Date of Award


Document Type


Degree Name

Master of Science (MS)




The purpose of this study was to determine what histological parameters of the rat's spleen were altered as a result of the anesthetic agent used. It also was desired to determine which anesthetic agent might be the most suitable to use in a transillumination study of the microcirculation of the living rat's spleen.

It was found that sodium Amytal administered intraperitoneally results in splenic dilatation. Chloral hydrate and sodium thiopental, given intraperitoneally, resulted in splenic contraction. Penthrane, ether, and chloroform administered by inhalation technique also resulted in splenic contraction. Penthrane and chloral hydrate while producing splenic contraction appear to do so to a lesser extent than the other contracting anesthetic used.

In the contracted spleen the organ decreased in size, especially in length; the capsule was thicker and the red pulp sinuses were smaller in diameter. It was also noted that the ratio of the white pulp nodule in respect to the marginal zone varied with contraction and dilatation of the spleen. In the contracted spleen the marginal zone decreased in size and in the number of erythrocytes found within the zone. In the dilatated spleen the marginal zone increased in size with respect to the white pulp nodule, and the marginal zone appeared flooded with erythrocytes.

To investigate the microcirculation through the marginal zone sodium Amytal appears to be the best anesthetic because it was during the use of this anesthetic that the marginal zone was richly supplied with erythrocytes.

It is apparent that to determine the entire microcirculation of the spleen one must also use an anesthetic that will produce splenic contraction and of those tested Pentothal should be satisfactory.