Neural Control of the Male Photuris Versicolor Firefly Flash

1981 ◽  
Vol 92 (1) ◽  
pp. 165-172
Author(s):  
ALBERT D. CARLSON
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Neural Control ◽  
Ventral Nerve Cord ◽  
Temperature Coefficients ◽  
Wide Range ◽  
The Central Nervous System ◽  
Oscillatory Character ◽  
Lower Temperature ◽  
Stimulation Of

1. Continuous electrical stimulation of the ventral nerve cord or the lantern of the decapitated male Photuris versicolor firefly over a wide range of stimulus frequencies can produce a flash that is multi-peaked, like the courtship flash of this species. The central nervous system does not shape these stimulated compound flashes because they can be induced in deganglionated posterior lantern segments. 2. The stimulated compound flashes show a fixed oscillatory character with peak frequencies independent of stimulation frequency. They can be generated by individual lantern areas. Compared with the peaks of courtship flashes the peaks of stimulated flashes show higher frequency, significantly lower temperature coefficients (Q)10, and incomplete extinction. 3. P. lucicrescens males produce a courtship flash that has a single peak and their lanterns respond to continuous stimulation with an unstructured glow.

scholarly journals Central nervous system modulates the neuromechanical delay in a broad range for the control of muscle force

2018 ◽  
Vol 125 (5) ◽  
pp. 1404-1410 ◽  
Author(s):  
A. Del Vecchio ◽  
A. Úbeda ◽  
M. Sartori ◽  
J. M. Azorín ◽  
F. Felici ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Motor Unit ◽  
Neural Coding ◽  
Neural Control ◽  
Motor Units ◽  
Force Generation ◽  
Neural Drive ◽  
Wide Range ◽  
The Central Nervous System

Force is generated by muscle units according to the neural activation sent by motor neurons. The motor unit is therefore the interface between the neural coding of movement and the musculotendinous system. Here we propose a method to accurately measure the latency between an estimate of the neural drive to muscle and force. Furthermore, we systematically investigate this latency, which we refer to as the neuromechanical delay (NMD), as a function of the rate of force generation. In two experimental sessions, eight men performed isometric finger abduction and ankle dorsiflexion sinusoidal contractions at three frequencies and peak-to-peak amplitudes {0.5, 1, and 1.5 Hz; 1, 5, and 10 of maximal force [%maximal voluntary contraction (MVC)]}, with a mean force of 10% MVC. The discharge timings of motor units of the first dorsal interosseous (FDI) and tibialis anterior (TA) muscle were identified by high-density surface EMG decomposition. The neural drive was estimated as the cumulative discharge timings of the identified motor units. The neural drive predicted 80 ± 0.4% of the force fluctuations and consistently anticipated force by 194.6 ± 55 ms (average across conditions and muscles). The NMD decreased nonlinearly with the rate of force generation ( R2 = 0.82 ± 0.07; exponential fitting) with a broad range of values (from 70 to 385 ms) and was 66 ± 0.01 ms shorter for the FDI than TA ( P < 0.001). In conclusion, we provided a method to estimate the delay between the neural control and force generation, and we showed that this delay is muscle-dependent and is modulated within a wide range by the central nervous system. NEW & NOTEWORTHY The motor unit is a neuromechanical interface that converts neural signals into mechanical force with a delay determined by neural and peripheral properties. Classically, this delay has been assessed from the muscle resting level or during electrically elicited contractions. In the present study, we introduce the neuromechanical delay as the latency between the neural drive to muscle and force during variable-force contractions, and we show that it is broadly modulated by the central nervous system.

scholarly journals VI. —Anaphylaxis and anaphylatoxins

1923 ◽  
Vol 211 (382-390) ◽  
pp. 273-315 ◽  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Guinea Pig ◽  
Anaphylactic Shock ◽  
The Body ◽  
Muscle Fibres ◽  
Direct Stimulation ◽  
Fundamental Conception ◽  
The Central Nervous System ◽  
Stimulation Of

In the study of the phenomena of anaphylaxis there are certain points on which some measure of agreement seems to have been attained. In the case of anaphylaxis to soluble proteins, with which alone we are directly concerned in this paper, the majority of investigators probably accept the view that the condition is due to the formation of an antibody of the precipitin type. Concerning the method, however, by which the presence of this antibody causes the specific sensitiveness, the means by which its interaction with the antibody produces the anaphylactic shock, there is a wide divergence of conception. Two main currents of speculation can be discerned. One view, historically rather the earlier, and first put forward by Besredka (1) attributes the anaphylactic condition to the location of the antibody in the body cells. There is not complete unanimity among adherents of this view as to the nature of the antibody concerned, or as to the class of cells containing it which are primarily affected in the anaphylactic shock. Besredka (2) himself has apparently not accepted the identification of the anaphylactic antibody with a precipitin, but regards it as belonging to a special class (sensibilisine). He also regards the cells of the central nervous system as those primarily involved in the anaphylactic shock in the guinea-pig. Others, including one of us (3), have found no adequate reason for rejecting the strong evidence in favour of the precipitin nature of the anaphylactic antibody, produced by Doerr and Russ (4), Weil (5), and others, and have accepted and confirmed the description of the rapid anaphylactic death in the guinea-pig as due to a direct stimulation of the plain-muscle fibres surrounding the bronchioles, causing valve-like obstruction of the lumen, and leading to asphyxia, with the characteristic fixed distension of the lungs, as first described by Auer and Lewis (6), and almost simultaneously by Biedl and Kraus (7). But the fundamental conception of anaphylaxis as due to cellular location of an antibody, and of the reaction as due to the union of antigen and antibody taking place in the protoplasm, is common to a number of workers who thus differ on details.

