Control of Ciliary Activities by Adenosinetriphosphate and Divalent Cations in Triton-Extracted Models of Paramecium Caudatum

1973 ◽  
Vol 58 (3) ◽  
pp. 657-676 ◽  
Author(s):  
YUTAKA NAITOH ◽  
HIROKI KANEKO
Keyword(s):  
Cell Membrane ◽  
Divalent Cations ◽  
Power Stroke ◽  
Ciliary Activity ◽  
Paramecium Caudatum ◽  
Cell Models ◽  
Effective Power ◽  
Ciliary Beating ◽  
Triton X ◽  
Beating Frequency

1. Cilia of Paramecium candatum extracted with Triton X-100 were reactivated in the presence of ATP and Mg2+. 2. The beating frequency of the reactivated cilia is a function of both the ATP and Mg2+ concentrations. 3. The reactivated cell models swam forward when the Ca2+ concentrations in the ATP-Mg2+ medium was kept below 10-7M. They swam backward when the Ca2+ concentration was above 10-6M. This was due to a reversed orientation of the effective power stroke of the reactivated cilia. 4. In the absence of Mg2+ the cilia failed to beat, even though ATP was present. If Ca2+ was then added the cilia assumed a new orientation, pointing toward the anterior without beating. 5. Ni2+ inhibited ciliary beating in the reactivated models, but has no influence on changes in the orientation of the cilia produced by ATP and Ca2+. This suggests that one ATP-activated system is responsible for beating, while another governs the direction of the effective stroke. 6. Mn2+ is half as effective as Mg2+ for inducing ciliary beating in the extracted models in the presence of ATP. 7. Salyrgan strongly inhibits Mg2+-ATP activated ciliary activity of the model. 8. Bioelectric control of ciliary activity by the cell membrane of live animals is discussed.

scholarly journals Control of the Orientation of Cilia by ATP and Divalent Cations in Triton-Glycerol-Extracted Paramecium Caudatum

1986 ◽  
Vol 120 (1) ◽  
pp. 105-117 ◽  
Author(s):  
MUNENORI NOGUCHI ◽  
HIROSHI INOUÉ ◽  
KAZUMI KUBO
Keyword(s):  
Mode Of Action ◽  
Divalent Cations ◽  
The Other ◽  
Paramecium Caudatum ◽  
External Application ◽  
Ciliary Beating ◽  
Dependent Component ◽  
Triton X ◽  
Final Orientation

The ciliary responses of Paramecium caudatum, extracted in Triton X-100 andglycerol, to the external application of ATP and various divalent cations wereexamined. Ciliary beating could not be reactivated, but changes in the pointing direction of the cilia (the reorientation response) could be reactivated. The free Ca2+ concentration determined the final orientation of the cilia, which was towards the front when the Ca2+ concentration was above 10−6 moll−1, and towards the rear when below 10−7 moll−1. The reorientation response was inhibited by vanadate. These results indicate that the mechanism for the reorientation response is separable into two components. One is the movement of cilia to change their pointing direction, which, like normal ciliary beating, is energized by Mg-ATP2-. The other is the determination of the final pointing direction of the cilia, which is Ca2+ -dependent. Divalent cations can be classified into two groups according to their mode of action on the Ca2+ -dependent component. Sr2+ is an agonist and Ba2+, Zn2+ and Co2+ are antagonists to Ca2+ for the component.

Effect of pH, Viscosity and Ionic-Strength Changes on Ciliary Beating Frequency of Human Bronchial Explants

1983 ◽  
Vol 64 (4) ◽  
pp. 449-451 ◽  
Author(s):  
Chun Ka Luk ◽  
Mauricio J. Dulfano
Keyword(s):  
Ionic Strength ◽  
Marked Reduction ◽  
Beat Frequency ◽  
Ciliary Beat Frequency ◽  
Ciliary Activity ◽  
Rapid Loss ◽  
Significant Drop ◽  
Ciliary Beating ◽  
Beating Frequency

