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Blackshaw SE. Experimental approaches to transduction and the receptor potential in muscle receptors. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1992; 58:19-60. [PMID: 1631314 DOI: 10.1016/0079-6107(92)90010-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- S E Blackshaw
- Department of Cell Biology, University of Glasgow, U.K
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2
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Physiological characteristics of the tympanic organ in noctuoid moths. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 1985. [DOI: 10.1007/bf00619118] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Tao-Cheng JH, Hirosawa K, Nakajima Y, Peng HB. Freeze-fracture study of the crayfish stretch receptor. J Comp Neurol 1981; 200:23-38. [PMID: 7251944 DOI: 10.1002/cne.902000103] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The crayfish slow-adapting stretch receptor was fixed under relaxed or stretched conditions (twice the relaxed length) and then processed for freeze-fracture study. The sensory neuron membrane had evenly distributed intramembrane particles mostly on its P face. The density of these particles was higher in the cell body than in the dendritic tips, which are the terminal portions of the dendrites. The dendritic tips were cylindrical under the relaxed condition and showed deformations with stretch stimuli. When they were fixed under the stretched condition with 1.6% glutaraldehyde in 0.12 M phosphate buffer (the total osmolarity of this fixative is isosmotic with the physiological solution), the dendritic tips showed regional swelling and shrinkage. The intramembrane particle density of the swollen parts decreased and there were particle-free patches of membrane, whereas the particle density of the shrunken parts increased. On the other hand when the receptor was fixed with 1.6% glutaraldehyde in 0.2 M phosphate buffer (the total osmolarity is hyperosmotic but buffer osmolarity is isosmotic), the diameter of the dendritic tips became smaller, and their membrane particle densities were almost the same as that under the relaxed condition. The sheath cells covering the sensory neuron were characterized by their sheet-like profiles, gap junctions, and crater-like protrusions. The receptor muscle membrane had longitudinal foldings, occasional invaginations, peripheral couplings, string-shaped particle aggregates, and band-shaped particle aggregates.
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Takahata M. Functional differentiation of crayfish statocyst receptors in sensory adaptation. ACTA ACUST UNITED AC 1981. [DOI: 10.1016/0300-9629(81)90311-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Peetz W, Winter C. Alteration of the excitation state in receptor cells by hemolymph: A new phenomenon in the crayfish stretch receptor. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/0300-9629(80)90408-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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6
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Electrophysiology of trichobothria in orb-weaving spiders (Agelenidae, Araneae). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 1978. [DOI: 10.1007/bf00657345] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Eldred E, Yellin H, DeSantis M, Smith CM. Supplement to bibliography on muscle receptors: their morphology, pathology, physiology, and pharmacology. Exp Neurol 1977; 55:1-118. [PMID: 323027 DOI: 10.1016/0014-4886(77)90360-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Horch KW, Burgess PR. Responses to threshold and suprathreshold stimuli by slowly adapting cutaneous mechanoreceptors in the cat. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 1976. [DOI: 10.1007/bf00659146] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
1. Stretching a frog muscle spindle evoked a discharge of action potentials in its sensory axon. As the rate of this discharge decreased during the adaptation that followed the dynamic phase of a stretch, the variability of the interspike intervals of the impulse train increased.2. Adaptation occurred in two phases. At first the impulse train was almost regular and adapted rapidly, but later this gave way to a phase of slower adaptation where the variability of the discharge was much increased. In the second phase of adaptation the interspike intervals increased in length less than half as quickly as in the first phase.3. When the rate of adaptation changed from the more rapid to the slower phase there was often an abrupt change in the character of the discharge and the relationship between the mean interspike interval and the variability changed. The interspike interval at which this change-over occurred was relatively constant in records of the discharge from one afferent fibre even though stretches of different amplitude were employed, though it differed from one afferent fibre to another.4. These features of the discharge during adaptation suggest that the two sections of the impulse trains were derived from different spike generators by a process of probabilistic mixing.