scholarly journals On The Hormonal and Neural Control of the Release of Gametes in Ascidians

1951 ◽  
Vol 28 (4) ◽  
pp. 463-472
Author(s):  
D. B. CARLISLE
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Neural Control ◽  
Sense Organ ◽  
Chorionic Gonadotrophin ◽  
Gamete Release ◽  
The Central Nervous System ◽  
Neural Region

1. It is argued that the neural gland (+ciliated pit) of ascidians is homologous with the entire pituitary of vertebrates, adenohypophysis as well as neurohypophysis. 2. Ciona and Phallusia are shown to respond to an injection of chorionic gonadotrophin by the release of gametes. 3. They respond in the same way to feeding with eggs and sperm of their own species but not to those of other species. 4. This response is prevented in both cases by section of the nerves from the ganglion to the region of the gonads. 5. Destruction of the heart and removal of the blood does not prevent the response to feeding with gametes, nor to injection of gonadotrophin into the neural region; this operation does prevent the reaction if the site of injection is elsewhere. 6. Destruction of the neural gland, leaving the ganglion intact, prevents the response to feeding with gametes, but does not prevent its following an injection of chorionic gonadotrophin. 7. The hypothesis is advanced that the neural gland (+ciliated pit) is the sense organ involved in this response to feeding, and that it produces gonadotrophin and passes it to the ganglion by a non-vascular route; the ganglion then stimulates by nervous pathways the gonads to release gametes. 8. It is suggested that gonadotrophin is here fulfilling a sensory role in passing information from sense organ to the central nervous system. It may be contrasted with adrenalin which passes instructions from the central nervous system to effectors. 9. Phallusia is shown to respond with gamete release to an injection of an extract of the neural complex of Ciona.

scholarly journals Distribution of the prion protein in sheep terminally affected with BSE following experimental oral transmission

2001 ◽  
Vol 82 (10) ◽  
pp. 2319-2326 ◽  
Author(s):  
J. D. Foster ◽  
D. W. Parnham ◽  
N. Hunter ◽  
M. Bruce
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Experimental Infection ◽  
Oral Route ◽  
Similar Distribution ◽  
Peripheral Tissues ◽  
Oral Transmission ◽  
Wide Range ◽  
Direct Contrast ◽  
The Central Nervous System

This study has examined the distribution of PrPSc in sheep by immunocytochemistry of tissues recovered from terminally affected animals following their experimental infection by the oral route with BSE. Despite a wide range of incubation period lengths, affected sheep showed a similar distribution of high levels of PrPSc throughout the central nervous system. PrPSc was also found in the lymphoid system, including parts of the digestive tract, and some components of the peripheral nervous system. These abundant PrPSc deposits in sheep in regions outside the central nervous system are in direct contrast with cattle infected with BSE, which show barely detectable levels of PrPSc in peripheral tissues. A number of genetically susceptible, challenged animals appear to have survived.

Blood Pressure and Pulse Rate in the Foetal Sheep

1945 ◽  
Vol 22 (1-2) ◽  
pp. 63-74
Author(s):  
JOSEPH BARCROFT ◽  
D. H. BARRON
Keyword(s):  
Blood Pressure ◽  
Central Nervous System ◽  
Nervous System ◽  
Pulse Rate ◽  
Umbilical Artery ◽  
The Central Nervous System ◽  
The Right ◽  
First Moment ◽  
Left Vagus ◽  
Stimulation Of

