THE BIOELECTRIC POTENTIALS OF PLANTS AND THEIR FUNCTIONAL SIGNIFICANCE: IV. CHANGES IN THE RATE OF WATER ABSORPTION IN EXCISED STEMS OF ACER SACCHARUM INDUCED BY APPLIED ELECTROMOTIVE FORCES: THE "FLUSHING EFFECT"

1962 ◽  
Vol 40 (3) ◽  
pp. 405-413 ◽  
Author(s):  
D. S. Fensom
Keyword(s):  
Electrical Stimulation ◽  
Functional Significance ◽  
Acer Saccharum ◽  
The Other ◽  
Streaming Potentials ◽  
Artificial Flow ◽  
Flow Through ◽  
Temporary Disturbance ◽  
Bioelectric Potentials ◽  
Stimulation Of

Experiments on excised stems of maple (Acer saccharum Marsh) in the winter and growing states have shown that artificial flow through open channels can alter the existing biopotential and thus produce local streaming potentials. On the other hand, artificially applied voltages could produce two effects: a small and temporary disturbance in flow which appeared to be electroosmotic in nature and direction: a sudden large surge of flow into the stem after prolonged electrical stimulation of up to 45,000 mv. The latter effect was called "flushing" and only occurred in young green stems which had previously been well exposed to sunlight. Artificial guttation was found to be associated with flushing.

SECRETION OF FSH AND LH IN THE PSEUDOPREGNANT RAT

1965 ◽  
Vol 49 (3) ◽  
pp. 370-378 ◽  
Author(s):  
G. P. van Rees ◽  
C. A. de Groot
Keyword(s):  
Electrical Stimulation ◽  
Adult Female ◽  
The Other ◽  
Female Rats ◽  
Cervix Uteri ◽  
Similar Increase ◽  
Clear Cut ◽  
Inhibiting Effect ◽  
Pituitary Glands ◽  
Stimulation Of

ABSTRACT The pituitary LH- and FSH-content was estimated in rats made pseudopregnant by electrical stimulation of the cervix uteri; serum FSH was also estimated. An increase in both FSH- and LH-content was found, which was largest in the pituitary glands collected on the 7th day of pseudopregnancy. A similar increase in pituitary LH-content could be induced in normal adult female rats by a course of injections of 5 mg of progesterone daily. Serum FSH-levels did not show any clear-cut changes during pseudopregnancy, but rose at the end of it. In the discussion a connection is made between the similarity of the result of progesterone treatment and pseudopregnancy on one hand and between the ovulation-inhibiting effect of progesterone and its ability to increase pituitary FSH-and LH-levels on the other.

scholarly journals Submicroscopic Changes of the Nerve Endings in the Adrenal Medulla after Stimulation of the Splanchnic Nerve

1957 ◽  
Vol 3 (4) ◽  
pp. 611-614 ◽  
Author(s):  
Eduardo De Robertis ◽  
Alberto Vaz Ferreira
Keyword(s):  
Electrical Stimulation ◽  
Electron Microscope ◽  
Adrenal Medulla ◽  
Synaptic Vesicles ◽  
Splanchnic Nerve ◽  
The Other ◽  
Nerve Endings ◽  
The Mean ◽  
Increased Activity ◽  
Stimulation Of

The nerve endings of the adrenal medulla of the rabbit were studied under the electron microscope in the normal condition and after prolonged electrical stimulation of the splanchnic nerve. With a stimulus of 100 pulses per second for 10 minutes, there is an increase in the number of synaptic vesicles in the nerve ending. The mean number is of 82.6 vesicles per square micron in the normal and of 132.7 per square micron in the stimulated glands. With a stimulus of 400 pulses per second for 10 minutes, there is a considerable depletion of synaptic vesicles and other changes occur in the nerve endings. The mean number of vesicles is of 29.2 per square micron. These results are interpreted as indicative of an increased activity of the ending in one case, and as a diminished activity and fatigue of the synaptic junction in the other.

