[Disturbance in the function of the spinal centers in diffuse toxic goiter in children (electromyographic study)]. / O narushenii funktsii spinal'nykh tsentrov pri diffuznom toksicheskom zobe u detei (élektromiograficheskoe issledovanie)

Peculiarities of the reflex and motor responses of the soleus muscle were studied in stimulation of the tibial nerve by stimuli of gradually increasing intensity, and also in double stimulation and against the background of contraction of the antagonistic muscles in children with diffuse goiter and in healthy individuals. In sick children an increase and a fall in the H-response amplitude with increase of the stimulation intensity occurred more rapidly than in healthy ones. A rapid restoration of the reflex response at the interval of 500 msec and greater was noted in studying the cycle of restoration of excitation of the motor cells of the anterior horn in sick children. Against the background of contraction of the antagonistic muscles the reciprocal inhibition of the reflex response of the muscle was weaker than in the healthy individuals. The data obtained led to a supposition that one of the causes of motor disturbances in case of an excess of the thyroid hormones in the organism could be a disturbance of the processes of the pre- and postsynaptic inhibition at the spinal level.

[Analysis of the causes of increased tremor in thyroid hyperfuction]. / K analizu prichin usileniia tremora pri giperfunktsii shchitovidnoi zhelezy

The authors present the results of examination of tremor (hand and trunk) of the amplitude of H- and T-reflexes and of the H-reflex inhibition during the contraction of antagonistic muscles and of facilitattion of T- and H-reflexes during the Yendrassik maneuvre in 33 children with hyperfunction of the thyroid gland and 20 normal subjects. It was established that the amplitude of tremor was greater and the frequency was less in these patients than in normal subjects; the amplitude of the H- and T-reflexes was enhanced, and the intensity of reciprocal inhibition of the soleus muscle motor neurons was less in the patients. Comparison of the amplitude of the T- and H-reflexes indicated that against the background of the Yendrassik maneuvre facilitation of the T-reflex was less intense and facilitation of the H-reflex was more intense than in normal subjects. The authors supposed that the enhanced tremor in the patients was due to the motor neurons pool depolarization, to decrease the efficacy of reciprocal inhibition and to diminished suprasegmental influences spread to the gamma-motor neurons.