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1

Effect of subdiaphragmatic vagotomy and cholinergic agents in the hypothalamic-pituitary-adrenal axis activity

100%

Bugajski A. J., Zurowski D., Thor P., Gadek-Michalska A.

Journal of Physiology and Pharmacology

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2007

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tom 58

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nr 2

In the present study, we examined whether the vagus nerve is involved in mediating the stimulation of hypothalamic-pituitary-adrenal (HPA) axis by cholinergic muscarinic and nicotinic agonists, carbachol and nicotine. The site of HPA axis muscarinic stimulation was determined using peripheral (i.p.) and intracerebroventricular (i.c.v.) administration of carbachol, atropine sulphate (AtrS) and atropine hydrobromide (AtrBr). The i.p. carbachol-(0.5 mg/kg)-induced corticosterone response was significantly reduced by i.p. pretreatment with AtrBr (0.1 mg/kg), but was not diminished by i.c.v. AtrS (0.1µg). The increase in corticosterone secretion induced by i.c.v. carbachol (2 µg) was totally abolished by i.c.v. pretreatment with AtrS (0.1 µg) but was not altered by i.p. AtrBr. Subdiaphragmatic vagotomy performed 2 weeks earlier substantially decreased the i.p. carbachol (0.2 mg/kg)-induced ACTH response and markedly augmented ACTH and corticosterone response to a higher dose of carbachol (0.5 mg/kg) in comparison with the responses in sham operated rats. Vagotomy abolished the stimulatory effect of i.p. nicotine in a low dose (1 mg/kg) on ACTH and corticosterone secretion; the ACTH response to higher dose (2.5 mg/kg) was considerably reduced, while corticosterone response remained unaffected. These results suggest that carbachol given i.c.v. evokes considerable corticosterone response by stimulation of central cholinergic muscarinic receptors. A major part of the i.p. carbachol-induced corticosterone secretion results from peripheral cholinergic muscarinic receptor stimulation. Subdiaphragmatic vagotomy moderately intensified the carbachol-induced ACTH and corticosterone secretion. Vagotomy significantly reduced the nicotine-induced ACTH secretion, possibly by the involvement of vagal afferents. The nicotine-induced corticosterone secretion is not exclusively regulated by circulating ACTH but by various intra-adrenal regulatory components.

2

Morphological examination of the proximal ganglion of the vagus nerve in the pig

86%

Sienkiewicz W., Dudek A.

Polish Journal of Veterinary Sciences

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2009

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tom 12

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nr 4

This is the first report dealing with the localisation and morphology of the proximal (jugular) ganglion in the pig. Six 3 months old pigs of both sexes were used in this study. Tissues were stained with three histological methods: Klu¨ver-Barer counterstained with Cresyl violet, Haematoxylin-eosin and Mayer’s haematoxylin. The localisation and morphological features of the ganglion and ganglionic neurones were described and discussed.

3

Branches of the recurrent laryngeal nerves in the vicinity of the inferior thyroid arteries

86%

Stryjewska-Makuch G., Aleksandrowicz R.

Folia Morphologica

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1990

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tom 49

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nr 1-2

4

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Increase of cardiodepressant activity in medium incubating the posterior pituitary lobe in situ during vagal nerve stimulation in rat

86%

Goraca A., Traczyk W. Z.

Journal of Physiology and Pharmacology

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1991

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tom 42

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nr 3

Previous studies have indicated that there is a cardiodepressant factor in the medium incubating the posterior pituitary lobe in situ. The cardiodepressant activity of the medium incubating the posterior pituitary lobe before and during stimulation of the vagus nerves was tested on isolated auricles of the right heart atrium of a two-day-old rat. It was found that the medium incubating the posterior pituitary lobe collected before stimulation decreased the contraction rate of the auricle by 34%, while that collected during the intermittent stimulation of the central ends of the cut vagus nerves caused a decrease of the auricle contractions frequency by 52%. The addition of cholinergic, serotoninergic, histaminergic receptor blockers or prostaglandin synthetase into Ringer-Lock’s solution bathing the auricle has no effect on the changes of the contraction rate caused by the incubation medium.

5

The ghrelin pentapeptide inhibits the secretion of pancreatic juice in rats

86%

Kapica M., Laubitz D., Puzio I., Jankowska A., Zabielski R.