Modification in activity of medullary respiratory-related neurons for vocalization and swallowing

1994 ◽  
Vol 71 (6) ◽  
pp. 2294-2304 ◽  
Author(s):  
C. R. Larson ◽  
Y. Yajima ◽  
P. Ko
Keyword(s):  
Electrical Stimulation ◽  
Vocal Fold ◽  
Discharge Rate ◽  
The Other ◽  
Nucleus Ambiguus ◽  
Macaca Nemestrina ◽  
Deep Inspiration ◽  
Subglottal Pressure ◽  
Posterior Cricoarytenoid ◽  
Stimulation Of

1. The medullary ventral respiratory group (VRG) in and near the nucleus ambiguus contains neurons related to respiration. Also found here are neurons related to vocalization and swallowing as well as motoneurons of laryngeal, pharyngeal, palatal, and esophageal muscles. Previous reports in anesthetized animals have characterized discharge properties of neurons as they relate to a single behavior, e.g., respiration. Relatively few studies have documented discharge properties during more than one behavior, e.g., respiration and swallowing. Neurons were recorded extracellularly from awake Macaca nemestrina monkeys engaged in a vocalization task. The present paper describes how respiratory-related neurons (RRNs) modify their discharge during vocalization and swallowing. 2. The temporal relation between vocalization, subglottal pressure (SP), and diaphragm electromyogram (EMG) was established from recordings in anesthetized monkeys. Vocalization was elicited by electrical stimulation of the midbrain periaqueductal gray (PAG). Vocalization is preceded by deep inspiration and a brief pause in diaphragm EMG and begins with a rapid increase in positive SP. 3. Extracellularly recorded neural potential from the VRG in three awake monkeys were related to respiration by correlating their discharge with EMGs from the posterior cricoarytenoid or intercostal muscles during quiet respiration. Neurons were classified as inspiratory (INSP; N = 27), phase spanning (PS; N = 20), or expiratory (N = 6) on this basis. 4. A fourth category of cells was defined as a subgroup of INSP cells on the basis of their discharge during vocalization. This group, inspiratory-pause (INSP-PS; N = 10), paused for approximately 100 ms just before vocalization and resumed their activity during vocalization. 5. Of 63 fully analyzed RRNs, 40 (63%) also modulated their activity with vocalization and 3 (5%) with swallowing. Thirteen (21%) RRNs modulated with vocalization, respiration, and swallowing. Seven (11%) cells were modulated only with respiration. 6. Most cells demonstrated a shorter period of activity and a higher discharge rate associated with vocalization in comparison with quiet respiration. Six (30%) of the PS cells demonstrated an augmenting discharge pattern before vocalization, which was different from the other PS cells and different from their pattern during quiet respiration. Thirteen RRNs showed a pause in activity during vocal fold closure associated with swallowing, whereas three cells gave a burst at this time. 7. The higher discharge rate and shorter burst duration preceding vocalization, compared with quiet respiration, may be related to the greater positive SP necessary to support vocalization.(ABSTRACT TRUNCATED AT 400 WORDS)

Responses of neurons in VPL and VPL-VL region of the cat to algesic stimulation of muscle and tendon

1983 ◽  
Vol 49 (3) ◽  
pp. 649-661 ◽  
Author(s):  
K. D. Kniffki ◽  
K. Mizumura
Keyword(s):  
Electrical Stimulation ◽  
Mechanical Stimulation ◽  
Receptive Fields ◽  
Transitional Zone ◽  
The Other ◽  
Group Iii ◽  
Group I ◽  
Nociceptive Information ◽  
Noxious Mechanical Stimulation ◽  
Stimulation Of

1. The responses evoked by electrical stimulation of cutaneous and muscle nerves, by noxious and innocuous mechanical stimulation of muscle, tendon, and cutaneous tissues, and by intra-arterial (ia) injection of algesic substances (potassium, bradykinin) into arteries supplying the gastrocnemius-soleus muscle (GS) were studied in single neurons located in the ventroposterolateral nucleus (VPL) and in the transitional zone between VPL and the ventrolateral nucleus (VL) of cats lightly anesthetized with thiopenthal. Such chemical stimulation of the muscles has been shown to activate muscular groups III and IV axons specifically (43, 44) and presumably is nociceptive in character (14, 17, 31). 2. One hundred eight neurons were tested. Eighty-three of the units responded only to various types of cutaneous stimulation of the hindlimb. The other 25 responded to algesic stimulation of muscle and/or tendon. Of these latter 25, 7 had no apparent cutaneous receptive field although 4 of them responded to electrical stimulation of the common peroneal and/or sural nerve. Thus, only three neurons responded exclusively to algesic chemical and noxious mechanical stimulation of the muscle. Of the other 18 neurons, 14 had cutaneous receptive fields restricted to the hindlimb and often responded to non-noxious repetitive light stroking and to noxious pinching with a high-frequency discharge. Four cells (two of which had cutaneous input only from low-threshold mechanoreceptors) had complex and large receptive fields extending to more than one limb. 3. Potassium was a more potent muscle receptor stimulant than bradykinin, the latter only weakly exciting 3 neurons of 24 tested with both substances. The responses to potassium were rapid (approximately 4.0 s in latency) and tended to be greater (have higher response rates) for the units that responded to cutaneous as well as muscle/tendon stimulation. 4. Most neurons that responded to noxious deep stimulation had a threshold for the GS nerve volley in the group III fiber range. The few neurons with thresholds slightly below the group III range did not respond to activation of group I or II muscle spindle afferents by intra-arterial application of succinylcholine or by stretching the muscle. 5. Neurons with responses to any of the muscle, tendon, or cutaneous nociceptive stimuli were located at the ventral and dorsal periphery of VPL and in the VPL-VL transitional zone. 6. These results strongly suggest that there exist regions within the lateral diencephalon of cats that are capable of processing nociceptive information and that these regions are located at the periphery of VPL.

