Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Duodenum”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources

Penetration of the duodenum by an ingested needle with migration to the pancreas: report of a case.

A case of a penetration of the duodenum by a needle with migration to the pancreas in a 50-year-old man is reported herein. The patient was referred to us with a chief complaint of diarrhea. An abdominal plain roentgenogram showed a needle in the upper abdominal area. An abdominal computed tomography scan and contrast X-ray revealed the foreign body to be located outside of the duodenum and in the head of the pancreas. An emergency operation was therefore performed on the first day and the needle in the head of the pancreas was thus extirpated safely. A perforation of the gastrointestinal tract by an ingested foreign body is difficult to accurately and quickly diagnose when no peritonitis or abscess formation is observed. Therefore, the use of contrast X-ray is considered to be useful in the diagnosis of such a perforation.

Contrast Media↗

Superior mesenteric artery syndrome involving the duodenum and jejunum.

Superior mesenteric artery (SMA) syndrome is a rare cause of intestinal obstruction involving the duodenum. Diagnosis is based on clinical suspicion with radiologic confirmation. We report an unusual presentation of the SMA syndrome involving both the duodenum and jejunum initially not recognized on contrast-enhanced CT. This case demonstrates the judicious use of multiple modalities in evaluating for this syndrome.

Aged↗

Duodenum-preserving pancreatic head resection: Long-term results.

Early and late results from 298 patients with chronic pancreatitis who were surgically treated by means of duodenum-preserving pancreatic head resection (DPPHR) were prospectively analyzed. The aim of this operative procedure is to treat complications of chronic pancreatitis caused by inflammatory enlargement of the pancreatic head by decompressing the common bile duct, the pancreatic duct, the duodenum, and the retropancreatic intestinal vessels. End points of the study were early and late postoperative outcome. The follow-up period ranged from 1 to 22 years with a median follow-up of 6 years. In-hospital mortality was 1%, postoperative morbidity was 28.5%, and the rate of repeat laparotomy was 5.7%. Diabetes mellitus developed early in the postoperative period in six patients (2%). After a median follow-up of 6 years, late mortality was 8.9%. In the late follow-up period 88% of our patients were completely free of pain or had infrequent episodes and 63% were able to return to work. DPPHR might be considered as an alternative surgical technique in the treatment of chronic pancreatitis if the dominant lesion is in the pancreatic head.

Adult↗

Duplication of the duodenum extending into liver.

A large intrahepatic duodenal duplication connected to the duodenum by two openings is described. No similar cases of intrahepatic cysts have been found in the literature. The patient, a forty-four year old woman, had recurrent and numerous bouts of right upper quadrant pain over many years before the intrahepatic portion of the cyst was drained by a Roux-en-Y anastomosis after the connections with the duodenum had been excised.

Adult↗

Effects of potassium ions and sodium ions on membrane potential of epithelial cells in rat duodenum.

1. Mucosal and serosal membrane potentials (Vm and Vs) of epithelial cells in rat duodenum were recorded together with the transmural potential differences (PDt). 2. The value of Vm in rat duodenum at 37 degrees C was about -53mV, being considerably greater than the values reported hitherto for the small intestine of various species. 3. When Cl- in the mucosal medium was partially replaced with SO42- at fixed mucosal Na+ and K+ concentrations ([Na+]m and [K+]m), the membrane potential was scarcely affected in the steady state several minutes after replacement, whereas marked changes in the potential were observed with varying [K+]m or [Na+]m. 4. As the mucosal K+ concentration increased at constant [Na+]m, Vm was gradually decreased (depolarization), together with the increase in PDt. Such a change in Vm caused by varying [K+]m obeys Nernst's equation in the range of [K+]m higher than about 60 mM. 5. At constant [K+]m, an increase in [Na+]m also caused the decrease of Vm for the lower [K+]m region, whereas Vm was not affected by such changes in [Na+]m in the range of [K+]m higher than approx. 60 mM. 6. The values of PNa/PK were obtained from the modified Goldman equation under an appropriate assumption. The ratio of the permeability coefficients markedly increases from zero to approx. 0.07 with a decrease in [K+]m.

