Acute effects of glossopharyngeal insufflation in people with cervical spinal cord injury.

OBJECTIVES: To evaluate acute effects of glossopharyngeal insufflation (GI) on lung function, airway pressure (Paw), blood pressure and heart rate (HR) in people with cervical spinal cord injury (CSCI). DESIGN: Case-control design. SETTING: Karolinska Institutet, Stockholm, Sweden. PARTICIPANTS: Ten participants with CSCI suffering from lesions between C4 and C8, and ASIA classification of A or B were recruited. Ten healthy particpants familiar with GI were recruited as a reference group. OUTCOME MEASURES: Spirometry, mean arterial blood pressure (MAP), Paw, and HR were measured in a sitting and a supine position before, during, and after GI. RESULTS: GI in the study group in a sitting position increased total lung capacity (TLC) by 712 ml: P < 0.001, vital capacity (VC) by 587 ml: P < 0.0001, Paw by 13 cm H2O: P < 0.01, and HR by 10 beats/min: P < 0.001. MAP decreased by 25 mmHg, P < 0.0001. Significant differences were observed between groups comparing baseline with GI. The reference group had a higher increase in; TLC (P < 0.01), VC (P < 0.001), Paw (P < 0.001) and HR (P < 0.05) and a higher decrease in MAP (P < 0.001). With GI in a sitting compared to a supine position, TLC, MAP, HR, Paw remained unchanged in the study group, while residual volume decreased in the supine position (P < 0.01). CONCLUSION: There was a difference between the groups in the increase in TLC; VC; Paw, HR and in the decrease in MAP with GI, however MAP, HR and Paw responded in similar way in both groups in a sitting as well as a supine position. If performed correctly, the risks of GI resulting in clinically significant hemodynamic changes is low, although syncope may still occur.

Fetal alcohol exposure reduces responsiveness of taste nerves and trigeminal chemosensory neurons to ethanol and its flavor components.

Fetal alcohol exposure (FAE) leads to increased intake of ethanol in adolescent rats and humans. We asked whether these behavioral changes may be mediated in part by changes in responsiveness of the peripheral taste and oral trigeminal systems. We exposed the experimental rats to ethanol in utero by administering ethanol to dams through a liquid diet; we exposed the control rats to an isocaloric and isonutritive liquid diet. To assess taste responsiveness, we recorded responses of the chorda tympani (CT) and glossopharyngeal (GL) nerves to lingual stimulation with ethanol, quinine, sucrose, and NaCl. To assess trigeminal responsiveness, we measured changes in calcium levels of isolated trigeminal ganglion (TG) neurons during stimulation with ethanol, capsaicin, mustard oil, and KCl. Compared with adolescent control rats, the adolescent experimental rats exhibited diminished CT nerve responses to ethanol, quinine, and sucrose and GL nerve responses to quinine and sucrose. The reductions in taste responsiveness persisted into adulthood for quinine but not for any of the other stimuli. Adolescent experimental rats also exhibited reduced TG neuron responses to ethanol, capsaicin, and mustard oil. The lack of change in responsiveness of the taste nerves to NaCl and the TG neurons to KCl indicates that FAE altered only a subset of the response pathways within each chemosensory system. We propose that FAE reprograms development of the peripheral taste and trigeminal systems in ways that reduce their responsiveness to ethanol and surrogates for its pleasant (i.e., sweet) and unpleasant (i.e., bitterness, oral burning) flavor attributes.NEW & NOTEWORTHY Pregnant mothers are advised to avoid alcohol. This is because even small amounts of alcohol can alter fetal brain development and increase the risk of adolescent alcohol abuse. We asked how fetal alcohol exposure (FAE) produces the latter effect in adolescent rats by measuring responsiveness of taste nerves and trigeminal chemosensory neurons. We found that FAE substantially reduced taste and trigeminal responsiveness to ethanol and its flavor components.

UPPER AIRWAY BLOCKS FOR AWAKE DIFFICULT AIRWAY MANAGEMENT.