scholarly journals ON THE RELATION OF DIRECT CURRENTS TO CONDENSER DISCHARGES AS STIMULI

1935 ◽  
Vol 18 (5) ◽  
pp. 755-766 ◽  
Author(s):  
H. A. Blair
Keyword(s):  
Differential Equation ◽  
Electrical Stimulation ◽  
The Other ◽  
The One ◽  
Stimulation Of

Data on the electrical stimulation of sciatic-gastrocnemius preparations of the frog by both direct currents and condenser discharges at the same time are discussed in relation to the validity of the differential equation See PDF for Equation where p is the local excitatory process, V the stimulating current or voltage, and K and k are constants. It is concluded that the constant k is the same whether it is derived from the data of the one stimulus or the other when the same fibres are being stimulated.

Bacteriology of Electrically Stimulated and Unstimulated Rabbit, Pork, Lamb and Beef Carcasses

1980 ◽  
Vol 43 (9) ◽  
pp. 686-693 ◽  
Author(s):  
B. MRIGADAT ◽  
G. C. SMITH ◽  
T. R. DUTSON ◽  
L. C. HALL ◽  
M. O. HANNA ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Ground Beef ◽  
Skin Surface ◽  
The Other ◽  
Plate Count ◽  
Supraspinatus Muscle ◽  
Beef Carcasses ◽  
Aerobic Plate Count ◽  
Stimulation Of

Electrical stimulation of rabbit muscles caused a reduction in count of Pseudomonas putrefaciens and of a Lactobacillus sp. when inoculated muscles were held for 45 min after electrical stimulation. Little if any change in count was detected on rabbit muscles immediately after electrical stimulation and after 20 min of storage. Electrical stimulation (ES) of pork carcasses did not affect the aerobic plate count (APC) of the skin surface. APC of cutaneous trunci from electrically stimulated sides of beef and lamb carcasses were similar to those of muscles from unstimulated sides or carcasses. APC of ground beef and blade steaks fabricated pre-rigor from electrically stimulated sides were often numerically lower after 3 days of storage than those of corresponding samples from unstimulated sides. Differences in APC between conventional and ES samples of ground beef prepared from vacuum packaged top round were significant (P < 0.05) after 6 days of storage. However, none of the other differences in count were statistically significant (P < 0.05). Electrical stimulation did not cause any consistent substantial changes in microbial types of ground beef, blade steaks, T-bone steaks or rib steaks. When minced, aseptically excised supraspinatus muscle was inoculated with either P. putrefaciens or a Lactobacillus sp., counts of these species in tissues from electrically stimulated beef often were significantly lower than those of corresponding unstimulated samples.

scholarly journals Submandibular secretory and vascular responses to stimulation of the parasympathetic innervation in anesthetized cats

2000 ◽  
Vol 89 (5) ◽  
pp. 1964-1970 ◽  
Author(s):  
K. Rourke ◽  
A. V. Edwards
Keyword(s):  
Blood Flow ◽  
Electrical Stimulation ◽  
Sodium Concentration ◽  
Lingual Nerve ◽  
Parasympathetic Innervation ◽  
Vascular Responses ◽  
Endothelin 1 ◽  
Flow Through ◽  
Submandibular Saliva ◽  
Stimulation Of

Submandibular secretory responses to stimulation of the parasympathetic chorda-lingual nerve in anaesthetized cats have been investigated before, during, and after intracarotid infusion of endothelin-1 (ET-1), which reduced blood flow through the gland by 64 ± 7%. Stimulation at different frequencies (2, 4, 8, and 16 Hz) evoked a frequency-dependent increase in the flow of submandibular saliva, sodium concentration and output, and output of both potassium and protein. The reduction in submandibular blood flow, which occurred in response to the infusion of ET-1, was associated with a decreased flow of saliva and a diminished output of both sodium and protein. The flow of saliva was linearly related to submandibular blood flow both in the presence and absence of ET-1. It is concluded that submandibular secretory responses to electrical stimulation of the parasympathetic innervation can be significantly attenuated by reducing the blood flow through the gland by ET-1 infusion, just as it is when the blood flow is reduced by hypotension.

