Bulbar gustatory responses to anterior and to posterior tongue stimulation in the rat

1965 ◽  
Vol 209 (1) ◽  
pp. 105-110 ◽  
Author(s):  
Bruce P. Halpern ◽  
Linda M. Nelson
Keyword(s):  
Active Zone ◽  
The Other ◽  
Anterior Region ◽  
Reference Standard ◽  
Neural Responses ◽  
Quinine Hydrochloride ◽  
Posterior Tongue ◽  
Stimulation Of

Amplitudes of neural responses in the nucleus of the fasciculus solitarius to stimulation of the tongue with quinine hydrochloride were analyzed using the response to NaCl as a reference standard. Three distinguishable areas were observed within the gustatory response zone of the nucleus. One area, responsive only to stimulation of the anterior region of the tongue, was at the anterolateral limit of the active zone. A second area, caudal and medial to the first, responded to both anterior and posterior tongue-region stimulation, the latter region yielding larger responses. Medial to both of the other areas was a third, highly responsive area, which responded only to posterior tongue-region stimulation.

Repeated sodium depletion affects gustatory neural responses in the nucleus of the solitary tract of rats

1997 ◽  
Vol 273 (4) ◽  
pp. R1381-R1391 ◽  
Author(s):  
Ryoi Tamura ◽  
Ralph Norgren
Keyword(s):  
The Other ◽  
Dietary Sodium ◽  
Gustatory System ◽  
Solitary Tract ◽  
Sodium Restriction ◽  
Neural Responses ◽  
Sodium Depletion ◽  
Sodium Appetite ◽  
The Third ◽  
Quinine Hydrochloride

Furosemide sodium depletions were induced repeatedly to determine the effects on gustatory neural responses in the nucleus of the solitary tract (NST) of chronically prepared, but lightly anesthetized, rats. Sodium-replete and sodium-deplete conditions were alternated four times in each rat. When rats were under depleted conditions, the responses to NaCl were significantly greater than in sodium-replete conditions. This effect was attributable primarily to an increase in the magnitude of response of those neurons that responded better to NaCl than to the other standard stimuli (sucrose, citric acid, and quinine hydrochloride). In addition, the largest change in responsiveness of the NaCl-best neurons occurred during the third and fourth sodium depletions. These results are essentially opposite to those reported for NST neurons when sodium appetite is induced by dietary sodium restriction. This suggests that the coding of intensity in the gustatory system is dependent not only on the animal’s deprivation condition, but also the method through which the deprivation is produced.

EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar
Keyword(s):  
Protein Synthesis ◽  
Actinomycin D ◽  
The Other ◽  
Leucine Incorporation ◽  
Short Term ◽  
Other Hand ◽  
Thyroid Glands ◽  
Translational Level ◽  
Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

scholarly journals Receptor-operated Ca2+ channels in gastric parietal cells: gastrin and carbachol induce Ca2+ influx in depleting intracellular Ca2+ stores

1993 ◽  
Vol 289 (1) ◽  
pp. 117-124 ◽  
Author(s):  
S Roche ◽  
J P Bali ◽  
R Magous
Keyword(s):  
Steady State ◽  
Receptor Activation ◽  
Parietal Cells ◽  
The Other ◽  
Bivalent Cation ◽  
Gtp Binding ◽  
Gastric Parietal Cells ◽  
Type Receptor ◽  
Ca2 Channels ◽  
Stimulation Of

The mechanism whereby gastrin-type receptor and muscarinic M3-type receptor regulate free intracellular Ca2+ concentration ([Ca2+]i) was studied in rabbit gastric parietal cells stimulated by either gastrin or carbachol. Both agonists induced a biphasic [Ca2+]i response: a transient [Ca2+]i rise, followed by a sustained steady state depending on extracellular Ca2+. Gastrin and carbachol also caused a rapid and transient increase in Mn2+ influx (a tracer for bivalent-cation entry). Pre-stimulation of cells with one agonist drastically decreased both [Ca2+]i increase and Mn2+ influx induced by the other. Neither diltiazem nor pertussistoxin treatment had any effect on agonist-stimulated Mn2+ entry. Thapsigargin, a Ca(2+)-pump inhibitor, induced a biphasic [Ca2+]i increase, and enhanced the rate of Mn2+ entry. Preincubation of cells with thapsigargin inhibits the [Ca2+]i increase as well as Mn2+ entry stimulated by gastrin or by carbachol. Thapsigargin induced a weak but significant increase in Ins(1,4,5)P3 content, but this agent had no effect on the agonist-evoked Ins(1,4,5)P3 response. In permeabilized parietal cells, Ins(1,4,5)P3 and caffeine caused an immediate Ca2+ release from intracellular pools, followed by a reloading of Ca2+ pools which can be prevented in the presence of thapsigargin. We conclude that (i) gastrin and carbachol mobilize common Ca2+ intracellular stores, (ii) Ca2+ permeability secondary to receptor activation involves neither a voltage-sensitive Ca2+ channel nor a GTP-binding protein from the G1 family, and (iii) agonists regulate common Ca2+ channels in depleting intracellular Ca2+ stores.

