitrite poisoning in nitrate-supplemented ruminants. ANIMAL PRODUCTION SCIENCE 2016. [DOI: 10.1071/an15324] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Inclusion of nitrate (NO3−) in ruminant diets is a means of increasing non-protein nitrogen intake while at the same time reducing emissions of enteric methane (CH4) and, in Australia, gaining carbon credits. Rumen microorganisms contain intracellular enzymes that use hydrogen (H2) released during fermentation to reduce NO3− to nitrite (NO2−), and then reduce the resulting NO2− to ammonia or gaseous intermediates such as nitrous oxide (N2O) and nitric oxide (NO). This diversion of H2 reduces CH4 formation in the rumen. If NO2− accumulates in the rumen, it may inhibit growth of methanogens and other microorganisms and this may further reduce CH4 production, but also lower feed digestibility. If NO2− is absorbed and enters red blood cells, methaemoglobin is formed and this lowers the oxygen-carrying capacity of the blood. Nitric oxide produced from absorbed NO2− reduces blood pressure, which, together with the effects of methaemoglobin, can, at times, lead to extreme hypoxia and death. Nitric oxide, which can be formed in the gut as well as in tissues, has a variety of physiological effects, e.g. it reduces primary rumen contractions and slows passage of digesta, potentially limiting feed intake. It is important to find management strategies that minimise the accumulation of NO2−; these include slowing the rate of presentation of NO3– to rumen microbes or increasing the rate of removal of NO2−, or both. The rate of reduction of NO3− to NO2− depends on the level of NO3− in feed and its ingestion rate, which is related to the animal’s feeding behaviour. After NO3− is ingested, its peak concentration in the rumen depends on its rate of solubilisation. Once in solution, NO3− is imported by bacteria and protozoa and quickly reduced to NO2−. One management option is to encapsulate the NO3− supplement to lower its solubility. Acclimating animals to NO3− is an established management strategy that appears to limit NO2− accumulation in the rumen by increasing microbial nitrite reductase activity more than nitrate reductase activity; however, it does not guarantee complete protection from NO2− poisoning. Adding concentrates into nitrate-containing diets also helps reduce the risk of poisoning and inclusion of microbial cultures with enhanced NO2−-reducing properties is another potential management option. A further possibility is to inhibit NO2− absorption. Animals differ in their tolerance to NO3− supplementation, so there may be opportunities for breeding animals more tolerant of dietary NO3−. Our review aims to integrate current knowledge of microbial processes responsible for accumulation of NO2− in rumen fluid and to identify management options that could minimise the risks of NO2− poisoning while reducing methane emissions and maintaining or enhancing livestock production.
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Zielonka Ł, Waśkiewicz A, Beszterda M, Kostecki M, Dąbrowski M, Obremski K, Goliński P, Gajęcki M. Zearalenone in the Intestinal Tissues of Immature Gilts Exposed per os to Mycotoxins. Toxins (Basel) 2015; 7:3210-23. [PMID: 26295259 PMCID: PMC4549746 DOI: 10.3390/toxins7083210] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 07/31/2015] [Accepted: 08/11/2015] [Indexed: 11/16/2022] Open
Abstract
Zearalenone and its metabolites, α-zearalenol and β-zearalenol, demonstrate estradiol-like activity and disrupt physiological functions in animals. This article evaluates the carryover of zearalenone and its selected metabolites from the digesta to intestinal walls (along the entire intestines) in pre-pubertal gilts exposed to low doses of zearalenone over long periods of time. The term “carryover” describes the transfer of mycotoxins from feed to edible tissues, and it was used to assess the risk of mycotoxin exposure for consumers. The experimental gilts with body weight of up to 25 kg were per os administered zearalenone at a daily dose of 40 μg/kg BW (Group E, n = 18) or placebo (Group C, n = 21) over a period of 42 days. In the first weeks of exposure, the highest values of the carryover factor were noted in the duodenum and the jejunum. In animals receiving pure zearalenone, the presence of metabolites was not determined in intestinal tissues. In the last three weeks of the experiment, very high values of the carryover factor were observed in the duodenum and the descending colon. The results of the study indicate that in animals exposed to subclinical doses of zearalenone, the carryover factor could be determined by the distribution and expression of estrogen receptor beta.