Journal of Physiology and Pharmacology

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2006

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tom 57

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nr 4

Ghrelin, a 28 amino acids polypeptide was recognized as an endogenous ligand for the growth hormone secretagogue receptor. It turned out that the entire sequence of ghrelin is not necessary for performing the above-mentioned functions. It was suggested that 5 residues (Gly-Ser-Ser(n-octanoyl)-Phe, pentaghrelin) constituted functionally active part of the full-length polypeptide. Ghrelin-28 was found to inhibit pancreatic enzyme output in rats, though the effect of pentaghrelin was not studied so far. The study aimed to determine the involvement of pentaghrelin in pancreatic juice secretion in anaesthetized rats. Male Wistar rats (220 ± 20 g body weight, b. wt.) were anesthetized, the external jugular vein and common biliary-pancreatic duct were cannulated. Pentaghrelin boluses (iv, 1.2, 12, and 50 nmol kg-1 b. wt.) were injected every 30 min with or without CCK-8 infusion, duodenal mucosal CCK1 receptor blockade with tarazepide, vagotomy and capsaicin pretreatment. Pentaghrelin boluses reduced the volume of pancreatic-biliary juice, protein and trypsin outputs both under basal and CCK-8-stimulated conditions in a dose-dependent manner. However, exogenous pentaghrelin failed to affect the pancreatic secretion in rats subjected to vagotomy, capsaicin deactivation of afferents or pretreatment with Tarazepide. In conclusion, pentaghrelin may control exocrine pancreas secretion by affecting duodenal neurohormonal mechanism(s) involving CCK and vagal nerves in rats.

6

Involvement of vagal opioid receptors in respiratory effects of morphine in an anaesthetized rats

86%

Kaczynska K., Szereda-Przestaszewska M.

Journal of Physiology and Pharmacology

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2005

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tom 56

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nr 2

Respiratory effects of morphine injection to the femoral vein were investigated in urethane and chloralose anaesthetized and spontaneously breathing rats, prior to and after midcervical vagotomy. Bolus injection of morphine HCl at a dose of 2 mg/kg of body weight induced depression of ventilation in all rats, due to the significant decrease in tidal volume and to the decline in respiratory rate both pre- and post-vagotomy. Expiratory apnoea of mean duration of 10.0±3.4 s was present in the vagally intact rats only. Bilateral midcervical section of the vagus nerve precluded the occurrence of apnoea. Prolongation of the expiratory time (TE morphine / TE control), which amounted to10.7±2.2-fold in the intact state, was apparently reduced to 1.5±0.3-fold after division of the vagi. Morphine significantly decreased mean arterial pressure (MAP) at 30 s after the challenge, the effect persisted for not less than 1 minute and was absent in vagotomized rats. The respiratory changes evoked by morphine reverted to the control level after intravenous injection of naloxone at a dose of 1 mg/kg. Results of this study indicate that opioid receptors on vagal afferents are responsible for the occurrence of apnoea and hypotension evoked by morphine.

7

Capsaicin induced deafferentiation enhances the effect of electrical vagal nerve stimulation on food intake and body mass

86%

Laskiewicz J., Krolczyk G., Zurowski D., Enck P., Thor P. J.

Journal of Physiology and Pharmacology

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2004

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tom 55

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nr 1,2

Study was based on hypothesis that electrical stimulation (ES) with parameters obtained from analysis of vagal afferent discharge fed state may fake brain with satiety state. We evaluated effect of denervation of vagal capsaicin-sensitive afferents on food intake and body weight in rats with ES of vagal nerves using microchip (MC). Group A was scheduled to MC implantation, B to sham operation only, C to MC implantation and capsaicin vagal deafferentation, and D to capsaicin denervation only. ES lasted 24 days. MC parameters were 0.05Hz, 0.1s, 0.55V. ES of left vagus significantly reduced total food intake as well as the mean daily intake in groups A and C in comparison to control and D group (ANOVA, F=18.55, p=0.0038). Body weight was lower in group A (346,2 g) and C (272,7 g) then in control (381,4 g) and D (356,8 g) (F=25.68, p=0.00068). Leptin decreased in C (165 pg/mL) in comparison to A (625 pg/mL), B (677 pg/mL), and D (612 pg/mL) (p<0,05), mainly due to ES (F=7.27, p=0.019). Glucose was decreased in A (F=5.55, p=0.036) - by 11 % and by 16% in C group. Proper vagal neuromodulation results in central and peripheral effects causing food intake and body weight downregulation.

8

Measurements of the Obersteiner-Redlich zone of the vagus nerve and their possible clinical applications

86%

Sloniewski P., Korejwo G., Zielinski P., Morys J., Krzyzanowski M.