Airway anesthesia is pivotal for successful awake intubation provided either topically or by blocks. Airway blocks are considered technically more difficult to perform and carry a higher risk of complications. However, in experienced hands, they can be useful as they provide excellent intubating conditions. For complete upper airway anesthesia, bilateral glossopharyngeal and superior laryngeal nerve blocks with translaryngeal injection are required. Superior laryngeal nerve block and translaryngeal injection can be performed easily, safely and with a high success rate in patients with normal anatomy. In those with difficult landmarks, ultrasound can be of assistance. For the superior laryngeal nerve block, other targets than the nerve itself must be established to make the technique consistently successful, easy to teach, learn and perform. The same applies to the translaryngeal injection, where the use of ultrasound is necessary for correct midline identification. Intraoral glossopharyngeal nerve block is also safe and easy to perform, but associated with long lasting discomfort. Bilateral extraoral peristyloid approach should be discouraged since inadvertent blocks of the closely adjacent vagus nerve cannot be prevented in this location. A safe and easy method of blocking the distal portions of the glossopharyngeal nerve for awake intubation is therefore required.

Concentration and state dependent reductions in corn oil intakes after glossopharyngeal nerve transections in rats.

Previous studies indicate a role for the glossopharyngeal nerve (GL) in the detection of dietary fats. The present experiments examined the effects of bilateral glossopharyngeal nerve transections (GLx) on the intake of low (4.8%), moderate (16%), and full-fat (100%) corn oil in non-deprived, food-deprived, and water-deprived rats. The rats had access to oils, 0.3 M sucrose, and water in a gustometer that measured number of licks and latency to the first lick during brief access trials. The behavioral measures were used as indices of the amount consumed and the motivation to ingest, respectively. After baseline intakes had stabilized, the rats received GLx or sham transections (Sham) and were then re-tested. Pre and post-surgery responses were compared to determine the impact of GLx on intake and the motivation to ingest. In non-deprived rats, GLx reduced the intake of 4.8% and 16% oils and decreased the motivation to ingest these oils. In food-deprived rats, GLx prevented increases in the ingestion of 4.8% and 16% oils and in the motivation to ingest these oils. In water-deprived rats, GLx reduced the intake of 100% oil and produced a general decrease in the motivation to consume low, moderate, and full-fat emulsions. These results indicate that GL is partially involved in corn oil intake and suggest an interactive effect of oil concentration with homeostatic state.

Independent cough flow augmentation by glossopharyngeal breathing plus table thrust in muscular dystrophy.

OBJECTIVE: The purpose of the present study was to compare the unassisted cough peak flow (CPF) of patients affected by muscular dystrophy with CPF augmented by various techniques, including maximal depth glossopharyngeal breathing (GPB) combined with a subsequent self-induced thoracic or abdominal thrust. DESIGN: All of the motorized wheelchair-dependent patients with muscular dystrophy who had previously mastered GPB were trained at home to increase their cough efficacy. This training involved maneuvering their wheelchair against the edge of a specially built table to autonomously produce a thoracic and/or abdominal thrust timed to the opening of the glottis for an independently assisted cough. Both unassisted and variously assisted CPFs were compared. RESULTS: The 18 patients (17 men/1 woman) with muscular dystrophy, aged 21.1 ± 5.4 yrs, achieved variously assisted CPFs that were significantly higher than the spontaneous CPF (P < 0.001), with assisted CPFs but not unassisted CPFs that significantly exceeded a reported efficacious cough threshold value of 160 liters/min (P < 0.001). Moreover, increases in the CPFs by personal assistance including air stacking by manual resuscitator and thoracoabdominal thrust (326.4 ± 79.5 liters/min) or by GPB and thoracoabdominal thrust (326.4 ± 87.5 liters/min) were not significantly different (P = 0.07) from the CPFs independently attained by GPB plus independently maneuvering a wheelchair for a table thrust (310.3 ± 74.7 liters/min). CONCLUSIONS: The independently assisted (GPB plus table thrust) CPF was comparable to the CPFs that required personal assistance for air stacking and abdominal thrusts. Therefore, for patients with muscular dystrophy, this physical medicine technique and cough-assisted techniques that require personal intervention are strongly recommended.

Necessity of the glossopharyngeal nerve in the maintenance of normal intake and ingestive bout size of corn oil by rats.