Animals↗

Permeability properties and intracellular ion concentrations of epithelial cells in rat duodenum.

Effects of the K+ concentration in the bathing fluid ([K+]l) on the intracellular K+, Na+ and Cl- concentrations ([K+]i [Na+]i and [Cl-]i) as well as on the electrical potential were studied in rat duodenum. Changes in the mucosal K+ concentration ([K+]m), bringing the sum of Na+ and K+ concentrations to 147.2 mM constant, had little effect on the transmural potential difference (PDt), but did induce marked changes in the mucosal membrane potential (Vm). As [K+]m increased, Vm was depolarized gradually and obeyed the Nernst equation for a potassium electrode in the range of [K+]m greater than approx. 60 mM. Experiments of ion analyses were carried out on strips of duodenum to determine the effect of changing the external K+ concentrations on [K+] i, [Na+]i and [Cl-]i. An increase in [K+]o resulted in increases in [K+]i and [Cl-]i and a decrease in [Na+]i, [K+]i approaching its maximum at [K+]o greater than 70 mM. Such changes in [K+]i and [Na+]i seem to correlate quantitatively with the changes in [K+]o and [Na+]o. The values of the ratio of permeability coefficients, Pna+/PK+ were estimated using the Vm values and intracellular ion concentrations measured in these experiments. The results suggested that there appeared a rather abrupt increase in the PNa+/PK+ ratio from 0 to approx. 0.1, as [K+]m decreased.

Animals↗

Phosphate transport by embryonic chick duodenum. Stimulation by vitamin D3.

Embryonic chick duodenum maintained in organ culture is a well-suited model for the study of vitamin D effects on inorganic phosphate (Pi) absorption. The system is sensitive to as little as 6.5 nM vitamin D3 (0.1.I.U./ml culture medium). Increased phosphate absorption is observed after 6--12 h of culture. Maximal response (133% of vitamin D-efficient control) is achieved at 24 h. Phosphate uptake by embryonic chick duodenum involves a saturable and a non-saturable component. The former displays characteristics of an active sodium-dependent transport mechanism and is also sensitive to vitamin D3. Presence of the sterol in culture medium raises the maximal velocity from 55 to 75 nmol Pi/min per g tissue. Km remains unchanged (0.5 mM Pi). Duodena cultured in presence of inhibitors of protein synthesis (actinomycin D, alpha-amanitin and cycloheximide) display reduced rates of phosphate absorption. This treatment also prevents vitamin D3 action on phosphate transport. It is concluded that the sterol affects phosphate transport by modulation of synthesis of proteins which are functional in the Pi absorptive process.

Animals↗

Distribution of Ca2+-ATPase, ATP-dependent Ca2+-transport, calmodulin and vitamin D-dependent Ca2+-binding protein along the villus-crypt axis in rat duodenum.

The migration of intestinal epithelial cells from the crypts to the tips of villi is associated with progressive cell differentiation. The changes in Ca2+-ATPase activity and ATP-dependent Ca2+-transport rates in basolateral membranes from rat duodenum were measured during migration along the crypt-villus axis. In addition, vitamin D-dependent calcium-binding protein and calmodulin content were measured in homogenates of six cell populations which were sequentially derived from villus tip to crypt base. Alkaline phosphatase activity was highest at the tip of the villus (fraction I) and decreased more than 20-fold towards the crypt base (fraction VI). (Na+ + K+)-ATPase activity also decreased along the villus-crypt axis but in a less pronounced manner than alkaline phosphatase. ATP-dependent Ca2+-transport in basolateral membranes was highest in fraction II (8.2 +/- 0.3 nmol Ca2+/min per mg protein) and decreased slightly towards the villus tip and base (fraction V). The youngest cells in the crypt had the lowest Ca2+-transport activity (0.9 +/- 0.1 nmol Ca2+/min per mg protein). The distribution of high-affinity Ca2+-ATPase activity in basolateral membranes correlated with the distribution of ATP-dependent Ca2+-transport. The activity of Na+/Ca2+ exchange was equal in villus and crypt basolateral membranes. Compared to the ATP-dependent Ca2+-transport system, the Na+/Ca2+ exchanger is of minor importance in villus cells but may play a more significant role in crypt cells. Calcium-binding protein decreased from mid-villus towards the villus base and was undetectable in crypt cells. Calmodulin levels were equal along the villus-crypt axis. It is concluded that vitamin D-dependent calcium absorption takes primarily place in villus cells of rat duodenum.