Assessing bias, precision, and agreement in method comparison studies

2019 ◽  
Vol 29 (3) ◽  
pp. 778-796 ◽  
Author(s):  
Patrick Taffé
Keyword(s):  
Measurement Method ◽  
Method Comparison ◽  
Estimation Procedure ◽  
Measurement Methods ◽  
Repeated Measurements ◽  
Confidence Bands ◽  
The Other ◽  
Reference Standard ◽  
Simultaneous Confidence Bands ◽  
Index Of Agreement

Recently, a new estimation procedure has been developed to assess bias and precision of a new measurement method, relative to a reference standard. However, the author did not develop confidence bands around the bias and standard deviation curves. Therefore, the goal in this paper is to extend this methodology in several important directions. First, by developing simultaneous confidence bands for the various parameters estimated to allow formal comparisons between different measurement methods. Second, by proposing a new index of agreement. Third, by providing a series of new graphs to help the investigator to assess bias, precision, and agreement between the two measurement methods. The methodology requires repeated measurements on each individual for at least one of the two measurement methods. It works very well to estimate the differential and proportional biases, even with as few as two to three measurements by one of the two methods and only one by the other. The repeated measurements need not come from the reference standard but from either measurement methods. This is a great advantage as it may sometimes be more feasible to gather repeated measurements with the new measurement method.

On Research and Other Matters

1922 ◽  
Vol 26 (140) ◽  
pp. 325-330
Author(s):  
S. Heckstall Smith
Keyword(s):  
British Empire ◽  
Air Force ◽  
The Other ◽  
Other Hand ◽  
Secretary Of State ◽  
The Press ◽  
The Subject ◽  
Stimulation Of

If the thought of another war troubles you, then don't read this article. If you would rather say to yourself as the Secretary of State said to the Air Conference, “ There won't be another war for ten years, so why worry? ” then no doubt you will think with him that it is better to let other nations have alk the bother and expense of trying to advance; after all, we are jolly fine fellows and can soon pick up. If, on the other hand, you have imagination which gives you a nasty queasy sensation when you think of what might be, then perhaps the following notes, albeit disjointed and mostly stale, may at least conjure up in you thoughts of your own on the subject. This is all that is needed to help, our advancement in the air–the stimulation of spoken and written thoughts by the British nation, for if every taxpayer in the British Empire says “ Air Force,” then the Press and Parliament will say it too.

scholarly journals Interferential comparison of the red and other radiations emitted by a new cadmium lamp and the michelson lamp

1933 ◽  
Vol 139 (837) ◽  
pp. 202-218 ◽  
Keyword(s):  
Fine Structure ◽  
High Temperature ◽  
Wave Length ◽  
The Other ◽  
Reference Standard ◽  
Definite Evidence ◽  
Electro Magnetic ◽  
The Many ◽  
Red Radiation ◽  
Red Line

It is now generally recognised that future definitions of the units of length will probably be based on the length of a wave of visible light. At present the wave-length of the red radiation of cadmium serves as the basis of all measurements of the lengths of electro-magnetic waves which are perceptible by optical means, and provisional sanction has been given to measurements of length on the same basis, as an alternative to direct reference to the metre. Whether the cadmium red radiation provides the best reference standard for all measurements of length has not yet been definitely established. Two international committees, one representing spectroscopists and the other metrologists, have sanctioned standard specifications for cadmium lamps of the Michelson type from which the red radiation may be produced. The two specifications differ from one another in certain details, but both are subject to the same objections. These objections are directed partly against the high temperature at which it is necessary to run the lamp and partly against the high voltage required to excite the radiation. Therefore, such hyperfine structure and asymmetry as may be present in the red line of cadmium is likely to be masked in the Michelson lamp by a combination of two phenomena —the enhanced Doppler effect due to the high temperature of the radiating cadmium atoms, and the effect of the moderately high intensity of the electric field. Were this not so, it might be somewhat surprising that no definite evidence of fine structure or asymmetry had so far been observed in the red line from the Michelson lamp, notwithstanding the many careful examinations, with the aid of the most sensitive interferometers, to which this line has been subjected, in view of its importance as the reference standard for all other wave-lengths. Recently Nagaoka and Sugiura have recorded that they have observed slight evidences of structure in the red radiation when excited under special conditions in which great precautions were taken to ensure extreme sharpness of the line. It is believed, however, that no subsequent confirmation of this effect has yet been published.