Folia Morphologica

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1999

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tom 58

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nr 1

The aim of our study was to describe anatomical variability of the root entry zone (REZ), also called the Ohersteiner--Redlich zone, that represents the "junction zone" of glia and Schwann sheath of the cranial nerves. This zone has some clinical implications. The pulsatile compression of REZ by a vessel may produce clinical symptoms, such us trigeminal neuralgia, hemifacial spasm, glossopharyngeal neuralgia torticollis spasmodicus or even symptoms of essential hypertension when a vascular crross compression of REZ of a left vagus nerve is present. The vessel - cranial nerve contact in the skull base cysterns may be visualized in radiologic examinations, most accurately in magnetic resonance imaging. Because, we cannot distinguish the REZ from the rest of the vagus nerve in radiologic examinations we decided to measure the lenght of its REZ. The microanatomical study of the lenght of REZ zone of the vagus nerve was performed on 2l nerves taken from 17 human brain stems (12 men, 5 women, 14 left, 7 right), fixed with 8% buffered, formalin solution. Paraffin embedded tissue was cut into 1O-um-thick sections pararellel to the nerve longitudinal axis and stained with hematoxilin & eosin. Each of the nerves showed the presence of a zone of oligodendrocyte myelination, mean lenght 2 ą 0.3 mm. In 17 nerves the transitional zone formred a cone-like process, in 4 nerves was shaped irregularly. The length of REZ (oligodendrocyte myelination plus "glial dome") had the mean length 3.5 ą 0,9 mm.

9

Influence of vagal nerve stimulation on food intake and body weight - results of experimental studies

72%

Sobocki J., Krolczyk G., Herman R. M., Matyja A., Thor P. J.

Journal of Physiology and Pharmacology. Supplement

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2005

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tom 56

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nr 6

27-33

The paper reviews recent advances in vagal nerve stimulation for the control of food intake and body weight. The vagal nerves are the predominant pathway in the "brain-gut axis" responsible for short term regulation of food intake. Stimulation of afferent vagal traffic attenuates food intake by vagal projections to nucleus tractus solitarius, arcuate nucleus and its convergence’s to thalamic center of satiety. A few studies have been published in this field so far. All of them are consistent and show significant decrease in body mass during vagal stimulation. Due to promising results of experimental studies, clinical trials are expected in the near future.

10

Morphology and development of depressive nerve (nervus depressor) of pig at prenatal stage

72%

Pospieszny N., Kleckowska J., Janeczek M.

Electronic Journal of Polish Agricultural Universities. Series Veterinary Medicine

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2003

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tom 06

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nr 2

11

Luminal CCK and its neuronal action on exocrine pancreatic secretion

72%

Zabielski R.

Journal of Physiology and Pharmacology. Supplement

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2003

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tom 54

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nr 4

81-94

Gut regulatory peptides are produced by mucosal endocrine cells and released both into the circulation as well as into the gut lumen. Following stimulation the distribution between the circulation and gut lumen changes in favor of the gut lumen. In the blood plasma, the biological half-life of gut regulatory peptides is counted in single minutes due to high aminopeptidase activity and liver extraction. In the gut lumen, however, regulatory peptides retain their biological activity much longer, especially in newborn and young animals. A series of studies was performed in neonatal calves and pigs to explore the role of luminal cholecystokinin (CCK) on the regulation of exocrine pancreatic secretion. In anaesthetized neonatal calves, CCK was secreted into the duodenal lumen, and electrical vagal stimulation increased CCK release into the duodenal lumen but not into the circulating blood. In conscious calves, luminal CCK-8 stimulated pancreatic protein secretion by a neurohormonal mechanism dependent on a duodenal mucosal CCK1 receptor and vagal nerve activity. Immunocytochemistry pointed to an association of mucosal CCK1 and CCK2 receptors with neuronal components in the small intestine of neonatal calves. Experiments in calves and pigs with CCK-8 infusions into the duodenal branches of the right gastroepiploic artery confirmed the results of luminal CCK-8 and questioned the physiological relevance of a direct mechanism of CCK on the pancreatic acini.

12

Scanning electron microscope analysis of the distal vagus nerve ganglion (ganglion distale nervi vagi) in newborn calves in standard husbandry

72%

Pospieszny N., Adamski M., Kuropka P.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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2008

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tom 50

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nr 1

13

Short-term depression of inspiratory activity following tonic vagal stimulation

72%

Budzinska K., Ilasz R.

