Physiological enteric stimulation elicits cardiovascular reflexes in the rat

By use of anesthetized rats, parameters for the activation of cardiovascular reflexes by stimulation of gastric or hepatic receptors have been established. For reflex activation, the mean minimum intragastric volume was 4 ml, and the mean minimum rate of hepatic portal vein infusion was 0.3 ml/min. Subdiaphragmatic vagotomy affected the response to gastric distension but did not appear to affect the response to hepatic portal vein infusion, indicating that vagal afferents are involved in mediating gastric-cardiovascular but not hepatic-cardiovascular reflexes. Experiments designed to emphasize the vagal component of the response to gastric distension confirmed this finding. Antagonist effects indicated that the tachycardia was mediated by beta-adrenoreceptor stimulation and that the pressor response was mainly mediated by alpha-adrenoreceptors. The data show that stimuli used in experiments to assess central processing of sensory information from the gastrointestinal tract can activate cardiovascular reflexes. Caution in the design of such experiments and in the interpretation of the data generated is indicated.

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Convergence of sensory information from abdominal viscera in the rat brain stem

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1986.251.2.g169 ◽

1986 ◽

Vol 251 (2) ◽

pp. G169-G175 ◽

Cited By ~ 7

Author(s):

F. Appia ◽

W. R. Ewart ◽

B. S. Pittam ◽

D. L. Wingate

Keyword(s):

Portal Vein ◽

Brain Stem ◽

Rat Brain ◽

Sensory Information ◽

Vagal Afferents ◽

Gastric Distension ◽

Significant Difference ◽

Hepatic Portal Vein ◽

Hepatic Portal ◽

Portal Vein Infusion

This study was carried out to establish whether there was convergence of sensory information in the rat brain stem stimulated by physiological activation of gastric mechanoreceptors and hepatic glucoreceptors. Extracellular recordings were made from single neurons in the region of the dorsal vagal nucleus and nucleus of the solitary tract in the medulla. The responses of these neurons to gastric distension, hepatic portal vein perfusion of isotonic D-glucose, and hepatic portal vein infusion of isotonic saline were studied. Fifty-six neurons were studied; it was found that there was no significant difference in the proportion of neurons responding to gastric distension compared with the number responding to either form of hepatic stimulation. In 20 neurons (all 3 types of stimulation were tested on the same neuron), both excitation and inhibition were observed with both forms of visceral stimulation. Of the seven of these neurons that responded to hepatic portal vein infusion, four of them also had an input from gastric mechanoreceptors. Only three of the neurons that responded to hepatic stimulation showed a specific response to hepatic glucose perfusion; in the remainder a component of the response was due to the infusion of the volume itself. The results from these experiments have demonstrated an apparently weak functional synaptic projection carried by hepatic vagal afferents, particularly those responding to changes in portal glucose concentration, which may indicate a rather diffuse and nonspecific sensory system in the liver. These results have also demonstrated the convergence onto neurons in the brain stem of information from gastric and hepatic enteroceptors.(ABSTRACT TRUNCATED AT 250 WORDS)

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EXTRA-HEPATIC PART OF PORTAL VEIN – A CADAVERIC STUDY IN ADULTS & FOETUSES

10.36106/ijar/3107836 ◽

2021 ◽

pp. 7-9

Author(s):

Seena N ◽

Lekha K S ◽

Arivuselvan S

Keyword(s):

Portal Vein ◽

Common Type ◽

Type I ◽

Left Gastric Vein ◽

Portal Vein Anatomy ◽

Hepatic Portal Vein ◽

The Mean ◽

Hepatic Portal ◽

The Right ◽

Upper Abdomen

Background: Variations of the Hepatic Portal Vein are encountered during abdominal surgeries. Aim: The present study is an observational study of the extrahepatic part of Portal Vein & its variations on cadavers. Materials & Methods: A total of 50 upper abdomen dissections were carried out to delineate extra-hepatic Portal Vein anatomy. The Results: mean length of Portal Vein was 5.96cm. The mean diameter of Portal Vein was 1.35cm. The most common type of formation of Portal Vein was Type I, found in 64%. The Right Gastric Vein commonly emptied into the trunk of the Portal Vein. The Left Gastric Vein commonly emptied into the trunk of the Portal Vein in 87.18%. The most common type of Portal Vein termination was Extra-Hepatic, found in 76% of 50 dissections. The Bifurcation pattern was the most common pattern of Portal Vein termination, found in 94% of dissections. The ndings of the present Conclusion: study highlight the variations that may occur in the hepatic portal venous system in its extra-hepatic part. Sound knowledge of portal venous anatomy is needed for success in the surgeries of the liver & adjacent viscera.

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Hepatic portal vein infusion of glucose and sodium solutions on the control of saline drinking in the rat.

The Journal of Physiology ◽

10.1113/jphysiol.1978.sp012138 ◽

1978 ◽

Vol 274 (1) ◽

pp. 129-139 ◽

Cited By ~ 41

Author(s):

W D Blake ◽

K K Lin

Keyword(s):

Portal Vein ◽

Hepatic Portal Vein ◽

Hepatic Portal ◽

Portal Vein Infusion

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Hepatic contribution to satiation of salt appetite in rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1986.251.6.r1095 ◽

1986 ◽

Vol 251 (6) ◽

pp. R1095-R1102 ◽

Cited By ~ 6

Author(s):

M. G. Tordoff ◽

J. Schulkin ◽

M. I. Friedman

Keyword(s):

