The chemical composition of the vitreous humor of animal eyes.

Abstract

A survey of the literature revealed but incomplete data on the chemical composition of the vitreous humor. It was therefore deemed advisable to determine in this body fluid the concentration of some of the compounds known to occur in the blood and cerebrospinal fluid. This work represents a preliminary step in the study of the humors of normal and pathological human eyes. The use of the microchemical methods has made possible the more extensive analysis of the vitreous humors of individual eyes.

Analyses were made of the vitreous humors of the eyes of oxen, horses and pigs. The eyes were removed, without trauma, from the animals immediately after slaughter. The aqueous humor was withdrawn by a syringe, and the entire vitreous shelled out through an incision in the sclera of the posterior part of the eyeball. After rupturing the membrane, the vitreous was poured upon a C. S. and S. filter paper No. 595, and covered with a watch glass. The filtrate was taken for analysis. All material analysed was fresh. Not more than 45 minutes elapsed between the death of the animal and the beginning of the analysis. The oxen and pigs were young animals, but the horses ranged from 12 to 20 years. The horses were killed instantaneously by a shot into the brain. All animals were free from disease.

The analytical studies included determinations of total solids, specific gravity, proteins, non-protein nitrogenous compounds, chlorides, sugar, phosphorus, sulphur, potassium, sodium, calcium, lactic acid and the ether soluble fraction. All results are reported in terms of mg. of these components to 100 cc. of the filtrable portion of the vitreous. The figures reported in the table are averages of from 6 to 12 determinations.