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Affiliation(s)
- Łukasz Zielonka
- Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Olsztyn 10-719, Poland.
| | - Agnieszka Waśkiewicz
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań 60-625, Poland.
| | - Monika Beszterda
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań 60-625, Poland.
| | - Marian Kostecki
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań 60-625, Poland.
| | - Michał Dąbrowski
- Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Olsztyn 10-719, Poland.
| | - Kazimierz Obremski
- Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Olsztyn 10-719, Poland.
| | - Piotr Goliński
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań 60-625, Poland.
| | - Maciej Gajęcki
- Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Olsztyn 10-719, Poland.
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Waśkiewicz A, Beszterda M, Kostecki M, Zielonka Ł, Goliński P, Gajęcki M. Deoxynivalenol in the gastrointestinal tract of immature gilts under per os toxin application. Toxins (Basel) 2014; 6:973-87. [PMID: 24603665 PMCID: PMC3968371 DOI: 10.3390/toxins6030973] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 02/13/2014] [Accepted: 02/17/2014] [Indexed: 12/29/2022] Open
Abstract
Deoxynivalenol is also known as vomitoxin due to its impact on livestock through interference with animal growth and acceptance of feed. At the molecular level, deoxynivalenol disrupts normal cell function by inhibiting protein synthesis via binding to the ribosome and by activating critical cellular kinases involved in signal transduction related to proliferation, differentiation and apoptosis. Because of concerns related to deoxynivalenol, the United States FDA has instituted advisory levels of 5 µg/g for grain products for most animal feeds and 10 µg/g for grain products for cattle feed. The aim of the study was to determine the effect of low doses of deoxynivalenol applied per os on the presence of this mycotoxin in selected tissues of the alimentary canal of gilts. The study was performed on 39 animals divided into two groups (control, C; n = 21 and experimental, E; n = 18), of 20 kg body weight at the beginning of the experiment. Gilts received the toxin in doses of 12 µg/kg b.w./day (experimental group) or placebo (control group) over a period of 42 days. Three animals from two experimental groups were sacrificed on days 1, 7, 14, 21, 28, 35 and 42, excluding day 1 when only three control group animals were scarified. Tissues samples were prepared for high performance liquid chromatography (HPLC) analyses with the application of solid phase extraction (SPE). The results show that deoxynivalenol doses used in our study, even when applied for a short period, resulted in its presence in gastrointestinal tissues. The highest concentrations of deoxynivalenol reported in small intestine samples ranged from 7.2 (in the duodenum) to 18.6 ng/g (in the ileum) and in large intestine samples from 1.8 (in transverse the colon) to 23.0 ng/g (in the caecum). In liver tissues, the deoxynivalenol contents ranged from 6.7 to 8.8 ng/g.
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Affiliation(s)
- Agnieszka Waśkiewicz
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań 60-625, Poland.
| | - Monika Beszterda
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań 60-625, Poland.
| | - Marian Kostecki
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań 60-625, Poland.
| | - Łukasz Zielonka
- Department of Veterinary Prevention and Feed Hygiene, University of Warmia and Mazury in Olsztyn, Olsztyn 10-719, Poland.
| | - Piotr Goliński
- Department of Chemistry, Poznań University of Life Sciences, Wojska Polskiego 75, Poznań 60-625, Poland.
| | - Maciej Gajęcki
- Department of Veterinary Prevention and Feed Hygiene, University of Warmia and Mazury in Olsztyn, Olsztyn 10-719, Poland.