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Lowe DA, Mill PJ, Knapp MF. The fine structure of the PD proprioceptor of Cancer pagurus. II. The position sensitive cells. PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. SERIES B, BIOLOGICAL SCIENCES 1973; 184:199-205. [PMID: 4148571 DOI: 10.1098/rspb.1973.0043] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The cell bodies of the position sensitive units form a row distal to the movement sensitive cells and their dendrites run in pairs in a narrow neck of tissue on the ventral side of the receptor strand. The scolopidia share the features of elongation and relaxation sensitive movement units. Thus the canal cell is absent, but there is some scolopale material in the enveloping cells. Also the scolopale is apposed by a mixture of strand cells and collagen. The more distal scolopidia are found in a region of large haemocoelic lacunae. The physiological differences between movement and position sensitive units could be explained in terms of how well the dendrites are anchored into the tube; with the position cells possibly being held at different levels with respect to their maximum sensitivity. On the other hand, the dendrites of both types of unit may behave identically and, if so, then the necessary physiological differences could occur in the transduction and/or impulse initiation sites. These alternative explanations are discussed.
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Mill PJ, Lowe DA. The fine structure of the PD proprioceptor of Cancer pagurus. I. The receptor stand and the movement sensitive cells. PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. SERIES B, BIOLOGICAL SCIENCES 1973; 184:179-97. [PMID: 4148570 DOI: 10.1098/rspb.1973.0042] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The propodite-dactylopodite (PD) proprioceptor ofCancer pagurusconsists of a receptor strand in which are embedded the dendrites of up to 80 bipolar nerve cells. The strand is composed of numerous cells and collagen and is surrounded by a thin layer of amorphous connective tissue. Beneath the latter there are often haemocoelic lacunae and individual haemocytes are found surrounded by strand tissue. The sensory cells can be divided into a proximal group with large cell bodies (movement sensitive cells) and a distal row with smaller cell bodies (position sensitive cells). The former can be further divided on the basis of the insertion of their dendrites into the strand. Thus elongation sensitive movement cells (e. s. m. cs) insert into the anterior surface and run in the ventral region of the receptor strand, while relaxation sensitive movement cells (r. s. m. cs) insert into the dorsal surface and run dorsally through the strand. The dendrites run in pairs, the members of each pair being either e. s. m. cs or r. s. m. cs. Each pair is surrounded distally by a scolopidium, consisting of a scolopale cell, two enveloping cells, a tube of extracellular material and, in e. s. m. cs, a canal cell. The scolopale cell contains a scolopale consisting of electron dense material laid down around a matrix of longitudinally oriented microtubules. In e. s. m. cs the enveloping cells also contain aggregations of a similar material. The dendrites make desmosome contacts with the scolopale cell and the corresponding thickenings of the scolopale cell membrane are juxtaposed by scolopale material. Beyond the scolopale the dendrites enter and terminate within a tube of extracellular material. In e. s. m. cs the scolopidium is surrounded mainly by strand cells, but in r. s. m. cs it is surrounded by collagen fibres. Where the collagen fibres meet the sheathing cells there are often contact zones. Other differences between e. s. m. cs and r. s. m. cs occur in the fine structure of the dendrites and these are described. It is suggested that in e. s. m. cs, since the scolopale is apposed by strand cells, stretching of the strand will lead to elongation of the scolopale and hence of the dendritic terminals. In contrast, in r. s. m. cs, it is possible that the scolopidium is not stretched during elongation of the strand, since there is little cellular contact between the two, but that during strand relaxation the energy stored in the collagen fibres forces the proximal end of the scolopale away from the more distal regions and hence stretches the dendritic terminations. Previous theories are discussed and compared with this idea. Also the relative merits of mechanical and physiological explanations for the phasic nature of these units are discussed.
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Abstract
Spiking activity of the more sensitive acoustic receptor is described as a function of stimulus intensity. The form of the intensity characteristic depends strongly on stimulus duration. For very brief stimuli, the integral of stimulus power over stimulus duration determines the effectiveness. No response saturation is observed. With longer stimuli (50 msec), a steady firing rate is elicited. The response extends from the spontaneous rate of 20-40 spikes/sec to a saturated firing rate of nearly 700 spikes/sec. The characteristic is monotonic over more than 50 db in stimulus intensity. With very long stimuli (10 sec), the characteristics are nonmonotonic. Firing rates late in the stimulus decrease in response to an increase in stimulus intensity. The non-monotonic characteristics are attributed to intensity-related changes in response adaptation.