Journal of Physiology and Pharmacology. Supplement

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2006

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tom 57

|

nr 4

55-61

This study tested the role of inhibitory neurotransmission in the glutaminergic control of short-term depression (STD) of the inspiratory activity initiated by sustained stimulation of the vagus nerve in anesthetized and vagotomized cats. STD, calculated from the integrated phrenic nerve signal, lasted longer when glutaminergic neurotransmission was inhibited by ketamine, a NMDA receptor antagonist. Application of picrotoxin, a GABAA receptor antagonist, reversed the effect of ketamine and shortened the STD duration below that present in the control condition. The results showed that alternation of the neural excitability by antagonists of excitatory and inhibitory neurotransmission modulates the STD of inspiratory activity, evoked by vagal stimulation. The STD depends on the state of neural excitability and is easier accomplished when the excitability is on the high side.

14

Komorki zwojowe w nerwach blednych swini domowej

72%

Matysek M., Krakowska I., Boratynski Z., Luszczewska-Sierakowska I.

Acta Scientiarum Polonorum. Medicina Veterinaria

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2003

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tom 02

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nr 1

27-31

15

The structure and topography of the parasympathetic and the ambiguous nuclei of the glossopharyngeal and vagus nerves in the goose [Anser anser]

72%

Arciszewski M. B., Kubacki J.

Annales Universitatis Mariae Curie-Sklodowska. Sectio C, Biologia

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2002

|

tom 57

16

Central and peripheral neural control of pancreatic exocrine secretion

72%

Niebergall-Roth E., Singer M. V.

Journal of Physiology and Pharmacology

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2001

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tom 52

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nr 4,1

Efferent vagal impulses act on the exocrine pancreas via pancreatic ganglia, where the impulses are modulated and modified, and terminate via postganglionic fibers at the acinar cells. Acinar muscarinic receptors of the subtype M1 play an important role for the mediation of the stimulatory vagal influences on pancreatic exocrine secretion. In dogs, a potentiative interaction exists between the two most important mediators of the pancreatic exocrine response to intraduodenal stimuli, efferent vagal impulses and CCK. In contrast to humans and rats, in which all action of CCK on pancreatic enzyme output is vagally mediated, CCK acts in dogs in part as a classical humoral factor independent of the cholinergic system. Although several peptides found in pancreatic nerve cell bodies or fibers can stimulate or inhibit pancreatic exocrine secretion, their physiological importance in the neural control of the exocrine pancreas needs to be further evaluated.

17

Cholecystokinin-like activity in the duodenal lumen of anaesthetized neonatal calves

72%

Zabielski R., Kiela P., Podgurniak P., Gregory P. C., Pierzynowski S. G.

Polish Journal of Veterinary Sciences

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1999

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tom 02

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nr 1

Cholecystokinin like activity was measured in duodenal perfusates obtained from a 30 cm closed loop of the proximal duodenum in anaesthetized neonatal calves. The concentration and the output of the CCK activity in the duodenal perfusates increased significantly during pectrical stimulation of the vagus nerve, whereas the blood plasma concentration of CCK (external jugular vein and portal vein) remained unchanged and lower than that found in the duodenum. On the other hand, intravenous infusion of CCK raised the blood plasma but not the duodenal CCK concentrations. In conclusion, CCK-like activity is present in the duodenal lumen. The luminal release mechanism is at least partly regulated by the vagus nerves.

18

Development and regulation of pancreatic juice secretion in cattle. State-of-the-art

72%

Zabielski R., Pierzynowski S. G.

Journal of Animal and Feed Sciences

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2001

|

tom 10

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nr 1

19

Changes in the central respiratory rhythm following pharmacological blockade of the nucleus parabrachialis medialis in the rabbit

72%

Gromysz H.

Acta Neurobiologiae Experimentalis

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1997

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tom 57

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nr 4

20

Brain-gut axis in gastroprotection by leptin and cholecystokinin against ischemia-reperfusion induced gastric lesions

72%

Brzozowski T., Konturek P. C., Pajdo R., Kwiecien S., Ptak A., Sliwowski Z., Drozdowicz D., Pawlik M., Konturek S. J., Hahn E. G.

