Post-traumatic stress disorder (PTSD) has been reported to be associated with a higher risk of cardiovascular disease. The amygdala may have an important role in regulating cardiovascular function. This study aims to explore the effect of amygdala glutamate receptors (GluRs) on cardiovascular activity in a rat model of PTSD. A compound stress method combining electrical stimulation and single prolonged stress was used to prepare the PTSD model, and the difference of weight gain before and after modeling and the elevated plus maze were used to assess the PTSD model. In addition, the distribution of retrogradely labeled neurons was observed using the FluoroGold (FG) retrograde tracking technique. Western blot was used to analyze the changes of amygdala GluRs content. To further investigate the effects, artificial cerebrospinal fluid (ACSF), non-selective GluR blocker kynurenic acid (KYN) and AMPA receptor blocker CNQX were microinjected into the central nucleus of the amygdala (CeA) in the PTSD rats, respectively. The changes in various indices following the injection were observed using in vivo multi-channel synchronous recording technology. The results indicated that, compared with the control group, the PTSD group exhibited significantly lower weight gain (P < 0.01) and significantly decreased ratio of open arm time (OT%) (P < 0.05). Retrograde labeling of neurons was observed in the CeA after microinjection of 0.5 µL FG in the rostral ventrolateral medulla (RVLM). The content of AMPA receptor in the PTSD group was lower than that in the control group (P < 0.05), while there was no significant differences in RVLM neuron firing frequency and heart rate (P > 0.05) following ACSF injection. However, increases in RVLM neuron firing frequency and heart rate were observed after the injection of KYN or CNQX into the CeA (P < 0.05) in the PTSD group. These findings suggest that AMPA receptors in the amygdala are engaged in the regulation of cardiovascular activity in PTSD rats, possibly by acting on inhibitory pathways.
Rats ; Animals ; Rats, Sprague-Dawley ; Stress Disorders, Post-Traumatic ; Receptors, AMPA ; 6-Cyano-7-nitroquinoxaline-2,3-dione/pharmacology* ; Receptors, Glutamate/metabolism* ; Amygdala ; Weight Gain ; Medulla Oblongata/physiology* ; Blood Pressure

The nucleus tractus solitarii (NTS) is one of the morphologically and functionally defined centers that engage in the autonomic regulation of cardiovascular activity. Phenotypically-characterized NTS neurons have been implicated in the differential regulation of blood pressure (BP). Here, we investigated whether phenylethanolamine N-methyltransferase (PNMT)-expressing NTS (NTS^PNMT) neurons contribute to the control of BP. We demonstrate that photostimulation of NTS^PNMT neurons has variable effects on BP. A depressor response was produced during optogenetic stimulation of NTS^PNMT neurons projecting to the paraventricular nucleus of the hypothalamus, lateral parabrachial nucleus, and caudal ventrolateral medulla. Conversely, photostimulation of NTS^PNMT neurons projecting to the rostral ventrolateral medulla produced a robust pressor response and bradycardia. In addition, genetic ablation of both NTS^PNMT neurons and those projecting to the rostral ventrolateral medulla impaired the arterial baroreflex. Overall, we revealed the neuronal phenotype- and circuit-specific mechanisms underlying the contribution of NTS^PNMT neurons to the regulation of BP.
Solitary Nucleus/metabolism* ; Blood Pressure/physiology* ; Phenylethanolamine N-Methyltransferase/metabolism* ; Neurons/metabolism* ; Paraventricular Hypothalamic Nucleus/metabolism*

