(1) Action upon the Liver.
Whether we are dealing with the venoms of Viperidæ or Colubridæ, the anatomo-pathological processes are alike, and the changes produced are more or less profound, according to the degree or the slowness of the intoxication.
The liver is more affected than any other organ. In cases in which death has quickly followed the injection of the venom, the protoplasm of the cells is merely cloudy, or granular, and the granulations readily take a stain in their periphery, though the interior remains uncoloured. If, on the contrary, the animal has survived for some hours, the protoplasm becomes condensed in certain parts of the cell, leaving vacuoles, the limits of which are not well defined. A portion of the cellular protoplasm is necrosed and destroyed. In these cases the nuclei have already undergone a change; although their contours may be well defined, we discover in their interior only a very little chromatin in the form of small granulations, and the nuclear fluid takes a feeble stain with basic colours, since it contains a little chromatin in solution.
When the protoplasm of the hepatic cells has suffered more pronounced lesions, the changes in the nuclei are also more marked; the quantity of nuclear chromatin diminishes and slowly loses its property of taking stains, in proportion as the protoplasm of the hepatic cells undergoes necrosis; finally, in the hepatic cell, there remains nothing more than a small quantity of granular protoplasm without a nucleus (Nowak).
In certain cases we find extensive areas of fatty degeneration, or small foci in which the hepatic tissue is absolutely destroyed. In the case of the dog it may even happen that the microscopic structure of the parenchyma has entirely disappeared. The arrangement of the hepatic cells in lobules can no longer be distinguished; the trabeculæ are ruptured and broken asunder, and we find nothing more than a confused agglomeration of cells floating in the extravasated blood.
In animals which have lived for a long time after being poisoned, lesions of the bile-ducts are also found. The epithelial cells have undergone fatty degeneration, or else, in the case of small animals, the ducts appear infiltrated with small mononuclear cells, which penetrate between the epithelial cells of the canaliculi. Sometimes also the latter cells are distended, and enclose large vacuoles.
Venom thus produces in the liver lesions of fatty degeneration, or necrosis, and an infiltration of the bile-ducts by lymphatic cells.
(2) Action upon the Kidney.
The changes in the kidney are also very extensive. The three portions of the glomerulus often exhibit lesions; the vessels of the tuft show ectasia; their walls are sometimes ruptured, and the blood is extravasated into the capsular cavity. The latter is filled with a granular exudation, which varies in amount with the slowness of the intoxication. The epithelial lining of Bowman’s capsule is swollen; the nucleus stains badly (Vaillant-Hovius).
In the tubuli contorti the lesions in the cells greatly resemble those seen in the liver. Granulations and vacuoles appear, and the nucleus becomes diffuse. The lumens of the tubules are filled with necrosed cells, and the branches of Henle are found to be similarly obliterated.