Recent evidence in the literature suggests that signals carried by the glossopharyngeal nerve (GL), which supplies sensory and parasympathetic innervation of the posterior tongue, might be essential in the maintenance of normal gustatory responses to fat stimuli. Here, we report that GL transection (GLX) significantly decreased corn oil intake and preference in 23-h two-bottle tests relative to sham-operated controls (Sham). Drinking-pattern analysis of corn oil licking revealed that bout size, rather than the number of bouts initiated, was smaller in GLX than Sham rats. We also tested a range of glucose concentrations and found that total licks over daily 23-h sessions significantly decreased in GLX compared with Sham rats, but this difference failed to reach significance when intake or any bout parameter was measured. These results show that the signals in the GL normally contribute to processes involved with corn oil bout termination as opposed to bout initiation. GL-derived signals could potentially provide input to "reward" circuits in the ventral forebrain that could serve to maintain ingestion during a meal or, alternatively, could act at the level of the brain stem to attenuate the inhibitory potency of vagal signals, thus delaying the onset of satiation, or perhaps contribute to a cephalic phase reflex modulation of the gut. Parasympathetic efferents in the GL innervating the von Ebner's glands, which secrete lingual lipase, which is thought to break down corn oil into detectable ligands, could also be playing a role in driving corn oil intake. Whatever the mechanism, an intact GL is clearly necessary in maintaining normal intake of corn oil.

Leptin modulates the response to oleic acid in the pharynx.

Leptin released from the adipose tissues is known to inhibit obesity by regulating food intake. In this study, we investigated the effect of leptin on afferent nerve responses to fats and fatty acid in the pharyngolaryngeal region. The afferent nerve activities were recorded from the whole nerve bundle or pauci-fiber bundles of the pharyngeal branch of the glossopharyngeal nerve (GPN-ph) in Wistar normal and fatty rats. Oleic acid (long-chain fatty acid), mineral oil (nonfat oil) and safflower oil (vegetable oil; middle-chain fatty acid) were applied to the surface of pharyngolaryngeal mucous membrane. Oleic acid elicited vigorous stimulation of the GPN-ph activity in both normal and fatty rats but other oils had no significant effect on the activity. After intravenous administration of leptin (30 ng/kg, 1 ml), the response to oleic acid was significantly decreased in normal rats, whereas such a decrease was not found in fatty rats. These results are the first findings to indicate the existence of a suppressive mechanism of leptin on the response of the GPN-ph to fatty acid in normal rats, but that such a mechanism is lacking in fatty rats.

A Case of Taste Distortion and Phantogeusia after Tonsillectomy / 대한이비인후과학회지

Dysgeusia after tonsillectomy is a rare complication and there have been a few reports in the literature. The most possible cause of this complication is thought to be direct or indirect injury to the glossopharyngeal nerve or its lingual branch. Other suggested causes are lack of dietary zinc and habitual drug intake. We report a 51-year-old man, who presented severe parageusia and phantogeusia following tonsillectomy that was performed for chronic tonsillitis. The surgery was performed by electrocautery dissection without identifiable injury to the glossopharyngeal nerve. Dysgeusia developed 3 weeks after the operation and he complained loss of appetite and significant weight loss. He did not take any drug habitually that could affect his sense of taste. His serum zinc level (48 microgram/dl, normal range : 61-121 microgram/dl) was decreased. We prescribed a mineral supplement containing vitamin B complex and therapeutic dose of zinc. Eight months after the operation, his taste function was not recovered and he still retained problems related to diet. This case indicates that a patient should be informed of the risk of postoperative taste disturbance after tonsillectomy as being one of the rare complications.

Preventive strategies for aspiration pneumonia in elderly disabled persons.

Pneumonia is the fourth leading cause of death despite the availability of potent new antimicrobials in Japan. Aspiration of oropharyngeal bacterial pathogens to the lower respiratory tract is one of the most important risk factors for pneumonia. Impairments in swallowing and cough reflexes among disabled older persons, e.g., related to cerebrovascular disease, increase the risk of pneumonia. Thus, strategies to reduce the volumes and pathogenicity of aspirated material should be pursued. Since both swallowing and cough reflexes are mediated by endogenous substance P contained in the vagal and glossopharyngeal nerves, pharmacologic therapy using angiotensin-converting enzyme inhibitors, which decrease substance P catabolism, can improve both reflexes and result in the lowering of the risk of pneumonia. Similarly, since the production of substance P is regulated by dopaminergic neurons in the cerebral basal ganglia, treatment with dopamine analogs or potentiating drugs such as amantadine can reduce the incidence of pneumonia. Furthermore, since mortality from infections correlates with cutaneous anergy, interventions that reverse these age-associated changes in the immune system are also effective. The main theme of this review is to discuss how pneumonia develops in disabled older people and to suggest preventive strategies that may reduce the incidence of pneumonia among these subjects.