Objective: To investigate the misdiagnosis of area postrema syndrome (APS) manifesting as intractable nausea, vomiting and hiccups in neuromyelitis optic spectrum disease (NMOSD) and reduce the risk of misdiagnosis. Methods: We retrospectively analyzed data from NMOSD patients attending the Department of Neurology at the First Medical Center of PLA General Hospital between January 2019 and July 2021. SPSS25.0 was then used to analyze the manifestations, misdiagnosis, and mistreatment of APS. Results: A total of 207 patients with NMOSD were included, including 21 males and 186 females. The mean age of onset was 39±15 years (range: 5-72 years). The proportion of patients who were positive for serum aquaporin 4 antibody was 82.6% (171/207). In total, 35.7% (74/207) of the NMOSD patients experienced APS during the disease course; of these patients, 70.3% (52/74) had APS as the first symptom and 29.7% (22/74) had APS as a secondary symptom. The misdiagnosis rates for these conditions were 90.4% (47/52) and 50.0% (11/22), respectively. As the first symptom, 19.2% (10/52) of patients during APS presented only with intractable nausea, vomiting and hiccups; 80.8% (42/52) of patients experienced other neurological symptoms. The Departments of Gastroenterology and General Medicine were the departments that most frequently made the first diagnosis of APS, accounting for 54.1% and 17.6% of patients, respectively. The most common misdiagnoses related to diseases of the digestive system and the median duration of misdiagnosis was 37 days. Conclusions: APS is a common symptom of NMOSD and is associated with a high rate of misdiagnosis. Other concomitant symptoms often occur with APS. Gaining an increased awareness of this disease/syndrome, obtaining a detailed patient history, and performing physical examinations are essential if we are to reduce and avoid misdiagnosis.
Male ; Female ; Humans ; Child, Preschool ; Child ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged ; Neuromyelitis Optica/diagnosis* ; Area Postrema ; Retrospective Studies ; Hiccup/complications* ; Vomiting/etiology* ; Nausea/etiology* ; Inflammation ; Syndrome ; Autoantibodies ; Diagnostic Errors ; Aquaporin 4

Humans ; Child ; Sleep Apnea Syndromes/complications* ; Medulla Oblongata/pathology* ; Neoplasms/complications*

Objective To examine the neuroanatomical substrates underlying the effects of minocycline in alleviating lipopolysaccharide (LPS)-induced neuroinflammation. Methods Forty C57BL/6 male mice were randomly and equally divided into eight groups. Over three conse-cutive days, saline was administered to four groups of mice and minocycline to the other four groups. Immediately after the administration of saline or minocycline on the third day, two groups of mice were additionally injected with saline and the other two groups were injected with LPS. Six or 24 hours after the last injection, mice were sacrificed and the brains were removed. Immunohistochemical staining across the whole brain was performed to detect microglia activation via Iba1 and neuronal activation via c-Fos. Morphology of microglia and the number of c-Fo-positive neurons were analyzed by Image-Pro Premier 3D. One-way ANOVA and Fisher's least-significant differences were employed for statistical analyses. Results Minocycline alleviated LPS-induced neuroinflammation as evidenced by reduced activation of microglia in multiple brain regions, including the shell part of the nucleus accumbens (Acbs), paraventricular nucleus (PVN) of the hypothalamus, central nucleus of the amygdala (CeA), locus coeruleus (LC), and nucleus tractus solitarius (NTS). Minocycline significantly increased the number of c-Fo-positive neurons in NTS and area postrema (AP) after LPS treatment. Furthermore, in NTS-associated brain areas, including LC, lateral parabrachial nucleus (LPB), periaqueductal gray (PAG), dorsal raphe nucleus (DR), amygdala, PVN, and bed nucleus of the stria terminali (BNST), minocycline also significantly increased the number of c-Fo-positive neurons after LPS administration. Conclusion Minocycline alleviates LPS-induced neuroinflammation in multiple brain regions, possibly due to increased activation of neurons in the NTS-associated network.
Animals ; Female ; Lipopolysaccharides/toxicity* ; Male ; Mice ; Mice, Inbred C57BL ; Minocycline/pharmacology* ; Neuroinflammatory Diseases ; Solitary Nucleus

Leptin, an adipocyte-derived peptide hormone, has been shown to facilitate breathing. However, the central sites and circuit mechanisms underlying the respiratory effects of leptin remain incompletely understood. The present study aimed to address whether neurons expressing leptin receptor b (LepRb) in the nucleus tractus solitarii (NTS) contribute to respiratory control. Both chemogenetic and optogenetic stimulation of LepRb-expressing NTS (NTS^LepRb) neurons notably activated breathing. Moreover, stimulation of NTS^LepRb neurons projecting to the lateral parabrachial nucleus (LPBN) not only remarkably increased basal ventilation to a level similar to that of the stimulation of all NTS^LepRb neurons, but also activated LPBN neurons projecting to the preBötzinger complex (preBötC). By contrast, ablation of NTS^LepRb neurons projecting to the LPBN notably eliminated the enhanced respiratory effect induced by NTS^LepRb neuron stimulation. In brainstem slices, bath application of leptin rapidly depolarized the membrane potential, increased the spontaneous firing rate, and accelerated the Ca²⁺ transients in most NTS^LepRb neurons. Therefore, leptin potentiates breathing in the NTS most likely via an NTS-LPBN-preBötC circuit.
Leptin/pharmacology* ; Membrane Potentials ; Neurons/metabolism* ; Solitary Nucleus/metabolism*