Alkaline Phosphatase↗

Adrenocorticotropin and beta-endorphin are colocalized in the nervous system of rat duodenum.

Adrenocorticotropin and beta-endorphin-like immunoreactivities were visualized by an immunohistochemical method on adjacent serial sections of the nervous system of the rat duodenum. Perikarya lying in the myenteric plexus and stained alternately for ACTH or beta-endorphin, showed on two adjacent serial sections a co-existence of these two peptides within one and the same perikarya. A co-localization of beta-endorphin and ACTH is not demonstrated with certainty in the submucous plexus. These results may be evidence for a common occurrence of the two peptides within perikarya of the rat duodenum.

Adrenocorticotropic Hormone↗

Colocalization of dynorphin-A(1-17) and dynorphin-A(1-8) within some perikarya of rat duodenum: immunohistochemical evidence for the presence of two separate dynorphinergic systems.

Adjacent serial sections through the rat duodenum were alternately stained for immunofluorescence microscopic studies with specific anti-sera directed to the opioid peptides dynorphin-A(1-17) and dynorphin-A(1-8), respectively. This resulted in the evidence that two separate dynorphinergic neuron populations are present there: intramural neurons, revealing a colocalization of dynorphin-A(1-17) and dynorphin-A(1-8), were round, contained a large and round nucleus and were lying sporadically in the longitudinal muscle layer as well as bulb-shaped neurons expressing only a dynorphin-A(1-8) immunoreactivity. The latter were recognized abundantly in the myenteric plexus. Myenteric plexus nerve fibres and terminals were immunoreactive for dynorphin-A(1-8), but not for dynorphin-A(1-17). Dynorphin-A(1-8) immunostained nerve terminals formed close contacts with large non-dynorphinergic myenteric plexus perikarya. These findings might indicate that dynorphin-A(1-8) is processed directly from its prodynorphin ('preproenkephalin B') precursor within myenteric plexus perikarya and indirectly via dynorphin-A(1-17) within intramural perikarya, indicating the presence of two separate dynorphinergic systems in the rat duodenum.

Animals↗

Dynorphin-A(1-8) and gamma-melanotropin exist within different myenteric plexus neurons of rat duodenum.

Using the adjacent serial section staining technique and the double staining elution method, it was demonstrated that the opioid peptide dynorphin-A(1-8), originating from the prodynorphin precursor, and gamma 3-melanotropin (gamma 3-MSH), originating from the pro-opiomelanocortin (POMC) precursor, did not co-exist within myenteric plexus perikarya of the rat duodenum. This finding resembles that of the rat brain. Whether gamma 3 -MSH and dynorphin-A(1-8) act synergistically or antagonize each other in some physiological functions or have no interaction at all in the rat duodenum is as yet unknown.

Animals↗

Topography of cholinergic perikarya and nerve fibres as well as cholinergic vesicles in the rat duodenum.

Using the acetylthiocholine staining method, it was possible to visualize acetylcholinesterase (AChE)-stained neuronal cell bodies and nerve endings as well as AChE-positive vesicles in the rat duodenum. AChE-reactive perikarya were seen with certainty only in the myenteric plexus. They were 40 micron in diameter and were mostly localized in groups within the ganglia (3-6 neurons per ganglion). Some thick, AChE-reactive nerve processes, running over a long distance in interconnecting nerve fibre strands, had their origin from AChE-containing myenteric plexus perikarya. AChE-stained nerve fibres were detected in the myenteric and submucosal plexus as well as in the longitudinal and circular smooth muscle cell layer. AChE-positive nerve fibres were in close contacts with blood vessels, probably arterioles, Brunner's gland cells and epithelial cells. A conspicuously high density of AChE-positive nerve fibres was noted in the longitudinal smooth muscle layer, while AChE-stained nerve fibres were visualized only sporadically in the circular smooth muscle layer. Some Brunner's gland cells and epithelial cells contained AChE-reactive vesicles, which were constantly localized on the basal cell portion. The present findings might indicate that acetylcholine possesses important physiological roles as neurotransmitter and/or neuromodulator in the rat duodenum.

