頸部交感神経刺激の甲状腺ホルモン分泌機構に及ぼす影響
1959 年 34 巻 10 号 p. 978-998,933
詳細
1959 年 34 巻 10 号 p. 978-998,933
In order to investigate whether the autonomic innervation of the thyroid gland modifies the functional activity of this organ or not, the author studied the influence of the electrical stimulation of the cervical sympathetic nerve on the content of PBI131 in thyroidal venous blood in the dogs into which tracer dosis of I131 had been injected intravenously 5 or 6 days before experiment.
The following results were obtained :
1. After the stimulation of the right cranial cervical sympathetic ganglion, the concentration of PBI131 in thyroidal venous blood increased in 5 of 6 cases 2.1 to 7.61 times of the pre-stimulation level and the PBI131 output increased in 4 of 6 cases 1.47 to 3.52 times of the pre-stimulation level. In spite of the stimulation of the unilateral sympathetic nerve, the increase was observed bilaterally and no difference in particular between both sides. No significant influence was seen about the thyroidal venous blood flow by the stimulation.
2. Following the stimulation of the ansa subclavia of the right sympathetic nerve, the concentration of PBI131 increased in 4 of 10 cases 1.72 to 2.22 times of the pre-stimulation level and the PBI131 output increased 2.5 times of the pre-stimulation level in one of 6 cases. In the remaining 4 cases the exact output could not be calculated because of the reduced thyroidal venous blood flow. Such increases were observed bilaterally and no difference in particular between both sides. No significant influence was seen about the blood flow through the thyroid gland by the stimulation.
3. In hypophysectomized dogs with transplanted pituitary on their back, the concentration of PBI131 increased in 2 of 4 cases 1.75 to 2.9 times of the pre-stimulation level and the PBI131 output increased in 3 of 4 cases 1.61 to 1.91 times of the pre-stimulation level, following the stimulation of the right cranial cervical sympathetic ganglion. Such increases were observed only in the stimulated side.
4. The results from these experiments indicate that the mechanism of the hormonal secretion of the thyroid gland can be modified by the cervical sympathetic nerves, mainly by fibers passing through the cranial cervical ganglion and occasionally by those passing through the caudal cervical ganglion or the stellate in part. It seems likely that the unilateral cervical sympathetic nerve can modify the functional activity of the thyroid gland bilaterally and that such a nervous control is rather secretomotoric than vasomotoric.