Journal of Physiology and Pharmacology

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2001

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tom 52

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nr 4,1

Leptin, a product of ob gene controlling food intake, has recently been detected in the stomach and shown to be released by CCK and implicated in gastroprotection against various noxious agents but it is unknown whether centrally applied leptin influences ischemia-reperfusion (I/R)-induced gastric erosions that progress into deeper gastric ulcerations. In this study we compared the effects of leptin and CCK-8 applied intracerebroventricularly (i.c.v.) or intraperitoneally (i.p.) on gastric mucosal lesions induced by I/R and topical application of 75% ethanol. Several major series of Wistar rats were used to examine the effects of leptin and CCK applied centrally on gastroprotection against I/R and ethanol in rats with A) vagotomy by cutting of vagal nerves, B) suppression of NO-synthase with L-NNA (20 mg/kg i.p.), C) inactivation of sensory nerves by capsaicin (125 mg/kg s.c.) and D) inhibition of CGRP receptors with CGRP8-37 (100 µg/kg i.p.) applied with or without the i.c.v. pretreatment with leptin or CCK-8. Rats were anesthetized 1 h after ethanol administration or at 3 h and 3 days upon the end of ischemia to measure the gastric blood flow (GBF) and then to determine the area of gastric lesions by planimetry. Blood was withdrawn for the measurement of plasma leptin and gastrin levels by radioimmunoassay (RIA). Leptin (0.1—20 µg/kg i.p.) dose-dependently attenuated gastric lesions induced by 75% ethanol and I/R; the dose reducing these lesions by 50% (ED50) was 8 µg/kg and 6 µg/kg, respectively and this protective effect was similar to that obtained with CCK-8 applied in a standard dose of 10 µg/kg i.p. This protective effect of leptin was accompanied by a significant increase in GBF and plasma gastrin levels whereas CCK-8 increased plasma leptin levels but failed to affect plasma gastrin levels. Leptin and CCK-8 applied i.c.v. in a dose of 625 ng/rat reduced significantly the area of I/R induced gastric lesions and raised the GBF and plasma leptin levels with the extent similar to those achieved with peripheral administration of leptin or CCK-8 (10 µg/kg i.p.). The protective and hyperemic effects of centrally administered leptin or CCK-8 (625 ng/rat i.c.v.) were completely abolished by vagotomy and significantly attenuated by sensory denervation with capsaicin or by CGRP antagonist, CGRP8-37. The pretreatment with L-NNA to inhibit NO-synthase activity attenuated significantly the protective and hyperemic effects of CCK but not those of leptin while capsaicin denervation counteracted leptin-- induced protection and rise in the GBF but attenuated significantly those of CCK. We conclude that: 1) central leptin exerts a potent gastroprotective activity against I/R-induced gastric erosions that progress into deeper gastric lesions and this protection depends upon vagal activity and sensory nerves and involves hyperemia probably mediated by NO and 2) leptin mimics the gastroprotective effect of CCK and may be implicated in the protective and hyperemic actions of this peptide against mucosal damage evoked by I/R.

Ograniczanie wyników

Effect of subdiaphragmatic vagotomy and cholinergic agents in the hypothalamic-pituitary-adrenal axis activity

Morphological examination of the proximal ganglion of the vagus nerve in the pig

Branches of the recurrent laryngeal nerves in the vicinity of the inferior thyroid arteries

Increase of cardiodepressant activity in medium incubating the posterior pituitary lobe in situ during vagal nerve stimulation in rat

The ghrelin pentapeptide inhibits the secretion of pancreatic juice in rats

Involvement of vagal opioid receptors in respiratory effects of morphine in an anaesthetized rats

Capsaicin induced deafferentiation enhances the effect of electrical vagal nerve stimulation on food intake and body mass

Measurements of the Obersteiner-Redlich zone of the vagus nerve and their possible clinical applications

Influence of vagal nerve stimulation on food intake and body weight - results of experimental studies

Morphology and development of depressive nerve (nervus depressor) of pig at prenatal stage

Luminal CCK and its neuronal action on exocrine pancreatic secretion

Scanning electron microscope analysis of the distal vagus nerve ganglion (ganglion distale nervi vagi) in newborn calves in standard husbandry

Short-term depression of inspiratory activity following tonic vagal stimulation

Komorki zwojowe w nerwach blednych swini domowej

The structure and topography of the parasympathetic and the ambiguous nuclei of the glossopharyngeal and vagus nerves in the goose [Anser anser]

Central and peripheral neural control of pancreatic exocrine secretion

Cholecystokinin-like activity in the duodenal lumen of anaesthetized neonatal calves

Development and regulation of pancreatic juice secretion in cattle. State-of-the-art

Changes in the central respiratory rhythm following pharmacological blockade of the nucleus parabrachialis medialis in the rabbit