Human physiology . d, increase of kidney volume from thepassive dilatation of the renal arteries, due to the rise of arterialpressure. The vaso-constrictors of the kidney arise mainly in the dorsaltract of the cord. In the dog the anterior spinal roots from VIII THE EXCKETION OF UEINE 449 the 4th dorsal pair to the 4th lumbar (which correspond with thesecond lumbar pair in man), contain vaso-constrictor fibres for thekidney; but most of them run in the anterior roots of the llth,12th, or 13th thoracic pairs. These vascular fibres, after passingthrough the ganglia of the sympathetic chain,
Human physiology . d, increase of kidney volume from thepassive dilatation of the renal arteries, due to the rise of arterialpressure. The vaso-constrictors of the kidney arise mainly in the dorsaltract of the cord. In the dog the anterior spinal roots from VIII THE EXCKETION OF UEINE 449 the 4th dorsal pair to the 4th lumbar (which correspond with thesecond lumbar pair in man), contain vaso-constrictor fibres for thekidney; but most of them run in the anterior roots of the llth,12th, or 13th thoracic pairs. These vascular fibres, after passingthrough the ganglia of the sympathetic chain, run to the solar plexus,and thence to the renal plexus by the splanchnics, or other the anterior roots of these spinal nerves are excited byrhythmic excitation of low frequency, the result is not constrictionbut active dilatation of the renal arteries, expressed in a swellingof the kidney. This fact, discovered by Bradford, shows thatthese roots contain vaso-dilator fibres to the renal arteries, besides. FIG. 120.—Increase of arterial pressure (P), and decrease in kidney volume (V), due to asphyxiacommencing at A. (J. Cohnheim and C. Roy.) the vaso-constrictors. The former are excited by rapid rhythmicalstimulation, the latter by a slow rhythm. Both kinds of vascularfibres seem to follow the same path till they penetrate into thekidney. It is still doubtful whether the spinal fibres from one sideinnervate only the vessels of the kidney on the same side, orpartly those on the opposite side as well. It is also doubtfulwhether the vagus contains fibres to the kidney. Certain experi-ments carried out in Belgium by Masius (1888), in France byArthaud and Butte (1890), and repeated in Italy by Vanni(1893), seemed to show that the vagi may exert a direct vasornotoraction on the kidneys, independent of the action of thesenerves on the heart and on arterial pressure. But this interpreta-tion is excluded by the subsequent work of Walraweus (1896)in Albertonis laboratory
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectphysiology, bookyear1