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Sokolove PG, Cooke IM. Inhibition of impulse activity in a sensory neuron by an electrogenic pump. J Gen Physiol 1971; 57:125-63. [PMID: 5543415 PMCID: PMC2203078 DOI: 10.1085/jgp.57.2.125] [Citation(s) in RCA: 138] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
THE CRAYFISH TONIC STRETCH RECEPTOR NEURON MANIFESTS THREE PHENOMENA: (a) Impulse frequency in response to a depolarizing current decays exponentially to half the initial rate with a time constant of about 4 sec. (b) One or more extra impulses superimposed on steady activity result in a lengthening of the interspike interval immediately following the last extra impulse which is proportional to the number of extra impulses. However, above a "threshold' number of impulses the proportionality constant becomes abruptly larger. (c) Following trains of impulses, the resting potential of the cell is hyperpolarized by an amount proportional to impulse number. Such posttetanic hyperpolarization (PTH) decays approximately exponentially with a time constant of 11 sec, but this varies with membrane potential. These effects are attributed to the incremental increase of an inhibitory (hyperpolarizing) current with a long (relative to interspike interval) decay constant. We suggest that this inhibitory current is the result of increased electrogenic Na pumping stimulated by Na entering with each impulse. Evidence is presented that the three effects are reversibly inhibited by conditions which depress active Na transport: (a) Li substituted for Na in the bath; (b) application of strophanthidin; (c) K removal; (d) treatment with cyanide; (e) cooling. We conclude that a single process is responsible for the three responses described above and identify that process as electrogenic Na pumping. Our observations also indicate that electrogenic pumping contributes to this neuron's resting potential.
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Grundfest H. The General Electrophysiology of Input Membrane in Electrogenic Excitable Cells. PRINCIPLES OF RECEPTOR PHYSIOLOGY 1971. [DOI: 10.1007/978-3-642-65063-5_4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Teorell T. A Biophysical Analysis of Mechano-electrical Transduction. PRINCIPLES OF RECEPTOR PHYSIOLOGY 1971. [DOI: 10.1007/978-3-642-65063-5_10] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Koike H, Mano N, Okada Y, Oshima T. Repetitive impulses generated in fast and slow pyramidal tract cells by intracellularly applied current steps. Exp Brain Res 1970; 11:263-81. [PMID: 4320005 DOI: 10.1007/bf01474386] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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19
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Variability of adaptational properties of an excitable neuron membrane. NEUROPHYSIOLOGY+ 1969. [DOI: 10.1007/bf01063659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Coillot JP, Boistel J. [Electrical activity along the stretch receptors of the metathoracic leg of the cricket, Schistocerca gregaria]. JOURNAL OF INSECT PHYSIOLOGY 1969; 15:1449-1470. [PMID: 5810616 DOI: 10.1016/0022-1910(69)90204-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Nakajima S, Onodera K. Adaptation of the generator potential in the crayfish stretch receptors under constant length and constant tension. J Physiol 1969; 200:187-204. [PMID: 5761940 PMCID: PMC1350424 DOI: 10.1113/jphysiol.1969.sp008688] [Citation(s) in RCA: 86] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
1. Generator potentials were investigated in stretch receptors of crayfish after abolishing spike potentials with tetrodotoxin.2. The time courses of the decline of generator potential (generator adaptation) were almost the same in the slowly and rapidly adapting receptors.3. The time courses of the tension changes after suddenly stretching the receptor muscles did not differ much between the two receptor types.4. The amplitudes of generator potential per unit stress or per unit strain in the receptor muscle were roughly the same in the two receptor types.5. By comparing generator adaptation under length-clamp and tension-clamp in the slowly adapting receptors, it was suggested that roughly 70% of the generator adaptation could be explained by a simple visco-elastic property of the receptor muscle, when observed for 1 sec after the beginning of the stretch.6. It was concluded that the marked differences in the receptor adaptation between the two receptor types were attributable to the differences in the properties of spike generating membrane rather than to the properties of the generator potentials.7. In each type of receptor, both the generator adaptation and the adaptation of spike generating mechanisms contributed to determining the whole rates of receptor adaptation. In the slowly adapting receptor, however, the generator adaptation seemed more important, while in the rapidly adapting receptor the spike generating mechanisms seemed more important.