Acetylcholinesterase↗

A difference in effects of physiological Ca2+ concentrations on activity of guanylate cyclase preparations obtained from the taenia caecum of guinea pig and from the longitudinal muscle of rat duodenum.

A cholinergic stimulant, butyltrimethylammonium bromide and serotonin increased the tissue levels of cyclic GMP in the taenia caecum of guinea pig but not those in the longitudinal muscle of rat duodenum. On the other hand, physiological Ca2+ concentrations enhanced the activity of a guanylate cyclase preparation obtained from the taenia caecum of guinea pig, while guanylate cyclase in the longitudinal muscle of rat duodenum was not influenced by Ca2+. The difference in the effects of the smooth muscle stimulants on the tissue levels of cyclic GMP in two different smooth muscles in attributed to differences in the properties of guanylate cyclase of smooth muscles.

Animals↗

Further evidence for involvement of adenosine-5'-triphosphate in non-adrenergic non-cholinergic relaxation of the isolated rat duodenum.

The nature of the inhbitory non-adrenergic non-cholinergic (NANC) neurotransmitter responsible for neurogenic relaxation of rat duodenum was studied with in vitro techniques. Adenosine 5'-triphosphate (ATP)(1 mM), gamma-aminobutyric acid (GABA, 1 mM), dimethylphenylpiperazinium (DMPP, 0.1 mM) and field stimulation (60 V, 2 ms, 0.1 Hz) produced transient relaxation followed by rebound contraction. In contrast vasoactive intestinal polypeptide (VIP) (0.3 microM) and noradrenaline (1 microM) induced relaxation which set in more slowly and lasted longer. Tetrodotoxin (0.85 microM) abolished field stimulation-induced relaxation but not ATP-, VIP- or noradrenaline-induced relaxation. Nucleotide pyrophosphatase (0.25 U/ml), but not the proteolytic enzyme alpha-chymotrypsin (2 U/ml), selectively antagonized NANC relaxation. The rank order of potency of various adenine derivatives for inducing relaxation was adenosine-5'-triphosphate greater than adenosine-5'-diphosphate much greater than adenosine greater than adenosine-5'-monophosphate. ATP-induced relaxation was selectively antagonized by the putative P2 purinoceptor antagonist reactive blue 2, but unaffected by the selective P1 purinoceptor antagonist 8-phenyltheophylline. The duration of ATP- as well as beta-gamma-methylene adenosine-5'-triphosphate (a stable analogue of ATP)-induced relaxation was similar and was unaffected by indomethacin 10 microM (which abolished the rebound contraction). In those preparations whose contractile tone was increased by using a high-K+ medium the ability of ATP to elicit relaxation was markedly reduced, while GABA- and DMPP-induced relaxation was abolished. On the other hand, ATP-, GABA- and DMPP-induced relaxation of the tonic component of 5-hydroxytryptamine (5-HT)(0.1 mM)-induced contraction was similar to that observed in control conditions. These findings add further weight to the proposal that endogenous ATP is involved in determining NANC relaxation of rat duodenum.

Adenosine↗

Effects of pGlu-His-Pro-amphetamine (TRH-amphetamine) on the isolated duodenum of the guinea-pig: antagonistic effect of amphetamine on TRH response.

pGlu-His-Pro-dexamphetamine (TRH-A) produced a contraction through the release of acetylcholine from postganglionic cholinergic neurons in the duodenum of the guinea-pig in the same manner as TRH. However, the affinity of TRH-A (pD2, 4.70) toward isolated duodenum was one thousandth that of TRH (pD2, 7.74). The effects of TRH-A (10(-4)M) were abolished by 10(-7) M TRH, but only partially (about 50%) inhibited by 10(-4) M d-amphetamine. D-Amphetamine showed no stimulatory effect on the myenteric nerves. However, the duodenal response to TRH (10(-6) M) was dose dependently inhibited by d-amphetamine (10(-6), 10(-5), 10(-4) M) while the phasic and tonic contractions caused by high K+ (40 mM) or the contractile responses to acetylcholine (10(-7) M) were not blocked by d-amphetamine. These results indicate that d-amphetamine may act as an antagonist to TRH without influencing the movement of calcium ions in smooth muscle or muscarinic receptors and that contractile responses to TRH-A are mediated through TRH receptors in the myenteric cholinergic nerves.