1. Ciliary activity is significantly influenced by chemical and physical properties of the liquid medium in which the cilia beat. 2. We studied the effect of changes in pH, ionic strength and viscosity on the ciliary beat frequency (CBF) of explants of human respiratory mucosa. 3. Optimal CBF was elicited at pH 7.0-9.0, with a marked reduction of CBF outside these limits. The CBF was well preserved at NaCl concentrations between 5 g/l (80 mmol/l) and 12 g/l (200 mmol/l), but there was rapid loss at concentrations below 0.5 gA (10 mmol/l). The cilia beat best at viscosities below 1.0 centipoises (1 mN s m−2). Increase of the viscosity gradually decreases CBF with a significant drop at viscosities above 87 millipoises. 4. It is concluded that the above limits may fairly accurately indicate the actual physical characteristics of the periciliary environment (‘sol layer’) in vivo.

Membrane Control of Ciliary Activity in the Protozoan Euplotes

1973 ◽  
Vol 58 (2) ◽  
pp. 437-462
Author(s):  
MILES EPSTEIN ◽  
ROGER ECKERT
Keyword(s):  
Membrane Potential ◽  
Normal Direction ◽  
Direct Access ◽  
Ciliary Activity ◽  
Cell Interior ◽  
Ciliary Beating ◽  
Ciliary Reversal ◽  
Intracellular Ca ◽  
Triton X ◽  
External Calcium

1. Membrane control of ciliary activity in the protozoan Euplotes was investigated by a combination of electrophysiological and cinematographic techniques. 2. The anal cirri, which are quiescent in the absence of stimulation, were selected for this study. 3. Membrane depolarization by means of injected current produced a reversal of the direction of beating (i.e. towards the cell anterior so as to make the ciliate swim backwards). Depolarization also increased the frequency of beating. Increasing depolarizations resulted in an increased number of reversed beats and increased frequency. 4. When the membrane potential was shifted beyond +70 mV, reversed beating did not occur until after the current pulse ended. 5. Depolarization did not evoke reversed beating when the external calcium (Ca) concentration was reduced to 10-6 M with EGTA. 6. Hyperpolarization caused the cirri to beat in a normal direction (i.e. towards the rear of the ciliate so as to cause the animal to swim forward). Increasing hyperpolarizations resulted in an increased number of forward beats and an increased frequency. 7. The cell was treated with the detergent Triton X-100 to permit Ca, Mg and ATP direct access through the extracted membrane to the cell interior. At Ca concentrations below 10-7 M, Mg-ATP-reactivated cilia of Triton-extracted cells beat normally. At Ca concentrations above approximately 10-7 M the reactivated beat resembled the reversed beat in the living cell. 8. The evidence suggests that membrane-regulated concentrations of intracellular Ca control the direction of ciliary beating. Thus, stimuli which produce an adequate Ca influx lead to ciliary reversal.

Differential effects of UTP, ATP, and adenosine on ciliary activity of human nasal epithelial cells

2001 ◽  
Vol 280 (6) ◽  
pp. C1485-C1497 ◽  
Author(s):  
Diane M. Morse ◽  
Jennifer L. Smullen ◽  
C. William Davis
Keyword(s):  
Epithelial Cells ◽  
Beat Frequency ◽  
Ciliary Beat Frequency ◽  
Ciliary Activity ◽  
Maximal Effect ◽  
Ciliary Beating ◽  
Mediated Effects ◽  
Human Nasal Epithelium ◽  
Human Nasal Epithelial Cells ◽  
Sustained Responses