Hypothalamic histamine release by taste stimuli in freely moving rats: possible implication of palatability.

Our previous study indicated that taste information via the chorda tympani (CT) activates the central histaminergic system in anesthetized rats. However, the physiological roles of taste-induced histamine release remain unknown, thus to further investigate the relationship between histamine release and gustatory information, in the present study we investigated the effect of taste stimuli infused intraorally on histamine release using in vivo microdialysis in free moving rats. Consistent with findings from our previous study, application of NaCl and HCl caused significant increases in histamine levels further supporting the suggestion that this phenomenon is attributed to the excitation of the CT. When rats were intraorally infused with quinine HCl (QHCl) solution, a significant increase in hypothalamic histamine release was observed. On the other hand, histamine release was decreased by sucrose and saccharin solutions. When rats were conditioned to acquire taste aversion to sucrose solution or saccharin solution, instead of the histamine decrease seen by the palatable solutions, the pattern of histamine release was similar to that seen by QHCl solution. From these observations, it is concluded that the histamine release by the infusion of these tastants may be explained by two mechanisms-by causing a transient increase after taste stimulation and by causing a decrease relative to the tastant's palatability.

Modified infiltration technique in tonsillectomy: expanded case report of 25 children.

OBJECTIVE: To introduce a modified infiltration technique of anesthetic mixture in order to reduce post-tonsillectomy pain based on histo-anatomic observations and tonsil's innervation detection. DESIGN: Histo-anatomic, expanded case report. SETTING: Tertiary care facility in Beirut, Lebanon. PATIENTS: One hundred and seven patients who underwent tonsillectomy allocated in three groups. INTERVENTIONS: Histo-anatomic observations were studied in 62 patients (group I). Nerve-stimulator detection was performed in group II (20 children). An expanded case report of 25 children (group III) was conducted using a modified infiltration technique based on the findings of the histo-anatomic observations and nerve detection. OUTCOME MEASURES: Post-operative pain at 0, 6, 12h and once daily for the 10-day follow-up period, hemodynamic stability, hospital stay, patient satisfaction and analgesics consumption were assessed. RESULTS: The nerve-stimulator confirmed the histo-anatomic findings by strong contractions of the superior constrictor muscle, soft palate and uvula when the needle is mainly in the middle part of the peritonsillar area where the glossopharyngeal nerve branches predominate. No visual analogue scale median exceeded 1 for any child at any predetermined time interval, only three children (12%) required opoiods during the follow-up period. All children (100%) were discharged the same day, only 4% of parents were unsatisfied. Hemodynamic stability was maintained during pre- and post-operation. CONCLUSION: This modified technique with minimal volume of anesthetic mixture seems to reduce post-operative pain in tonsillectomy patients; a randomized double-blinded prospective study was designed based on the findings in this initial series of children.

Association between plasma zinc concentration and zinc kinetic parameters in premenopausal women.

The objective of this study was to measure relationships between plasma zinc (Zn) concentrations and Zn kinetic parameters and to measure relationships of Zn status with taste acuity, food frequency, and hair Zn in humans. The subjects were 33 premenopausal women not taking oral contraceptives and dietary supplements containing iron and Zn. Main outcomes were plasma Zn concentrations, Zn kinetic parameters based on the three-compartment mammillary model using 67Zn as a tracer, electrical taste detection thresholds, and food frequencies. Lower plasma Zn was significantly (P < 0.01) associated with smaller sizes of the central and the lesser peripheral Zn pools, faster disappearance of tracer from plasma, and higher transfer rate constants from the lesser peripheral pool to the central pool and from the central pool to the greater peripheral pool. The break points in the plasma Zn-Zn kinetics relationship were found between 9.94 and 11.5 micromol/l plasma Zn. Smaller size of the lesser peripheral pool was associated with lower frequency of beef consumption and higher frequency of bran breakfast cereal consumption. Hypozincemic women with plasma Zn <10.7 micromol/l or 700 ng/ml had decreased thresholds of electrical stimulation for gustatory nerves. Our results based on Zn kinetics support the conventional cutoff value of plasma Zn (10.7 micromol/l or 700 ng/ml) between normal and low Zn status.

Effects of glossopharyngeal nerve transection on central and peripheral cytokines and serum corticosterone induced by localized inflammation.