Portal Vein ◽

Sodium Concentration ◽

Reciprocal Relationship ◽

Dietary Sodium ◽

Salt Appetite ◽

Nacl Solution ◽

Hepatic Portal Vein ◽

Hepatic Portal ◽

Portal Vein Infusion ◽

The Brain

We examined the influence of hepatic-portal vein infusion of NaCl and of hepatic vagotomy on 3% NaCl solution drinking by sodium-deficient rats. Combined dietary sodium restriction and administration of the natriuretic agent, furosemide (5 mg), produced a vigorous appetite for 3% NaCl solution that was attenuated by portal infusion of NaCl. Whereas infusions (1 ml/30 min) of NaCl into the hepatic-portal vein in concentrations as low as 0.15 M (isotonic) significantly reduced 3% NaCl consumption, a higher concentration (0.6 M) infused into the jugular vein, or portal infusions of KCl (0.6 M) or sucrose (1.2 M), were ineffective. Rats with selective hepatic vagotomy displayed an attenuated appetite for salt whether or not they received hepatic-portal NaCl. This was not due to altered excretion of sodium. Taken together, these results suggest that the liver or portal vein can provide a sodium-specific neural signal capable of attenuating the appetite for salt and this information is transferred to the brain by fibers in the hepatic vagus that fire in reciprocal relationship with portal sodium concentration.

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Growth assessment in children with extra-hepatic portal vein obstruction and portal hypertension

Arquivos de Gastroenterologia ◽

10.1590/s0004-28032003000400009 ◽

2003 ◽

Vol 40 (4) ◽

pp. 247-250 ◽

Cited By ~ 14

Author(s):

Maria Angela Bellomo-Brandão ◽

André Moreno Morcillo ◽

Gabriel Hessel ◽

Silvia Regina Cardoso ◽

Maria de Fátima P. C. Servidoni ◽

...

Keyword(s):

Body Mass Index ◽

Portal Hypertension ◽

Portal Vein ◽

Portal Vein Obstruction ◽

Z Scores ◽

Hepatic Portal Vein ◽

The Mean ◽

Hepatic Portal ◽

Height For Age ◽

Weight For Age

BACKGROUND: Several studies carried out to examine the growth of children with extra-hepatic portal vein obstruction and portal hypertension have reported a variety of findings. AIM: To assess anthropometric indices in children with portal hypertension due to extra-hepatic portal vein obstruction and who were treated by endoscopic variceal sclerotherapy. METHODS: Anthropometric data were obtained retrospectively from the medical records of 24 patients who had been followed for 3.8 ± 2.5 years at the Pediatric Gastroenterology Outpatient Clinic of the University Hospital, Campinas, SP, Brazil. The mean Z scores of weight for age, height for age and body mass index at diagnosis and at the last consultation were compared to reference data of the National Center for Health Statistics. The two recordings were compared to assess the long-term effect of the condition. RESULTS: The mean Z scores at diagnosis and at the last follow-up visit were all within normal ranges when compared to the reference population, with the following respective values: weight for age, 0.042 ± 1.09 and 0.132 ± 1.29; height for age, 0.200 ± 1.04 and 0.466 ± 1.24, and body mass index, -0.223 ± 0.98 and -0.198 ± 0.98. In addition, there were no significant differences between the Z score values obtained in the two recordings. CONCLUSION: Portal hypertension due to extra-hepatic portal vein obstruction was not associated with growth impairment in the group of children studied.

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Influence of the Rate of Hepatic Portal Vein Infusion on Hexobarbital Pharmacokinetics in the Rat

Pharmacology ◽

10.1159/000138386 ◽

1988 ◽

Vol 36 (3) ◽

pp. 210-216 ◽

Cited By ~ 1

Author(s):

Rolf P. Joeres ◽

Nico P.E. Vermeulen ◽

Douwe D. Breimer

Keyword(s):

Portal Vein ◽

Hepatic Portal Vein ◽

Hepatic Portal ◽

Portal Vein Infusion

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ASSESSMENT OF NORMAL LIVER PORTAL VEIN AND COMMON BILE DUCT USING DOPPLER ULTRASONOGRAPHY

International Journal of Research -GRANTHAALAYAH ◽

10.29121/granthaalayah.v6.i11.2018.1141 ◽

2018 ◽

Vol 6 (11) ◽

pp. 384-390

Author(s):

Ashraf Mustafa ◽

Mohamad Elfadi ◽

Mohamed Gar Elnabi ◽

Mona Ahmed ◽

Abdelmoneim Sulieman

Keyword(s):

Bile Duct ◽

Common Bile Duct ◽

Portal Vein ◽

Doppler Ultrasonography ◽

Normal Liver ◽

Vital Role ◽

Hepatic Portal Vein ◽

The Mean ◽

Hepatic Portal ◽

Age Range

Ultrasound imaging plays a vital role in the evaluation of many tissue or organs disorder. The objective of this study was to evaluate normal liver portal vein (PV) and common bile duct (CBD) using Doppler Ultrasonography (Duplex). Two ultrasound machines equipped with linear and curvilinear probes used in this study (Toshiba and ALOKA, Japan) during the period from 1st April 2016 to 30th July 2017. A total of 300 (48% males; 52% females) healthy subjects were participated in this study with age range from 16-22 years old. The mean intrahepatic portal vein velocity is between (14.98±1.92) cm/s; and the diameter range is (9.76±2.09). In frequency distribution of the extrahepatic portal vein velocity values, the majority is in the range (14-15 cm/s) which is equal to the half of the examined subjects. The extra hepatic PV versus intra hepatic portal vein velocities was found to be more in normal liver, where the velocity increased by 0.31 cm/s inside the liver per each cm/s of the extrahepatic for the normal liver.

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