The purinergic regulation of ciliary activity was studied using small, continuously superfused explants of human nasal epithelium. The P2Y2 purinoceptor (P2Y2-R) was identified as the major purinoceptor regulating ciliary beat frequency (CBF); UTP (EC50 = 4.7 μM), ATP, and adenosine-5′- O-(3-thiotriphosphate) elicited similar maximal responses, approximately twofold over baseline. ATP, however, elicited a post-peak sustained plateau in CBF (1.83 ± 0.1-fold), whereas the post-peak CBF response to UTP declined over 15 min to a low-level plateau (1.36 ± 0.16-fold). UDP also stimulated ciliary beating, probably via P2Y6-R, with a maximal effect approximately one-half that elicited by P2Y2-R stimulation. Not indicated were P2Y1-R-, P2Y4-R-, or P2Y11-R-mediated effects. A2B-receptor agonists elicited sustained responses in CBF approximately equal to those from UTP/ATP [5′-( N-ethylcarboxamido)adenosine, EC50 = 0.09 μM; adenosine, EC50 = 0.7 μM]. Surprisingly, ADP elicited a sustained stimulation in CBF. The ADP effect and the post-peak sustained portion of the ATP response in CBF were inhibited by the A2-R antagonist 8-( p-sulfophenyl)theophylline. Hence, ATP affects ciliary activity through P2Y2-R and, after an apparent ectohydrolysis to adenosine, through A2BAR.

Spectral characterization of ciliary beating: variations of frequency with time

1985 ◽  
Vol 249 (1) ◽  
pp. C160-C165 ◽  
Author(s):  
D. Eshel ◽  
Y. Grossman ◽  
Z. Priel
Keyword(s):  
Mathematical Model ◽  
Power Spectra ◽  
Ciliary Beating ◽  
Isolated Lung ◽  
Ciliary Cell ◽  
The Mathematical Model ◽  
Beating Frequency ◽  
Over Time ◽  
Dominant Frequencies

Ciliary beating frequency in tissue culture from frog palate and isolated lung was optically examined using instrumentation that was adjusted to measure a fraction of the surface area of a single ciliary cell. Consecutive 1-s segments of the analogue signal were fast Fourier transformed (FFT) to obtain a power spectrum. At room temperature, these power spectra changed over time from 1 s to the next. Each spectrum contained several dominant frequencies of similar intensities. Cooling the preparation resulted in a single-peak spectrum that was constant over time. A mathematical model is proposed to simulate these findings. The results and the mathematical model support the hypothesis that ciliary beating frequency fluctuates over short periods of time.

scholarly journals The human platelet membrane glycoprotein complex GP IIb-IIIa expresses antigenic sites not exposed on the dissociated glycoproteins

Blood ◽  
1984 ◽  
Vol 64 (6) ◽  
pp. 1246-1253
Author(s):  
JP Rosa ◽  
N Kieffer ◽  
D Didry ◽  
D Pidard ◽  
TJ Kunicki ◽  
...  
Keyword(s):  
Human Platelet ◽  
Divalent Cations ◽  
Platelet Membrane ◽  
Membrane Glycoproteins ◽  
Glycoprotein Complex ◽  
Weak Binding ◽  
The Individual ◽  
Triton X ◽  
Murine Monoclonal Antibodies ◽  
Partial Release

A number of recent reports have described murine monoclonal antibodies that react specifically with the complex formed by human platelet membrane glycoproteins (GP) IIb and IIIa. We show that the IgG L, a previously described human alloantibody isolated from a polytransfused thrombasthenia patient, has similar properties. When used in non- precipitating amounts in crossed immunoelectrophoresis (CIE), 125I-IgG L bound strongly to the IIb-IIIa complex. However, after dissociation of the complex with EDTA, only a weak binding to GP IIb and no binding to GP IIIa was detected. In further studies, increased amounts of IgG L were interacted with 125I-labeled membrane glycoproteins in (a) CIE and (b) classical indirect immunoprecipitation experiments. Although the antibody was able to quantitatively precipitate the IIb-IIIa complex from Triton X-100-soluble extracts of platelet membranes, no precipitation of GP IIb or GP IIIa was observed after divalent cation chelation. Addition of EDTA to immunoprecipitates containing GP IIb- IIIa resulted in dissociation and partial release of both glycoproteins. The interaction of the IgG L with electrophoretically separated GP IIb and GP IIIa was studied using a Western blot procedure in the presence of Ca2+, Mg2+, or EDTA. The presence of divalent cations did not increase the reactivity of the antibody with the individual glycoproteins. Overall, our results show that acquired antibodies to IIb-IIIa, such as the IgG L, may predominantly react with complex-dependent determinants.