Localization of Stereotactic Targets by Microrecording of Thalamic Somatosensory Evoked Potentials

Neurosurgery ◽  
1991 ◽  
Vol 28 (2) ◽  
pp. 223-230 ◽  
Author(s):  
Fumio Shima ◽  
Takato Morioka ◽  
Shozo Tobimatsu ◽  
Omiros Kavaklis ◽  
Motohiro Kato ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Median Nerve ◽  
Somatosensory Evoked Potentials ◽  
Practical Method ◽  
The Other ◽  
Basal Region ◽  
Thalamic Nuclei ◽  
Median Nerve Stimulation ◽  
Lower Amplitude ◽  
Stimulation Of

Abstract To improve the localization of stereotactic targets, somatosensory evoked potentials (SEPs) were recorded from the thalamus and subthalamic area using a specially designed semimicroelectrode in 61 patients and a conventional “macroclectrode” in 17 patients. By means of the semimicroelectrode, median nerve stimulation evoked two distinct SEPs, consisting of a diphasic wave with a huge positivity restricted to the nucleus ventrocaudalis (Vc) and a triphasic wave of lower amplitude with a major negativity in the ventral part of the nucleus ventrointermedius (Vim) and nucleus ventrooralis posterior (Vop) as well as the subthalamic lemniscal pathway. The Vim-Vc junction could thus be clearly delineated by an abrupt transition of SEPs from one type to the other with a precision of 1 mm. The parvicellular part of the Vc (Vcpc). situated in its basal region, was distinguishable from the Vc proper by a significant reduction of the positivity elicited by stimulation of the median nerve and by a rapid growth of a diphasic SEPs to stimulation of the posterior tibial nerve. In the other thalamic nuclei, stimulation of the median nerve elicited triphasic SEPs of a very small amplitude, suggesting a volume conduction current from the lemniscal pathway. With the macroclectrode, the positivity in the Vc was sensitive to electrode manipulation and the thalamic nuclei could not be distinctly outlined. SEP monitoring using the semimicroelectrode significantly improved the precision of target localization, which allowed minimizing of the volume of the therapeutic lesion without losing surgical effectiveness, while avoiding complications associated with increased penetration of the coagulating electrode. It is suggested that recording serial thalamic SEPs with the semimicroelectrode is a practical method to refine stereotactic targets in the thalamus.

scholarly journals The interaction between two trains of impulses converging on the same motoneurone

1929 ◽  
Vol 105 (738) ◽  
pp. 363-371 ◽  
Keyword(s):  
Mechanical Effect ◽  
The Other ◽  
Muscle Fibres ◽  
Flexor Muscle ◽  
Afferent Pathways ◽  
Afferent Nerves ◽  
Maximal Stimulation ◽  
The Common ◽  
The Relationship ◽  
Stimulation Of

It was shown in an earlier paper (7) that if maximal stimulation of either of two different afferent nerves can reflexly excite fractions of a given flexor muscle, there are generally, within the aggregate of neurones which innervate that muscle, motoneurones which can be caused to discharge by either afferent (i. e., motoneurones common to both fractions). The relationship which two such afferents bear to a common motoneurone was shown, by the isometric method of recording contraction, to be such that the activation of one afferent, at a speed sufficient to cause a maximal motor tetanus when trans­mitted to the muscle fibres, caused exclusion of any added mechanical effect when the other afferent was excited concurrently. This default in mechanical effect was called “occlusion.” Occlusion may conceivably be due to total exclusion of the effect of one afferent pathway on the common motoneurone by the activity of the other; but facilitation of the effect of one path by the activation of the other when the stimuli were minimal suggests that, in some circumstances at least, the effect of each could augment and summate with th at of the other at the place of convergence of two afferent pathways. Further investigation, using the action currents of the muscle as indication of the nerve impulses discharged by the motoneurone units, has now given some information regarding the effect of impulses arriving at the locus of convergence by one afferent path when the unit common to both is already discharging in response to impulses arriving by the other afferent path. Our method has been to excite both afferent nerves in overlapping sequence by series of break shocks at a rapid rate and to examine the action currents of the resulting reflex for evidence of the appearance of the rhythm of the second series in the discharge caused by the first when the two series are both reaching the motoneurone.

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