Bilateral transection of the glossopharyngeal nerves (GLOx) disrupts the immune-to-brain communication from the posterior oral cavity. The current report tested whether this effect is due to the afferent (sensory) or efferent (parasympathetic motor) components of the nerve. Injection of lipopolysaccharide (LPS) into the soft palate (ISP) of GLOx or sham-operated (SHAM) rats increased the circulating levels of interleukin-1beta (IL-1beta), interleukin-1 receptor antagonist (IL-1ra) and corticosterone (CORT), as well the hypothalamic content of IL-1beta; no difference in circulating levels and hypothalamic content was found between GLOx and SHAM at 2 and 4.5 h after LPS injection. These results indicate that glossopharyngeal neural efferents do not mediate the effects of GLOx on the immune-to-brain communication.

Effects of bicarbonate buffer on acetylcholine-, adenosine 5'triphosphate-, and cyanide-induced responses in the cat petrosal ganglion in vitro.

Acetylcholine (ACh), adenosine 5'-triphosphate (ATP) and sodium cyanide (NaCN) activate petrosal ganglion (PG) neurons in vitro, and evoke ventilatory reflexes in situ, which are abolished after bilateral chemosensory denervation. Because in our previous experiments we superfused the isolated PG with solutions free of CO2/HCO3- buffer, we studied its effects on the PG responses evoked in vitro. PGs from adult cats were superfused at a constant pH, with HEPES-supplemented (5 mM) saline with or without CO2/HCO3- (5%/26.2 mM) buffer, and carotid (sinus) nerve frequency discharge (fCN) recorded. Increases in fCN evoked by ACh, ATP and NaCN in CO2- free saline were significantly reduced (P < 0.05, Wilcoxon test) when CO2/HCO3- was present in the superfusion medium. Thus, the presence of CO2/HCO3- buffer appears to reduce PG neurons sensitivity to ACh, ATP and NaCN, an effect that may underlie the lack of ventilatory reflexes after bilateral chemodenervation.

Ninth cranial nerve stimulation for epilepsy control. Part 1: efficacy in an animal model.

OBJECTIVE: To characterize the effects of stimulation of the nerve of Hering (HN; cranial nerve nine) in controlling seizure activity using a canine model. METHODS: Using penicillin applied topically to a region of the cerebral cortex, 16 seizure-type continuous epileptiform discharges were generated. Ten specimens of HN (five left-sided and five right-sided) were dissected from the cervical region in five dogs and stimulated at varying parameters to determine the effects in controlling epileptiform activity. Electroencephalography (using a multielectrode array), electrocardiography and other vital signs were continuously monitored for side effects. RESULTS: Resolution of continuous epileptiform activity following stimulation was found in 12 of 16 trials (75%); no spontaneous resolution was noted in the absence of stimulation, and stimulation significantly shortened seizure duration (p < 0.05). Mean epileptiform activity duration was 139 s prior to stimulation (range 1-432 s), with a mean poststimulation delay of 17 s until resolution and a mean interictal time of 399 s. Two specimens became free of seizure activity for the duration of our study (p < 0.001). No significant side effects (such as the potentially life-threatening cardiac problems seen with right-sided cervical vagal nerve stimulation) were found with stimulation of either left- or right-sided HN. Stimulation of other regional nerves (e.g. twelfth cranial nerve, nerves of the cervical plexus) failed to yield similar control of epileptiform activity. CONCLUSIONS: The results of this pilot study suggest that stimulation of the HN can successfully control focal seizure activity in the majority of cases. Pending further study, stimulation of the HN may have a role in the management of patients suffering from medically and otherwise surgically refractory epilepsy.

Ninth cranial nerve stimulation for epilepsy control. Part 2: surgical feasibility in humans.