scholarly journals Ciliomotor circuitry underlying whole-body coordination of ciliary activity in the Platynereis larva

2017 ◽  
Author(s):  
Csaba Verasztó ◽  
Nobuo Ueda ◽  
Luis A. Bezares-Calderón ◽  
Aurora Panzera ◽  
Elizabeth A. Williams ◽  
...  
Keyword(s):  
Beat Frequency ◽  
Ciliary Beat Frequency ◽  
Whole Body ◽  
Ciliary Activity ◽  
Ciliary Beating ◽  
Stop And Go ◽  
Multiciliated Cells ◽  
Platynereis Dumerilii ◽  
Catecholaminergic Cells ◽  
Ciliary Locomotion

AbstractCiliated surfaces harbouring synchronously beating cilia can generate fluid flow or drive locomotion. In ciliary swimmers, ciliary beating, arrests, and changes in beat frequency are often coordinated across extended or discontinuous surfaces. To understand how such coordination is achieved, we studied the ciliated larvae of Platynereis dumerilii, a marine annelid. Platynereis larvae have segmental multiciliated cells that regularly display spontaneous coordinated ciliary arrests. We used whole-body connectomics, activity imaging, transgenesis, and neuron ablation to characterize the ciliomotor circuitry. We identified cholinergic, serotonergic, and catecholaminergic ciliomotor neurons. The synchronous rhythmic activation of cholinergic cells drives the coordinated arrests of all cilia. The serotonergic cells are active when cilia are beating. Serotonin inhibits the cholinergic rhythm, and increases ciliary beat frequency. Based on their connectivity and alternating activity, the catecholaminergic cells may generate the rhythm. The ciliomotor circuitry thus constitutes a stop-and-go pacemaker system for the whole-body coordination of ciliary locomotion.

Voltage-dependence of ciliary activity in the ciliate Didinium nasutum

1995 ◽  
Vol 198 (12) ◽  
pp. 2537-2545 ◽  
Author(s):  
J Pernberg ◽  
H Machemer
Keyword(s):  
Membrane Potential ◽  
Voltage Dependence ◽  
Longitudinal Axis ◽  
Threshold Level ◽  
Swimming Behaviour ◽  
Ciliary Activity ◽  
Frequency Increase ◽  
Cyclic Activity ◽  
Beating Frequency ◽  
Ca2 Channels

In the gymnostome ciliate Didinium nasutum, swimming behaviour depends upon the cyclic activity of about 3000 cilia. The normal beating mode, resulting in forward swimming of the cell, is characterized by a posteriad effective beat (18 left of the longitudinal axis) at a frequency of approximately 15 Hz. Activation of depolarization-sensitive ciliary Ca2+ channels leads to an increase in intracellular Ca2+ concentration and a change in the beating mode. Following rapid reorientation, the effective stroke is anteriad (24 ° right of the longitudinal axis) and the beating frequency is about 26 Hz, resulting in fast backward swimming of the cell. In response to minor depolarizations, and hence small increases in cytoplasmic Ca2+ concentration, the cilia inactivate. Frequency increase and reversal in beat orientation share a single threshold level of membrane potential, since both changes of the beating mode occur simultaneously.

beta-Adrenergic stimulation of respiratory ciliary activity

1980 ◽  
Vol 48 (5) ◽  
pp. 868-871 ◽  
Author(s):  
P. Verdugo ◽  
N. T. Johnson ◽  
P. Y. Tam
Keyword(s):  
Respiratory Epithelium ◽  
Ciliary Activity ◽  
Ciliated Cells ◽  
Adrenergic Stimulation ◽  
Laser Scattering ◽  
Beta Adrenergic ◽  
Ciliary Beating ◽  
Stimulation Of

We investigated the effect of isoproterenol on ciliary activity using a mucus-free preparation of cultured ciliated cells of the rabbit trachea. The frequency of ciliary beating was monitored by dynamic laser-scattering spectroscopy. The results demonstrated that isoproterenol directly stimulates the activity of ciliated cells of the respiratory epithelium and that this effect is beta-adrenergic specific inasmuch as the observed stimulation can be blocked by propranolol.

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