The Relationship between Extracellular and Intracellular Slow Waves

1984 ◽  
pp. 405-411
Author(s):  
N. G. Durdle ◽  
Y. J. Kingma ◽  
K. L. Bowes
Keyword(s):  
Slow Waves ◽  
The Relationship

Spinal Unit Activity During Synchronization of a Convulsive Type (Strychnine Tetanus)

1956 ◽  
Vol 186 (2) ◽  
pp. 263-270 ◽  
Author(s):  
Carlo A. Terzuolo ◽  
Bo E. Gernandt
Keyword(s):  
Spinal Cord ◽  
Intravenous Injection ◽  
Unit Activity ◽  
Single Unit ◽  
Slow Waves ◽  
Single Unit Activity ◽  
Oscillatory Potential ◽  
Convulsive Activity ◽  
Decerebrate Cat ◽  
The Relationship

Single unit activity during convulsive synchronized discharge and the relationship between unit activity and slow ‘waves’ were studied in the spinal cord of the decerebrate cat after intravenous injection of strychnine. Steel needle microelectrodes were used. Units did discharge in burst (from 1 to 5 impulses) only in coincidence with the slow oscillatory potential (tetanic ‘waves’). The firing is confined to the rising phase of this potential. Changes in d.c. state related to a convulsive activity were also studied. A relationship was found between frequency of the tetanic rhythm and d.c. state of spinal structures. The mechanisms of synchronization and rhythmicity of the convulsive activity in a population of neurons are discussed in connection with the problem of interaction between units.

The Relationship between Regular Sinusoidal Waves in the Tissue at Lung-related Acupuncture Points and the Respiration Pacesetter Mechanism

2019 ◽  
Author(s):  
Fletcher Kovich
Keyword(s):  
Real Time ◽  
Respiration Rate ◽  
Heart Beat ◽  
Slow Waves ◽  
The Other ◽  
Acupuncture Points ◽  
Post Exercise ◽  
The Real ◽  
The Relationship

Background: While investigating the real-time impedance at acupuncture points (acupoints), it was found that regular sinusoidal waves were present that corresponded to the pulsing of certain organs, such as respiration and duodenal waves, the stomach’s slow waves, and also the heart’s beating.Methods: This study investigated such respiration waves at lung-related acupoints to clarify their relation to the respiration pacesetter mechanism. The impedance at key acupoints was monitored in real time while the patients’ breathing slowed after exercise.Results: In all 7 patients studied, the respiration and heart-beat waves matched the rates in the corresponding organs at rest, and did not vary markedly due to exercise. In 3 of the 7 patients, their post-exercise respiration rate exactly matched that of their duodenal waves, but then dropped, stepwise, back to their usual respiration rate. In the other 4 patients, their post-exercise respiration rate did not reach that of their duodenal waves, so this pattern was not triggered.Conclusion: The results suggested that as well as the brainstem respiration pacesetter, there was also a separate “pace signal” present which remained constant and seemed to define the respiration rate when at rest. It is currently unknown what mechanism causes the respiration rate to increase due to exercise. But these results suggest that the brainstem pacesetter is sometimes guided by the duodenal pace signal instead of the lung pace signal, which may explain how the pacesetter is able to jump to a higher rate, even though its chemoreceptor inputs may be unchanged.

Similarities and differences in the propagation of slow waves and peristaltic waves

2002 ◽  
Vol 283 (3) ◽  
pp. G778-G786 ◽  
Author(s):  
Wim J. E. P. Lammers ◽  
Betty Stephen ◽  
John R. Slack
Keyword(s):  
Longitudinal Axis ◽  
Slow Waves ◽  
Wave Direction ◽  
Wave Fronts ◽  
Lower Velocity ◽  
Electrical Potentials ◽  
Similarities And Differences ◽  
Peristaltic Contractions ◽  
The Relationship

The relationship between slow waves and peristaltic reflexes has not been well analyzed. In this study, we have recorded the electrical activity of slow waves together with that generated by spontaneous peristaltic contractions at 240 extracellular sites simultaneously. Recordings were made from five isolated tubular and six sheet segments of feline duodenum superfused in vitro. In all preparations, slow waves propagated as broad wave fronts along the longitudinal axis of the preparation in either the aborad or the orad direction. Electrical potentials recorded during peristalsis (peristaltic waves) also propagated as broad wave fronts in either directions. Peristaltic waves often spontaneously stopped conducting (46%), in contrast to slow waves that never did. Peristaltic waves propagated at a lower velocity than the slow waves (0.98 ± 0.25 and 1.29 ± 0.28 cm/s, respectively; P < 0.001; n = 24) and in a direction independent of the preceding slow wave direction (64% in the same direction, 46% in the opposite direction). In conclusion, slow waves and peristaltic waves in the isolated feline duodenum seem to constitute two separate electrical events that may drive two different mechanisms of contraction in the small intestine.