OBJECTIVE: To determine the anatomical and surgical feasibility of placement of a stimulator around the nerve of Hering (HN; a branch of cranial nerve nine). We previously determined the success of HN stimulation in controlling epileptiform activity in a canine model study. The present study assessed the ability to extrapolate the ease of surgical dissection and surrounding anatomy to humans. METHODS: Fifteen human cadavers (8 male, 7 female) were studied. The HN on each side was specifically evaluated in each specimen with respect to its presence, size, surgically accessible length below the mandibular angle, relationship to the internal carotid artery (ICA) and carotid bifurcation and relation to the common facial vein (CFV), thyroid cartilage (superior edge) and superior cervical ganglion (SCG). RESULTS: All 15 cadavers exhibited specimens of HN bilaterally, with the nerve diameter ranging from 0.5 to 1.5 mm (mean 1.0 mm); in relation to the ICA, the HN coursed anteromedially in 60%, anteriorly in 33% and anterolaterally in 7% of cases, and appeared to distinctly emerge at the level of the carotid bifurcation in all specimens. The surgically accessible length below the mandibular angle ranged from 6 to 30 mm (mean 15 mm). Relative to the carotid bifurcation, the superior edge of the thyroid cartilage was -35 to 33 mm (mean -5.4 mm) above; the CFV, which was clearly identifiable in only two thirds of the specimens, was -10 to 15 mm (mean 3.0 mm) above; and the inferiormost portion of the SCG was 6-30 mm (mean 16.6 mm) above. CONCLUSION: This study indicates that the HN was clearly present and surgically accessible in all human specimens. Based on the present study and our previous canine study, HN stimulation could be an important therapy for medically intractable epilepsy.

Effects of bicarbonate buffer on acetylcholine-, adenosine 5'triphosphate-, and cyanide-induced responses in the cat petrosal ganglion in vitro

Acetylcholine (ACh), adenosine 5'-triphosphate (ATP) and sodium cyanide (NaCN) activate petrosal ganglion (PG) neurons in vitro, and evoke ventilatory reflexes in situ, which are abolished after bilateral chemosensory denervation. Because in our previous experiments we superfused the isolated PG with solutions free of CO2 /HCO3¯ buffer, we studied its effects on the PG responses evoked in vitro. PGs from adult cats were superfused at a constant pH, with HEPES-supplemented (5 mM) saline with or without CO2 /HCO3¯ (5% / 26.2 mM) buffer, and carotid (sinus) nerve frequency discharge (âCN) recorded. Increases in âCN evoked by ACh, ATP and NaCN in CO2-free saline were significantly reduced (P<0.05, Wilcoxon test) when CO2 / HCO3¯ was present in the superfusion medium. Thus, the presence of CO2 / HCO3¯ buffer appears to reduce PG neurons sensitivity to ACh, ATP and NaCN, an effect that may underlie the lack of ventilatory reflexes after bilateral chemodenervation

Anesthesia of the chorda tympani nerve and taste phantoms.

The chorda tympani nerve innervates the anterior two-thirds and the glossopharyngeal nerve, the posterior one-third, of each side of the tongue. Previous work showed that anesthesia of one chorda tympani increased the perceived intensity of quinine applied to an area innervated by the contralateral glossopharyngeal nerve, but decreased the perceived intensity of NaCl applied to an area innervated by the ipsilateral glossopharyngeal nerve. The data presented here corroborate that earlier finding and show that if both chorda tympani nerves are anesthetized, the taste of quinine is intensified and the taste of NaCl diminished at areas innervated by the glossopharyngeal on both sides of the tongue. In about 40% of the subjects, tastes occurred in the absence of stimulation (we call these tastes phantoms). The phantoms were usually localized to the posterior tongue contralateral to the anesthesia and they were abolished when a topical anesthetic was applied to the area where they were perceived. Phantoms like these may be a source of clinical dysgeusia in patients with localized taste damage. The phantoms may result because the anesthesia releases inhibition normally occurring between the central projection areas of different taste nerves.

Effect of oral administration of Pinellia ternata, Zingiberis rhizoma and their mixture on the efferent activity of the gastric branch of the vagus nerve in the rat.

The effect of taste stimulation of Pinellia temata, Zingiberis rhizoma and their mixture on the efferent activity of the gastric branch of the vagus nerve was observed in the anesthetized rat. Taste stimulation by Pinellia ternata (50 mg/ml, 10 min) resulted in a suppression in vagal gastric nerve activity. On the contrary, stimulation by Zingiberis rhizoma (50 mg/ml, 10 min) caused a facilitation in efferent activity. The mixture of Pinellia ternata and Zingiberis rhizoma (5:1, 50 mg/ml, 10 min stimulation) demonstrated no suppressive effect on gastric nerve activity. These observations indicate that it is reasonable to prescribe Pinellia ternata with Zingiberis rhizoma in traditional Japanese medicine to prevent suppressive effect of the taste of Pinellia ternata on gastric function.