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.

HIGH-FREQUENCY MONOPOLAR ELECTRICAL STIMULATION OF THE RAT CEREBRAL CORTEX

Neurosurgery ◽  
2007 ◽  
Vol 60 (1) ◽  
pp. 189-197 ◽  
Author(s):  
Masahiro Oinuma ◽  
Kyouichi Suzuki ◽  
Takashi Honda ◽  
Masato Matsumoto ◽  
Tatsuya Sasaki ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Electrical Stimulation ◽  
High Frequency ◽  
Rat Cerebral Cortex ◽  
Stimulation Of

THE EFFECT OF TEMPERATURE ON THE EXPRESSION OF FACTORS GOVERNING RUST REACTION IN A CROSS BETWEEN TWO VARIETIES OF TRITICUM VULGARE

1931 ◽  
Vol 5 (2) ◽  
pp. 200-207 ◽  
Author(s):  
J. B. Harrington
Keyword(s):  
Low Temperature ◽  
Genetic Factors ◽  
The Other ◽  
Effect Of Temperature ◽  
Puccinia Graminis ◽  
Genetic Studies ◽  
Triticum Vulgare ◽  
Susceptibility Factors ◽  
Different Temperatures ◽  
Genetic Hypothesis

Two random populations of F2 plants of the cross Marquillo × Marquis were tested for the reaction of their F3 seedling progenies to form 21 of Puccinia graminis tritici in the greenhouse, at average daily temperatures of 69.7° F. (the warm test) for one population, and 60.6° F. (the cool test) for the other. In both tests Marquis was susceptible and Marquillo was resistant. In the "warm test" ten families of a total of 781 were resistant. In the "cool test" five families of a total of 301 were susceptible. In both cases the results fitted a 63:1 ratio excellently, indicating the operation of three main genetic factors for rust reaction. A genetic hypothesis is proposed that explains the results on the basis of the influence of low temperature in curtailing the action of three susceptibility factors A, B and C carried by Marquis. The results indicate that genetic studies on characters which are easily influenced by environmental conditions should be made under controlled conditions, after ascertaining in advance the general effects of different temperatures, etc., upon the hybrid material to be used.

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.

RHIZOPUS ROOT ROT OF SUGAR BEET

1943 ◽  
Vol 21c (8) ◽  
pp. 235-248 ◽  
Author(s):  
A. A. Hildebrand ◽  
L. W. Koch
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Sugar Beet ◽  
Root Rot ◽  
The Other ◽  
Effect Of Temperature ◽  
Experimental Plot ◽  
Optimum Growth ◽  
Causal Organism ◽  
Sugar Beets

During the summer of 1942 sugar beets growing in an experimental plot at the Harrow laboratory were destroyed by a root rot of a type that apparently has been reported only once previously on this host in North America. Wilting of the foliage first attracts attention to affected plants, the roots of which show, externally, grayish-brown discoloured areas and, internally, fairly sharply-delimited, grayish to coffee-coloured lesions, affected tissues being more or less spongy in consistency. The causal organism, found to be a wound parasite, has been identified as Rhizopus arrhizus Fischer. The effect of temperature on the growth in culture and on the pathogenicity of this fungus and of representatives of the species, R. oryzae and R. nigricans, has been studied. It has been found that R. arrhizus and R. oryzae are relatively high temperature organisms, showing optimum growth at about 34° to 36 °C., and each capable of infecting and destroying artificially injured sugar beets most rapidly between 30° and 40 °C. R. nigricans, also a wound parasite is, on the other hand, a relatively low temperature organism showing optimum growth in culture at about 24° and displaying highest infection capability at about 14° to 16 °C.

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