This paper introduces GAO Wei-bin's academic thought in treatment of medulla oblongata paralysis with acupuncture. Through analyzing the etiologies and locations of medulla oblongata paralysis, in accordance with "selecting the nearby acupoints of the affected area", the acupoints are selected from the nape region, the nape acupuncture therapy and the corresponding new points are developed. Based on the human anatomy of the nape region, the anatomic structures of new points (e.g. Gongxue, Tunyan-1, Tunyan-2, Fayin, Zhiqiang and Tiyan) and their effect mechanism are explained. The treatment principle, "distinguishing the symptoms from the root causes, mutual treatment for both symptoms and root causes", is proposed, and the importance of electric stimulation of nape acupuncture is suggested in treatment of medulla oblongata paralysis.
Humans ; Acupuncture ; Acupuncture Therapy ; Acupuncture Points ; Bulbar Palsy, Progressive/therapy* ; Medulla Oblongata ; Paralysis

Accumulating evidence demonstrates that the nucleus tractus solitarii (NTS) neurons serve as central respiratory chemoreceptors, but the underlying molecular mechanisms remain undefined. The present study investigated the expression of acid-sensitive ether-à-go-go-gene-like (Elk, Kv12) channels in the NTS of mice. Immunofluorescence staining was used to observe the distribution and cellular localization of the Kv12 channels in NTS neurons. Western blot and quantitative real-time PCR (qPCR) were used to evaluate protein and mRNA expression levels of Kv12 channels. The results showed that all of the three members (Kv12.1, Kv12.2, Kv12.3) of the Kv12 channel family were expressed in NTS neurons, and their expressions were co-localized with paired-like homeobox 2b gene (Phox2b) expression. The expression of Kv12.1 mRNA was the largest, whereas the expression of Kv12.3 was the least in the NTS. The results suggest Kv12 channels are expressed in Phox2b-expressing neurons in the NTS of mice, which provides molecular evidence for pH sensitivity in Phox2b-expressing NTS neurons.
Animals ; Mice ; Neurons ; Potassium Channels, Voltage-Gated ; Solitary Nucleus ; Transcription Factors/genetics*

This study was aimed to investigate the cardiovascular function in rats with post-traumatic stress disorder (PTSD) and the potential association with the activities of the rostral ventrolateral medulla (RVLM) and the medial habenular nucleus (MHb). Multi-channel in vivo recordings were used to simultaneously acquire spontaneous neuronal firing and peripheral physiological indices, and FluoroGold (FG) retrograde tracing technique was used to observe the projections of labeled neurons in the MHb. The results showed that the discharge frequency of RVLM and MHb neurons, the systolic blood pressure (SBP), and the mean arterial pressure (MAP) in the PTSD group were all increased significantly compared with those in control group (P < 0.05). MHb neurons were retrogradely labeled by FG through microinjection (4% FG, 0.5 μL) into the RVLM. In the control group, electrical stimulation in the MHb increased heart rate (HR) at 100-300 μA (P < 0.05), elevated SBP and MAP at 200-300 μA (P < 0.05), and remarkably increased the RVLM neuronal discharge frequency at 100-500 μA (P < 0.05 or P < 0.01). In the PTSD group, however, only the discharge frequency of RVLM neurons was increased by the electrical stimulation at 100-300 μA (P < 0.05). These results suggest that cardiovascular activities of the PTSD model rat are enhanced, and this change may be related to the activity changes of RVLM and MHb and the potential connection between the two nuclei.
Animals ; Blood Pressure ; Medulla Oblongata ; Neurons ; Rats ; Rats, Sprague-Dawley ; Stress Disorders, Post-Traumatic

Humans ; Neurons ; Olivary Nucleus ; Superior Olivary Complex