Section I:

In order to determine the effects of propylthiouracil-induced hypothyroidism on the Formosan strain of Schistosoma japonicum in mice, one group of mice (NON-PTU) was maintained on Purina Lab Chow meal only; the other group of mice (PTU) was fed a goiterogenic diet of 0.2% propylthiouracil in Purina Lab Chow meal. The mice in both groups were percutaneously exposed to 60 to 72 cercariae. The mice were perfused for schistosomes after an infection period of two months. It was found that the number of worms recovered was not significantly different between the two groups of mice. PTU mice weighed significantly less than NON-PTU mice; the greater the intensity of infection (measured by the great number of adult female worms present per mouse), the lesser the mouse weight. Adult worms from hypothyroid mice were significantly shorter than adult worms from non-hypothyroid mice. There was a greater proportion of adult male worms with unusual location of testes from hypothyroid mice as compared to male worms from non-hypothyroid mice. Except for the spleen of hypothyroid mice which had a higher percentage of schistosome eggs, no differences were noted in the mean percentages of schistosome egg distributions in the visceral organs between the two group of mice.

Section II:

The study evaluates 1) the tolerance of antimony potassium tartrate (APT) in normal and hypothyroid, uninfected mice, and 2) the antischistosomal effects of APT in infected normal and infected hypothyroid mice. Part I. Tolerance of normal vs. hypothyroid mice to different dosages of APT: 35, 42, 48, 54, and 60 mg/kg wt. Additionally, 66 and 72 mg were given to hypothyroid mice only. The hypothyroid mice were able to tolerate higher dosages of APT (by 31%), and the LD50 was increased from 43.6 mg to 57.0 mg APT/kg wt. Part II. Antischistosomal effects of APT on normal vs. hypothyroid mice. The mice infected with 60 to 72 cercariae of Schistosoma japonicum. In Group II A, an equal number of normal and hypothyroid mice were treated with 35 mg APT/kg wt on day 24 post infection. More (24.3%) hypothyroid mice were positive for schistosomes following treatment with 35 mg APT/kg wt than were the normal infected mice (8.6%) receiving the same dosage of APT. In Group II B half the normal nice were treated with 35 mg APT/kg wt and half the hypothyroid mice were given 45 mg APT/kg wt. The efficacy of the drug for normal mice given 35 mg APT/kg wt was comparable to the hypothyroid mice which received 45 mg APT/kg wt. It is concluded that PTU-induced hypothyroidism increases the tolerance of mice to APT, but it diminishes the schistosomicidal effect of the drug.

LLU Discipline





Graduate School

First Advisor

Edward D. Wagner

Second Advisor

Ian M. Fraser

Third Advisor

Ariel A. Roth

Fourth Advisor

Raymond E. Ryckman

Fifth Advisor

Earl W. Lathrop

Sixth Advisor

Leonard R. Brand

Degree Name

Doctor of Philosophy (PhD)

Degree Level


Year Degree Awarded


Date (Title Page)




Library of Congress/MESH Subject Headings

Schistosoma japonicum; Hyperthyroidism



Page Count

vii; 37

Digital Format


Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

Collection Website



Loma Linda University. Del E. Webb Memorial Library. University Archives