The Relationship between Slow and Sharp Waves (Spikes) and Also Clinical Seizures

2002 ◽  
Vol 33 (4) ◽  
pp. 165-170 ◽  
Author(s):  
John R. Hughes ◽  
C. C. Wang
Keyword(s):  
Mental Status ◽  
Slow Wave ◽  
First Record ◽  
Slow Waves ◽  
Status Change ◽  
Mental Status Change ◽  
Sharp Waves ◽  
Number Of Patients ◽  
Number Of Discharges ◽  
The Relationship

This study investigated the relationship between slow waves and sharp waves (spikes) and also clinical seizures in 255 patients with 694 EEGs over a 25-yr period. Slow waves were quantified into five groups, sharp waves into three groups and clinical seizures also into three groups. In general, as clinical seizures increased, the number of patients with many discharges increased and the number with only rare discharges decreased. Also, as patients became seizure free, there was a decreasing incidence of many sharp waves and an increasing incidence of only rare sharp waves. No relationships could be found in patients with a typical number of discharges or a steady number of seizures. Thus, a relationship between sharp waves and seizures was found mainly when there were changes in these variables. For sharp and slow waves, rare discharges were most often associated with mild slowing, while many discharges were most often related to a marked degree of slow wave abnormality. The combination of slow and sharp waves together, compared with only one type of EEG abnormality, was associated with more clinical neurological symptoms, especially a mental status change. The EEG groups were divided into four types of findings of slow and sharp waves, appearing in at least a first and/or second record. The results from these four EEG groups allow for a prediction of the findings to be found in a second record, based on the results of the first EEG. In general, there was a relationship between more slow waves, more sharp waves and more seizures. Also minimal slowing and rare discharges on the first record tended to disappear in the next EEG.

scholarly journals Validation of non-invasive body-surface gastric mapping for detecting electrophysiological biomarkers by simultaneous high-resolution serosal mapping in a porcine model

2021 ◽  
Author(s):  
Stefan Calder ◽  
Leo K Cheng ◽  
Christopher Andrews ◽  
Niranchan Paskaranandavadivel ◽  
Stephen Waite ◽  
...  
Keyword(s):  
High Resolution ◽  
Slow Wave ◽  
Body Surface ◽  
Porcine Model ◽  
Slow Waves ◽  
Electrode Spacing ◽  
Non Invasive ◽  
Gastric Slow Waves ◽  
The Relationship ◽  
Gastric Mapping

Gastric disorders are increasingly prevalent, but reliable clinical tools to objectively assess gastric function are lacking. Body-surface gastric mapping (BSGM) is a non-invasive method for the detection of gastric electrophysiological biomarkers including slow wave direction, which have correlated with symptoms in patients with gastroparesis and functional dyspepsia. However, no studies have validated the relationship between gastric slow waves and body surface activation profiles. This study aimed to comprehensively evaluate the relationship between gastric slow waves and body-surface recordings. High-resolution electrode arrays were placed to simultaneously capture slow waves from the gastric serosa (32 x 6 electrodes at 4 mm resolution) and abdominal surface (8x8 at 20 mm inter-electrode spacing) in a porcine model. BSGM signals were extracted based on a combination of wavelet and phase information analyses. A total of 1185 individual cycles of slow waves assessed, out of which 897 (76%) were normal antegrade waves, occurring in 10/14 (71%) subjects studied. BSGM accurately detected the underlying slow wave in terms of frequency (r = 0.99, p = 0.43) as well as the direction of propagation (p = 0.41, F-measure: 0.92). In addition, the cycle-by-cycle match between BSGM and transitions of gastric slow waves in terms either or both temporal and spatial abnormalities was demonstrated. These results validate BSGM as a suitable method for non-invasively and accurately detecting gastric slow wave activation profiles from the body surface.

Participation of Ca currents in colonic electrical activity

1989 ◽  
Vol 257 (3) ◽  
pp. C451-C460 ◽  
Author(s):  
P. D. Langton ◽  
E. P. Burke ◽  
K. M. Sanders
Keyword(s):  
Slow Waves ◽  
Ca Current ◽  
Patch Clamp Technique ◽  
Inward Current ◽  
Whole Cell Patch Clamp ◽  
Mechanical Threshold ◽  
Inward Currents ◽  
Window Current ◽  
The Relationship ◽  
Ca Currents