The effect of temperature on the responses to electrical stimulation of the isolated cerebral cortex of the cat

1969 ◽  
Vol 47 (9) ◽  
pp. 747-753
Author(s):  
J. P. Harwood ◽  
H. D. Sanders
Keyword(s):  
Cerebral Cortex ◽  
Electrical Stimulation ◽  
Low Temperature ◽  
Differential Effect ◽  
The Other ◽  
Effect Of Temperature ◽  
Induced Responses ◽  
Isolated Cortex ◽  
Separate Identity ◽  
Stimulation Of

The effect of temperature over the range 28 to 37 °C was studied on the electrically induced responses in the neuronally isolated cortex of the cat. The positive burst response (PBR) was found to be insensitive to a fall in temperature with no change in threshold, although the duration of the response was increased at low temperature. The threshold for inducing the epileptiform afterdischarge (EAD) remained constant in some animals but decreased in half of the animals studied. As the temperature was lowered, the amplitude of the EAD decreased while the frequency increased. The epileptiform sustaining response (ESR) on the other hand was markedly sensitive to temperature and disappeared around 32 °C. The differential effect of temperature upon the PBR and ESR, which have similar parameters for their production, provides further evidence for the separate identity of the two responses.

Binocular convergence of excitatory and inhibitory synaptic pathways onto neurons of cat visual cortex

1990 ◽  
Vol 4 (6) ◽  
pp. 625-629 ◽  
Author(s):  
David Ferster
Keyword(s):  
Electrical Stimulation ◽  
Visual Cortex ◽  
Receptive Field ◽  
Synaptic Input ◽  
Intracellular Recording ◽  
Cortical Neurons ◽  
Field Studies ◽  
The Other ◽  
Synaptic Potential ◽  
Stimulation Of

AbstractWhen a cortical neuron receives synaptic input from both eyes, do the synaptic pathways that mediate the input from each eye match? In this study, inputs from the two eyes were compared by measuring the latencies of EPSPs and IPSPs evoked by electrical stimulation of the two optic nerves. For binocular neurons, these latencies invariably matched closely, indicating that the pathways from the two eyes contain the same number of synapses; monosynaptic input from lamina A of the lateral geniculate nucleus (LGN) is always matched by monosynaptic input from lamina A1. Conversely, polysynaptic input from one eye, either excitatory or inhibitory, is invariably accompanied by similar input from the other eye. In addition, the match between the two eyes in latency indicates that for each eye a synaptic potential is mediated by the same type of afferent, either X or Y.Judging from intracellular recording, 75% of the neurons studied were binocular, that is, EPSPs could be evoked from either eye. In the remaining 25%, EPSPs could be evoked from only one eye, in agreement with extracellular receptive field studies in which 30% of cortical neurons are monocular.

Face recognition in human extrastriate cortex

1994 ◽  
Vol 71 (2) ◽  
pp. 821-825 ◽  
Author(s):  
T. Allison ◽  
H. Ginter ◽  
G. McCarthy ◽  
A. C. Nobre ◽  
A. Puce ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Face Recognition ◽  
Visual Cortex ◽  
Negative Potential ◽  
The Other ◽  
Extrastriate Cortex ◽  
Extrastriate Visual Cortex ◽  
Left And Right ◽  
Stimulation Of

1. Twenty-four patients with electrodes chronically implanted on the surface of extrastriate visual cortex viewed faces, equiluminant scrambled faces, cars, scrambled cars, and butterflies. 2. A surface-negative potential, N200, was evoked by faces but not by the other categories of stimuli. N200 was recorded only from small regions of the left and right fusiform and inferior temporal gyri. Electrical stimulation of the same region frequently produced a temporary inability to name familiar faces. 3. The results suggest that discrete regions of inferior extrastriate visual cortex, varying in location between individuals, are specialized for the recognition of faces. These "face modules" appear to be intercalated among other functionally specific small regions.

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