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Updated: Aug 14, 2026

Measures of Heart and Ventilatory Rates in Freely Moving Crayfish
Published on: October 15, 2009
[The metasympathetic mechanisms supporting the constancy and stability of the internal environment in vertebrates]
Abstract:
The data were obtained with the aid of extracellular recording of unit activity in the cardial, enteral and respiratory parts of the metasympathetic nervous system, staining of the neural tissue preparations of atrial walls, intestine and lower part of the guinea pig trachea. The neurons were shown to be very sensitive to the main homeostatic contants: pH of the perfusion solution, its temperature and the grade of oxygenation. These structures were shown to take a direct part in maintenance of the constancy and stability of the organism inner milieu. Sympathetic nervous system differs from the above system in that the former is the system of transmission, defence, mobilisation of resources which is necessary for active interaction of the organism with ambient milieu.
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