1. A method (the needle method) is described for the measurement of the pressure in the stream going through a vessel. 2. In the foetal sheep the needle method applied to the umbilical artery gives substantially the same results as the mercurial manometer applied to the carotid, until about half-way through the gestation period. 3. As gestation proceeds the needle method applied at the first moment at which it can be applied to the umbilical artery (or a branch) gives readings substantially lower, and increasingly lower as gestation proceeds, than does the mercurial manometer read at the first moment at which it can be read. 4. The discrepancy is due to the sum of a number of causes which are discussed, but of these the most important is an actual rise of pressure between the time of delivery and the completion of the dissections contingent on the use of the mercurial manometer. 5. The cause of this is not at present demonstrated, but either or both of two factors may be concerned: (a) a dulling of the central nervous system which weakens the depressor reflex; (b) the establishment of a greater degree of vasomotor tone consequent on the bombardment of the central nervous system with sensory stimuli. 6. The pulse rates in utero and just after delivery of the foetus into a saline bath at 39-40°C. (the umbilical circulation being unimpaired) are not significantly different. 7. The pulse rate quickens up to the 70th-80th day, after which it becomes slower as gestation proceeds. 8. If both vagi be severed, the pulse rate te to quicken throughout gestation. The pulse, therefore, comes increasingly under vagus inhibition from the 80th-90th day onwards. 9. Even after the vagi have been cut after the 120th day (it has not been tried before) adrenalin in sufficient quantity will cause a further quickening of the pulse. 10. The earliest date at which stimulation of the peripheral end of the right vagus was observed to slow the heart was the 77th day. On the 85th day peripheral stimulation of the left vagus also failed, but succeeded on the 101st day. 11. Central stimulation of the left vagus, with the right vagus intact, produced slowing on the 77th day. 12. Slowing of the heart synchronous with rise of arterial pressure has been observed on the 111th day. 13. Slowing of the heart which bears evidence of being reflex has been obtained by raising the blood pressure (clamping the cord) on the 121st day and by injection of adrenalin on the 118th day. 14. Approaching term both the carotid sinus and cardiac depressor mechanisms are functional. 15. Lowering of the blood pressure as the result of stimulation of the central end of the vagus and with both vagi severed can be demonstrated late in gestation.

Distribution of gamma-aminobutyric acid (GABA) in the central nervous system of the male mud crab, Scylla olivacea

Crustaceana ◽  
2020 ◽  
Vol 93 (9-10) ◽  
pp. 1123-1134
Author(s):  
Kanjana Khornchatri ◽  
Jirawat Saetan ◽  
Sirirak Mukem ◽  
Prasert Sobhon ◽  
Tipsuda Thongbuakaew
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Distribution Pattern ◽  
Nerve Cord ◽  
Ventral Nerve Cord ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Mud Crab ◽  
Decapod Crustaceans ◽  
The Central Nervous System

Abstract Gamma-aminobutyric acid (GABA) is a neurotransmitter that is widely spread in vertebrate and invertebrate nervous systems and modulates essential physiological roles. Previous studies have reported the distribution of several neurotransmitters throughout the central nervous system (CNS) of decapod crustaceans. However, the existence and distribution of GABA in the mud crab’s, Scylla olivacea, CNS has still not been reported. In this study, we investigated the distribution of GABA using immunohistochemistry. The result revealed that GABA immunoreactivity (-ir) was observed in neurons and fibres throughout the CNS, including the eyestalk, brain, and ventral nerve cord of S. olivacea. Therefore, the existence and extensive distribution pattern of GABA in the CNS of the male mud crab suggest its possible roles in feeding, locomotion, and also reproduction.

scholarly journals Magnetic Iron Oxide Nanoparticles: Synthesis, Characterization and Functionalization for Biomedical Applications in the Central Nervous System

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 465 ◽  
Author(s):  
Shoeb Ansari ◽  
Eleonora Ficiarà ◽  
Federico Ruffinatti ◽  
Ilaria Stura ◽  
Monica Argenziano ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Magnetic Iron Oxide Nanoparticles ◽  
Close Link ◽  
Wide Range ◽  
Methods Of Synthesis ◽  
The Central Nervous System

Magnetic Nanoparticles (MNPs) are of great interest in biomedicine, due to their wide range of applications. During recent years, one of the most challenging goals is the development of new strategies to finely tune the unique properties of MNPs, in order to improve their effectiveness in the biomedical field. This review provides an up-to-date overview of the methods of synthesis and functionalization of MNPs focusing on Iron Oxide Nanoparticles (IONPs). Firstly, synthesis strategies for fabricating IONPs of different composition, sizes, shapes, and structures are outlined. We describe the close link between physicochemical properties and magnetic characterization, essential to developing innovative and powerful magnetic-driven nanocarriers. In conclusion, we provide a complete background of IONPs functionalization, safety, and applications for the treatment of Central Nervous System disorders.

scholarly journals Drugs modulating the L-arginine:NO:cGMP pathway – current use in therapy

2016 ◽  
Vol 29 (1) ◽  
pp. 14-20 ◽  
Author(s):  
Magdalena Polakowska ◽  
Jolanta Orzelska-Gorka ◽  
Sylwia Talarek
Keyword(s):  
Nitric Oxide ◽  
Central Nervous System ◽  
Nervous System ◽  
Cardiovascular Diseases ◽  
Significant Role ◽  
Current Understanding ◽  
Physiological Processes ◽  
Wide Range ◽  
The Central Nervous System ◽  
Pharmacological Profiles

AbstractNitric oxide (NO) is a relatively novel messenger that plays a significant role in a wide range of physiological processes. Currently, it is known that, both, lack and excess of NO can cause diseases, thus a lot of substances have been discovered and utilized which can change the concentration of this molecule within the organism. The aim of the present work is to provide an overview of currently used agents modulating the L-arginine:NO:cGMP pathway, as well as to summarize current understanding of their pharmacological profiles. Nowadays, most of these agents are employed particularly in the treatment of cardiovascular diseases. Further studies can hold promise for enhancing the therapeutic equipment for a variety of other impairments, such as osteoporosis, and also in treatments of the central nervous system.

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