Acetylcholine↗

Evidence against purines being neurotransmitters of non-adrenergic, non-cholinergic nerves in rat duodenum.

The possible involvement of purines in the non-adrenergic non-cholinergic (NANC) relaxation of rat duodenum was studied using an isometric-isovolumic preparation. Purines (adenosine, AMP, ADP, ATP) induced a concentration-dependent, tetrodotoxin (TTX)-insensitive, fall in both endoluminal pressure and isometric tension. The relaxation induced by adenosine and by 2-chloroadenosine was selectively antagonized by 8-phenyltheophylline (1, 10 nM, 0.5 microM) and the ATP-induced relaxation was opposed by alpha, beta-methylene ATP (10 microM) and by reactive blue 2 (10 microM). Electrical field stimulation (EFS) caused TTX-sensitive inhibitory effects similar to those induced by ATP. None of the purinergic antagonists used were capable of affecting the EFS-induced relaxation. Our results indicate that both P1 and P2 purinoreceptors are present in muscle of the rat duodenum and are not involved in the NANC relaxation.

Adenosine↗

Bradykinin B2 receptor evoked K+ permeability increase mediates relaxation in the rat duodenum.

We have investigated the receptors and associated coupling mechanisms that mediate the smooth muscle relaxant response to bradykinin (BK) in the rat duodenum in vitro. Relaxation in response to BK seems due to a direct action on the longitudinal smooth muscle since effects were demonstrable in the presence of ibuprofen, mepyramine, atropine, guanethidine (all 1 microM), hexamethonium (10 microM) and TTX (0.3 microM). Receptors involved are of the B2 subtype since agonists and antagonists active at B1 receptors were essentially inactive, and the B2 receptor antagonist Lys,Lys-[Hyp3,Thi5,8,D-Phe7]BK was a potent competitive antagonist of BK-induced relaxation (pKB of 7.2 +/- 0.1). The activity of both BK and the antagonist were unchanged by the presence of peptidase inhibitors including the carboxypeptidase inhibitor DL-2-mercaptomethyl-3-guanidinoethylthiopropanoic acid (mergetpa, 10 microM), which prevents conversion of BK analogues to des-Arg9-B1-active products. In high-K+ solution, BK (0.1-10 microM) produced concentration-related increases in 86Rb efflux. Both this permeability increase in high-K+ solution, and the relaxant responses in Krebs solution, were inhibited by low concentrations (10-100 nM) of apamin, as well as the B2 receptor antagonist Lys,Lys-[Hyp3,Thi5,8,D-Phe7]BK (1 microM). These results are compatable with the proposal that BK-evoked relaxation of the rat duodenum is mediated via a subset of B2 receptors for which the antagonist Lys,Lys-[Hyp3,Thi5,8,D-Phe7]BK has a high affinity, and results from stabilisation of the smooth muscle membrane through the opening of apamin-sensitive 86Rb-permeable calcium-activated K+ channels.

Animals↗

L-NG-nitro-arginine inhibits nicotine-induced relaxation of isolated rat duodenum.

We studied the effects of L-NG-nitro-arginine (L-NOARG), which inhibits nitric oxide (NO) biosynthesis from L-arginine, on the non-adrenergic, non-cholinergic (NANC)-mediated relaxation induced by nicotine in isolated rat duodenum. L-NOARG reduced nicotine-induced relaxation, and L-arginine prevented the inhibitory effect of L-NOARG. However, L-NOARG did not inhibit the tetrodotoxin-insensitive relaxation induced by adenosine 5'-triphosphate, alpha, beta-methyleneadenosine 5'-triphosphate, thyrotropin-releasing hormone or the calcitonin gene-related peptide. Endogenous NO thus could possibly be involved in the NANC-mediated relaxation of rat duodenum induced by nicotine.

Adenine Nucleotides↗