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Abstract
The generator potential of both slowly and rapidly adapting crayfish stretch receptor cells can still be elicited by mechanical stimuli when all the Na of the bathing medium is replaced by various organic cations. In the presence of tris(hydroxymethyl)aminomethane (Tris), the generator potential is particularly large, about 30-50 % of that in the control saline, while spike electrogenesis of the cell is abolished. Persistence of the generator response is not due to retention of Na by a diffusion barrier, and ionic contributions to the electrogenesis by Ca and Cl can also be excluded. Thus, whereas the electrogenesis of the generator membrane must be due to an increased permeability to monovalent cations, the active receptor membrane appears to be less selective for different monovalent cations than is the receptor component of some other cells, or the conductile component of the stretch receptor neuron.
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Obara S, Grundfest H. Effects of lithium on different membrane components of crayfish stretch receptor neurons. J Gen Physiol 1968; 51:635-54. [PMID: 5654404 PMCID: PMC2201213 DOI: 10.1085/jgp.51.5.635] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Unlike several other varieties of input membrane, that of the crayfish stretch receptor develops a generator potential in response to stretch when all the Na of the medium is replaced with Li. However, Li depolarizes the receptor neuron, the soma membrane becoming more depolarized than that of the axon. During exposure to Li the cell usually fires spontaneously for a period, and when it becomes quiescent spike electrogenesis fails in the soma but persists in the axon. These effects are seen in the rapidly adapting as well as the slowly adapting cells. The block of spike electrogenesis of the soma membrane is only partly due to the Li-induced depolarization and a significant role must be ascribed to a specific effect of Li.
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Grundfest H. Tetrodotoxin: Action on Graded Responses. Science 1967. [DOI: 10.1126/science.156.3783.1771-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Harry Grundfest
- Department of Neurology, College of Physicians and Surgeons, Columbia University. New York, New York
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Grundfest H. Tetrodotoxin: Action on Graded Responses. Science 1967. [DOI: 10.1126/science.156.3783.1771.a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Harry Grundfest
- Department of Neurology, College of Physicians and Surgeons, Columbia University. New York, New York
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Nakajima S, Takahashi K. Post-tetanic hyperpolarization and electrogenic Na pump in stretch receptor neurone of crayfish. J Physiol 1966; 187:105-27. [PMID: 4226418 PMCID: PMC1395969 DOI: 10.1113/jphysiol.1966.sp008078] [Citation(s) in RCA: 166] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
1. Two types of after-potentials in the stretch receptor neurone of crayfish are described.2. A short-duration after-hyperpolarization associated with a single spike or a few spikes is diminished and reversed on applying hyperpolarizing currents. However, a much longer-lasting post-tetanic hyperpolarization (PTH) is enhanced by conditioning hyperpolarization; thus, no reversal potential can be obtained.3. No changes in membrane conductance occur during PTH.4. Reducing K concentration in the bathing fluid diminishes PTH, while it shifts the reversal potential of the short after-potential toward greater negativity.5. Replacement of Na with Li, or addition of 2,4-dinitrophenol in the bathing fluid suppresses PTH in a reversible manner.6. Electrophoretic injection of Na into the cell induces a long-lasting hyperpolarization.7. No change in K-equilibrium potential, as indicated by the reversal point of the short after-potential, is detected during PTH.8. It is concluded that the short after-potential is caused by a permeability increase for potassium ion, whereas PTH is produced by an electrogenic Na-pump.