Canine colonic myocytes were studied with the whole cell patch-clamp technique. In 1.8 mM Ca2+, inward currents were evoked by depolarization. Currents activated positive to -50 mV, peaked at approximately 0 mV, and reversed at approximately +50 mV. Inward current was potentiated by high external Ca2+ concentration and BAY K8644 and was decreased by low external Ca2+, nifedipine, and Mn2+, indicating that the current was carried by Ca2+. Overlap of the activation-inactivation properties indicated a "window current" range (-40 to -20 mV) in which inward current might be sustained for long durations at potentials achieved during electrical slow waves. Voltage-clamp protocols simulating physiological depolarizations elicited sustained inward currents. Maximum changes in intracellular Ca2+ resulting from sustained inward currents were calculated, which suggested that depolarizations at the level of slow waves may increase cell Ca2+ sufficiently to cause contraction. The data suggest that electrical slow waves in colonic myocytes are due in part to inward Ca current. This current appears to be sufficient to explain the relationship between slow waves and contractions and provides an explanation for the mechanical threshold in colonic muscles.

scholarly journals The Relationship between Regular Sinusoidal Waves in the Tissue at Lung-related Acupuncture Points and the Respiration Pacesetter Mechanism

2019 ◽  
Author(s):  
Fletcher Kovich
Keyword(s):  
Real Time ◽  
Respiration Rate ◽  
Heart Beat ◽  
Slow Waves ◽  
The Other ◽  
Acupuncture Points ◽  
Post Exercise ◽  
The Real ◽  
The Relationship

Background: While investigating the real-time impedance at acupuncture points (acupoints), it was found that regular sinusoidal waves were present that corresponded to the pulsing of certain organs, such as respiration and duodenal waves, the stomach&rsquo;s slow waves, and also the heart&rsquo;s beating.Methods: This study investigated such respiration waves at lung-related acupoints to clarify their relation to the respiration pacesetter mechanism. The impedance at key acupoints was monitored in real time while the patients&rsquo; breathing slowed after exercise.Results: In all 7 patients studied, the respiration and heart-beat waves matched the rates in the corresponding organs at rest, and did not vary markedly due to exercise. In 3 of the 7 patients, their post-exercise respiration rate exactly matched that of their duodenal waves, but then dropped, stepwise, back to their usual respiration rate. In the other 4 patients, their post-exercise respiration rate did not reach that of their duodenal waves, so this pattern was not triggered.Conclusion: The results suggested that as well as the brainstem respiration pacesetter, there was also a separate &ldquo;pace signal&rdquo; present which remained constant and seemed to define the respiration rate when at rest. It is currently unknown what mechanism causes the respiration rate to increase due to exercise. But these results suggest that the brainstem pacesetter is sometimes guided by the duodenal pace signal instead of the lung pace signal, which may explain how the pacesetter is able to jump to a higher rate, even though its chemoreceptor inputs may be unchanged.

Excitation-contraction coupling without Ca2+ action potentials in small intestine

1983 ◽  
Vol 244 (5) ◽  
pp. C356-C361 ◽  
Author(s):  
K. M. Sanders
Keyword(s):  
Small Intestine ◽  
Slow Wave ◽  
Action Potentials ◽  
Wave Amplitude ◽  
Channel Blocker ◽  
Slow Waves ◽  
Contractile Apparatus ◽  
Contraction Coupling ◽  
Wave Cycle ◽  
The Relationship

Sensitive mechanical and intracellular electrical recordings showed that phasic contractions occurred in response to electrical slow waves in the absence of Ca2+ action potentials. Drugs that either enhanced or depressed slow waves were used to study the relationship between slow-wave amplitude and the amplitude of the phasic contractions. Acetylcholine (Ach) (10(-8) to 3 X 10(-7) M) increased slow waves and contractions without causing action potentials. When ACh was raised to 10(-6) M, action potentials were elicited and accompanying contractions increased in amplitude by at least a factor of five. The Ca2+ channel blocker, Mn2+ (0.5 mM), decreased slow-wave amplitude and the associated phasic contractions. These data agree with a previous study (12), suggesting that an oscillation in intracellular Ca2+ occurs during each slow-wave cycle. The present study suggests that the increase in intracellular Ca2+ during the slow wave is sufficient to activate the contractile apparatus.

Interstellar gas in the central region of the Galaxy

1967 ◽  
Vol 31 ◽  
pp. 239-251 ◽  
Author(s):  
F. J. Kerr
Keyword(s):  
Central Region ◽  
Galactic Plane ◽  
Neutral Hydrogen ◽  
Continuum Emission ◽  
Galactic Centre ◽  
Interstellar Gas ◽  
Hydrogen Recombination ◽  
The Galaxy ◽  
Centre Region ◽  
The Relationship

A review is given of information on the galactic-centre region obtained from recent observations of the 21-cm line from neutral hydrogen, the 18-cm group of OH lines, a hydrogen recombination line at 6 cm wavelength, and the continuum emission from ionized hydrogen.Both inward and outward motions are important in this region, in addition to rotation. Several types of observation indicate the presence of material in features inclined to the galactic plane. The relationship between the H and OH concentrations is not yet clear, but a rough picture of the central region can be proposed.

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