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Gajęcka M, Stopa E, Tarasiuk M, Zielonka Ł, Gajęcki M. The expression of type-1 and type-2 nitric oxide synthase in selected tissues of the gastrointestinal tract during mixed mycotoxicosis. Toxins (Basel) 2013; 5:2281-92. [PMID: 24284830 PMCID: PMC3847727 DOI: 10.3390/toxins5112281] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 11/12/2013] [Accepted: 11/18/2013] [Indexed: 01/19/2023] Open
Abstract
The aim of the study was to verify the hypothesis that intoxication with low doses of mycotoxins leads to changes in the mRNA expression levels of nitric oxide synthase-1 and nitric oxide synthase-2 genes in tissues of the gastrointestinal tract and the liver. The experiment involved four groups of immature gilts (with body weight of up to 25 kg) which were orally administered zearalenone in a daily dose of 40 μg/kg BW (group Z, n = 18), deoxynivalenol at 12 μg/kg BW (group D, n = 18), zearalenone and deoxynivalenol (group M, n = 18) or placebo (group C, n = 21) over a period of 42 days. The lowest mRNA expression levels of nitric oxide synthase-1 and nitric oxide synthase-2 genes were noted in the sixth week of the study, in particular in group M. Our results suggest that the presence of low mycotoxin doses in feed slows down the mRNA expression of both nitric oxide synthase isomers, which probably lowers the concentrations of nitric oxide, a common precursor of inflammation.
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Affiliation(s)
- Magdalena Gajęcka
- Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, ul. Oczapowskiego 13/29, Olsztyn 10-718, Poland; E-Mails: (L.Z.); (M.G.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +48-89-523-32-37; Fax.: +48-89-523-36-18
| | - Ewa Stopa
- Veterinary Clinic, Ewa Stopa DVM, ul. Dąbrowskiego 15, Iława 14-200, Poland; E-Mail:
| | - Michał Tarasiuk
- BIOMIN Polska Sp. z o.o., ul. Grochowska 16, Warszawa 04-217, Poland; E-Mail:
| | - Łukasz Zielonka
- Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, ul. Oczapowskiego 13/29, Olsztyn 10-718, Poland; E-Mails: (L.Z.); (M.G.)
| | - Maciej Gajęcki
- Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, ul. Oczapowskiego 13/29, Olsztyn 10-718, Poland; E-Mails: (L.Z.); (M.G.)
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Long-term dietary L-arginine supplementation increases endothelial nitric oxide synthase and vasoactive intestinal peptide immunoexpression in rat small intestine. Eur J Nutr 2013; 53:813-21. [PMID: 24100601 DOI: 10.1007/s00394-013-0585-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 09/05/2013] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS Nitric oxide (NO) and vasoactive intestinal polypeptide (VIP) are important intestinal neurotransmitters that coexist in the gut enteric nervous system and play an important role in intestinal physiology (e.g., absorption, motility, fluid secretion and smooth muscle relaxation). It is also known that cold exposure alters several aspects of gastrointestinal physiology and induces hyperphagia to meet increased metabolic demands, but there are no data regarding NO and VIP involvement in intestinal response during acclimation to cold. The objective of this study was to determine the influence of long-term L-arginine supplementation on the expression of the three isoforms of nitric oxide synthase (NOS) and VIP in small intestine of rats acclimated to room temperature or cold. METHODS Animals (six per group) acclimated to room temperature (22 ± 1 °C) and cold (4 ± 1 °C), respectively, were treated with 2.25% L-arginine, a substrate for NOSs, or with 0.01% N(ω)-nitro-L-arginine methyl ester, an inhibitor of NOSs, for 45 days. The topographical distribution of VIP and NOSs expression in small intestine was studied by immunohistochemistry, and ImageJ software was used for semiquantitative densitometric analysis of their immunoexpression. RESULTS Long-term dietary L-arginine supplementation increases VIP and NOSs immunoexpression at room temperature while at cold increases the endothelial NOS, inducible NOS and VIP but decrease neuronal NOS in rat small intestine. CONCLUSION Our results demonstrate that long-term dietary L-arginine supplementation modulates NOSs and VIP immunoexpression in rat small intestine with respect to ambient temperature, pointing out the eNOS as a predominant NOS isoform with an immunoexpression pattern similar to VIP.
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