The Effects of Peripheral Inhibition on the Muscle Action Potentials of the Crab

1941 ◽  
Vol 14 (3) ◽  
pp. 296-304 ◽  
Author(s):  
C. A. G. Wiersma ◽  
R. G. Helfer
Keyword(s):  
Action Potentials ◽  
Muscle Action ◽  
Peripheral Inhibition

scholarly journals A Comparative Study of Peripheral Inhibition in Decapod Crustaceans

1942 ◽  
Vol 18 (3) ◽  
pp. 223-236
Author(s):  
C. A. G. WIERSMA ◽  
C. H. ELLIS
Keyword(s):  
Action Potentials ◽  
Mechanical Response ◽  
No Reduction ◽  
Single Stimulus ◽  
Muscle Action ◽  
Decapod Crustaceans ◽  
High Frequencies ◽  
Muscle Action Potential ◽  
Wide Range ◽  
Peripheral Inhibition

The effectiveness with which different contractions in a number of muscles can be inhibited was investigated. As a measure of this effectiveness the frequency of inhibition which can just inhibit a contraction with a given frequency of excitation was determined. It was found that in all systems the ratio (Rc) of such inhibitory frequencies to that of the excitatory frequencies they can suppress was constant for a wide range of frequencies. At high frequencies either the inhibition or the excitation may become less effective. This is explained by failure of the respective system to function normally at such a frequency. The effectiveness of inhibition of different systems was determined. Some systems show a very constant Rc value; in a second group Rc varies within wider limits; and a third group shows two distinct Rc's sometimes in the same preparation at different times. Rc values have been found to vary widely. For instance, in the bender inhibitor-slow bender system of Pachygrapsus three excitatory impulses are suppressed by one inhibitory impulse; in the closer inhibitor-slow closer system of Cambarus one excitatory impulse needs five inhibitory impulses to counteract its effect. The fast closer contraction of Cambarus and the fast closer and fast bender contraction of Pachygrapsus were found to be uninhibitable, i.e. no effect of inhibition whatsoever was noticed on any of these contractions. All three systems are distinguished by giving a mechanical response to a single stimulus in contrast with all the inhibitable systems which do not respond to single impulses. Reduction of the action potentials during inhibition is obtainable in only a few systems, namely, the opener inhibitor-opener and the stretcher inhibitor-stretcher systems of Cambarus and the crabs. (In the crabs this applies only to the ‘true’ inhibitors.) In all other systems, including every system of Panulirus, no reduction of the muscle action potential is obtained.

Latency of compound muscle action potentials of the anal sphincter after magnetic sacral stimulation

2001 ◽  
Vol 24 (9) ◽  
pp. 1232-1235 ◽  
Author(s):  
G.L. Morren ◽  
S. Walter ◽  
H. Lindehammar ◽  
O. Hallböök ◽  
R. Sjödahl
Keyword(s):  
Anal Sphincter ◽  
Action Potentials ◽  
Muscle Action ◽  
Compound Muscle Action Potentials ◽  
Sacral Stimulation

Mapping the Compound Muscle Action Potentials of Cricothyroid Muscle Using Electromyography in Thyroid Operations

2009 ◽  
Vol 250 (2) ◽  
pp. 293-300 ◽  
Author(s):  
Ben Selvan ◽  
Srinivasa Babu ◽  
M J. Paul ◽  
Deepak Abraham ◽  
Prasanna Samuel ◽  
...  
Keyword(s):  
Action Potentials ◽  
Muscle Action ◽  
Cricothyroid Muscle ◽  
Compound Muscle Action Potentials

Variations in Skin Resistance and Their Relationship to G.S.R. Conditioning

1960 ◽  
Vol 106 (442) ◽  
pp. 281-287 ◽  
Author(s):  
Irene Martin
Keyword(s):  
Action Potentials ◽  
Background Activity ◽  
Skin Resistance ◽  
Muscle Action ◽  
Muscle Tonus ◽  
Experimental Procedure ◽  
Discontinuous Nature ◽  
The Subject ◽  
Neural Excitation ◽  
Set Up

Any particular system which is being conditioned is likely to maintain a certain level of background activity throughout the experimental procedure; either of a discontinuous nature, as, for example, with eyeblink, heart rate and respiratory cycle, or continuously, as in the case of basal skin resistance and muscle tonus. This background activity or level of arousal does not remain constant but usually varies in time, presumably as a result of underlying neural excitation or inhibition. It may increase throughout an experiment if the subject becomes highly motivated, as with the gradients of muscle action potentials observed by Bartoshuk (1955), or decrease, if the subject becomes more relaxed and familiar with the set-up, as Duffy and Lacey (1946) found with level of skin conductance.

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