open access

Ahead of Print
Original article
Published online: 2021-02-23
Submitted: 2020-12-24
Accepted: 2021-02-01
Get Citation

Identification of hepatosensitive region and their neural connections in the hippocampus of rats

Z. Cheng, R. Wei, N. Cao, Z. Li, M. Li, M. Liu, L. Zhu, C. Xia
DOI: 10.5603/FM.a2021.0020
·
Pubmed: 33634834

open access

Ahead of Print
ORIGINAL ARTICLES
Published online: 2021-02-23
Submitted: 2020-12-24
Accepted: 2021-02-01

Abstract

Background: Visceral function localization of the brain is very complex. For many years, people have been actively exploring the neural mechanism regulating visceral and substance metabolism, clarifying the complex relationship between the brain and peripheral nervous system related to the regulation of visceral activity, and analyzing its complex neural pathways. The brain is the advanced center of visceral function regulation. As an advanced center for substance metabolism and visceral regulation, the hippocampus is crucial for regulating visceral function. The liver is the core organ of material metabolism, and its afferent signals are mainly projected to the Nucleus of the solitary tract(NTS) through vagus nerve, and then they are projected to the hypothalamus and limbic system. Materials and methods: We placed a stereotaxic instrument on the head of each rat and performed craniotomy to open a window above the left hippocampus. We used gold-plated tungsten electrodes to monitor hippocampal neuronal discharges. Grounding was achieved using screws and silver wire. We electrically stimulated the liver branch of the vagus nerve and observed changes in hippocampal neuron discharges using a biological method; in this way, we identified hepatosensitive hippocampal region. We injected FluoroGold into this region and related brain areas. After 3 days, the rats were sacrificed and perfused; the hippocampi were fixed, dehydated, frozen, sectioned, and subjected to fluorescence microscopy. Results: Nerve discharge frequency and amplitude significantly increased in the hippocampal CA3 region (AP: -4.9, ML: -5.1, DV: -5.0 mm). After FluoroGold was injected into the left hepatosensitive region  in the hippocampus, labeled cells were found in the contralateral hippocampus, ipsilateral piriform cortex (PC), locus coeruleus (LC) and bilateral lateral hypothalamus (LHA); fluorescence in the ipsilateral hypothalamus was stronger than that of the contralateral hypothalamus. FluoroGold was injected into the LHA, PC, and LC; no labeled cells were found in the hippocampal CA3 region or in the control group. Conclusions: The hippocampal CA3 area of rats may contain a hepatosensitive region that plays important roles in the regulation of liver and other organ function. These region may receive input from the LHA, PC, and LC.

Abstract

Background: Visceral function localization of the brain is very complex. For many years, people have been actively exploring the neural mechanism regulating visceral and substance metabolism, clarifying the complex relationship between the brain and peripheral nervous system related to the regulation of visceral activity, and analyzing its complex neural pathways. The brain is the advanced center of visceral function regulation. As an advanced center for substance metabolism and visceral regulation, the hippocampus is crucial for regulating visceral function. The liver is the core organ of material metabolism, and its afferent signals are mainly projected to the Nucleus of the solitary tract(NTS) through vagus nerve, and then they are projected to the hypothalamus and limbic system. Materials and methods: We placed a stereotaxic instrument on the head of each rat and performed craniotomy to open a window above the left hippocampus. We used gold-plated tungsten electrodes to monitor hippocampal neuronal discharges. Grounding was achieved using screws and silver wire. We electrically stimulated the liver branch of the vagus nerve and observed changes in hippocampal neuron discharges using a biological method; in this way, we identified hepatosensitive hippocampal region. We injected FluoroGold into this region and related brain areas. After 3 days, the rats were sacrificed and perfused; the hippocampi were fixed, dehydated, frozen, sectioned, and subjected to fluorescence microscopy. Results: Nerve discharge frequency and amplitude significantly increased in the hippocampal CA3 region (AP: -4.9, ML: -5.1, DV: -5.0 mm). After FluoroGold was injected into the left hepatosensitive region  in the hippocampus, labeled cells were found in the contralateral hippocampus, ipsilateral piriform cortex (PC), locus coeruleus (LC) and bilateral lateral hypothalamus (LHA); fluorescence in the ipsilateral hypothalamus was stronger than that of the contralateral hypothalamus. FluoroGold was injected into the LHA, PC, and LC; no labeled cells were found in the hippocampal CA3 region or in the control group. Conclusions: The hippocampal CA3 area of rats may contain a hepatosensitive region that plays important roles in the regulation of liver and other organ function. These region may receive input from the LHA, PC, and LC.

Get Citation

Keywords

neural regulation of liver function, hepatic branch of the vagus nerve, hippocampus, neural pathways

About this article
Title

Identification of hepatosensitive region and their neural connections in the hippocampus of rats

Journal

Folia Morphologica

Issue

Ahead of Print

Article type

Original article

Published online

2021-02-23

DOI

10.5603/FM.a2021.0020

Pubmed

33634834

Keywords

neural regulation of liver function
hepatic branch of the vagus nerve
hippocampus
neural pathways

Authors

Z. Cheng
R. Wei
N. Cao
Z. Li
M. Li
M. Liu
L. Zhu
C. Xia

Important: This website uses cookies. More >>

The cookies allow us to identify your computer and find out details about your last visit. They remembering whether you've visited the site before, so that you remain logged in - or to help us work out how many new website visitors we get each month. Most internet browsers accept cookies automatically, but you can change the settings of your browser to erase cookies or prevent automatic acceptance if you prefer.

By  "Via Medica sp. z o.o." sp.k., Świętokrzyska 73, 80–180 Gdańsk, Poland

tel.:+48 58 320 94 94, faks:+48 58 320 94 60, e-mail:  viamedica@viamedica.pl