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Brown MC, Stein RB. Quantitative studies on the slowly adapting stretch receptor of the crayfish. KYBERNETIK 1966; 3:175-85. [PMID: 5982097 DOI: 10.1007/bf00290253] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
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Grundfest H. Heterogeneity of excitable membrane: electrophysiological and pharmacological evidence and some consequences. Ann N Y Acad Sci 1966; 137:901-49. [PMID: 5229836 DOI: 10.1111/j.1749-6632.1966.tb50208.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Thorson J. Small-signal analysis of a visual reflex in the locust. II. Frequency dependence. KYBERNETIK 1966; 3:53-66. [PMID: 6003992 DOI: 10.1007/bf00299898] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Abstract
1. An analysis is made of the transmission of mechanical forces through the Pacinian corpuscle. In particular, forces are analysed which produce pressure differences at the centre of the corpuscle and lead to excitation of the sensory nerve ending.2. The main structural elements in force transmission through the corpuscle are the lamellae, their interconnexions, and the interlamellar fluid. The two former provide the elastic elements and constraint for the fluid; and the latter, the viscous elements. The mechanical equivalent incorporating these elements is a system of dashpots (the lamellar surfaces and the interlamellar fluid) and springs (the lamellae and their interconnexions); it is a mechanical filter which suppresses low frequencies. The dynamic and static patterns of lamella displacements in the equivalent are in close agreement with those observed in Pacinian corpuscles.3. Steady-state and transient pressure fields were determined for the equivalent. Under static compression, only elastic forces exist in the corpuscle. Analysis shows that such forces are transmitted poorly from periphery to centre through the lamellated structure. The compliance of the lamellar interconnexions is so high in relation to that of the lamellae themselves, that most of the pressure load is carried by the outer lamellae. As a result, only a small fraction of the steady-state pressure at the outer surface reaches the centre of the corpuscle where the sensory ending is located. This is the mechanical basis of receptor adaptation.4. Under dynamic compression, viscous forces develop in the corpuscle; and these account for most of the pressure at times too early for development of elastic deformations. Analysis shows that such forces are transmitted well. For example, if a typical corpuscle of 500mu diameter is compressed by 20mu linearly during 2 msec, the pressure differences near to the centre of the corpuscle are initially as high as at the periphery, and stay within the same order throughout the process of compression. In general, pressure at the centre increases steeply with velocity of compression. This explains the marked velocity dependence of the generator response of the sensory ending.If, in the foregoing example, the 20mu compression is held fixed after 2 msec, the pressure differences at the centre fall abruptly to near zero with the onset of the static phase. The duration of pressure transients at the centre approximates that of the ;active' phase of the generator current of the sensory ending derived from experiments, as expected in a causal relationship: pressure difference --> generator current. Taken together with the earlier experimental finding of marked prolongation of generator response in corpuscles partially stripped of lamellae (Loewenstein & Mendelson, 1965), this result warrants the conclusion that the mechanical filter action of the corpuscle is the rate-limiting factor in generator response adaptation.5. When the corpuscle is released from compression, energy stored in the elastic elements during compression is released and consumed in viscous flow. Thus, viscous pressure is produced anew. The magnitude of this pressure depends on the velocity of release. The pressure distribution is rotated by 90 degrees with respect to that in compression; i.e. during release, compression occurs once again, but this time at right angles to the direction of initial compression. Experiments show that the sensory ending does not discriminate such a rotation; the polarity and order of magnitude of the generator response to compression in one plane are the same as in another. Analysis shows that considerable pressure differences may be developed at the centre of the corpuscle during releases at physiological velocities. For instance, in a passive return from a compression of 20mu, the pressure difference at the centre (and the generator current) is of the same order of magnitude as that in a compression of the velocity in 4. This accounts for the ;off'-response of the sensory ending in purely mechanical terms.
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Grundfest H. Comparative electrobiology of excitable membranes. ADVANCES IN COMPARATIVE PHYSIOLOGY AND BIOCHEMISTRY 1966; 2:1-116. [PMID: 5330181 DOI: 10.1016/b978-0-12-395511-1.50006-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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