Herman Zaiman

THE DEVELOPMENT OF LYSOSOMES IN RAT SKELETAL MUSCLE IN TRICHINOUS MYOSITIS

Rat striated muscle (gastroenemius) containing encysted Trichinella larvae was studied histochemically for hydrolases associated with lysosomes. Activity of the enzymes studied (acid phosphatase, esterase, aminopeptidase), not demonstrable in appreciable amounts in normal striated muscle, appears in the altered muscle fibers in granules which by various criteria are demonstrated to be lysosomes. The increase in lysosomal enzyme activity is accompanied by increased prominence of the Golgi apparatus, as demonstrated by thiamine pyrophosphatase activity, and by an increase in the ribonucleoprotein content of the muscle fibers. These changes illustrate the facultative development of lysosomes and their associated ferments during a regenerative process. They suggest the need for a revision of the classic concept of the primarily degenerative nature of the trichinous lesion as well as a possible role of the developing lysosomes in this process.

Mortality and Survival of Young Male Mice given Single Massive Doses of Trichinella spiralis Larvae.

Abstract Three hundred thirty-three 5-week-old male Swiss albino mice divided into 11 equal groups in four experiments were inoculated with single graded doses of Trichinella spiralis larvae. Doses ranged from 400 to 51,200 larvae per mouse. Within the limits of these experiments, (1) the number of deaths among mice infected with increasing numbers of larvae increased until a mortality of one hundred per cent (100%) was reached. (2) Mean and median survival times varied inversely with the size of the inoculum. (3) There was no assurance that mean survival times for groups of homogeneous mice inoculated with equal dosages in different experiments would be comparable or precisely predictable.

ELECTROCARDIOGRAPHIC CHANGES OCCURRING IN TRICHINELLA- INFECTED RATS PRIOR TO LARVIPOSITION AND MIGRATION.

Abstract Two experiments were designed to determine the onset, duration, and some of the characteristics of electrocardiographic changes in rats infected with known numbers of Trichinella spiralis larvae. Prolongation of the T wave occurred as early as the first day after infection, at a time which antidates larviposition and migration of second generation larvae. The T wave change persisted at least 47 days. The abnormality was no longer present on day 75 after infection.

Mortality and survival times of trichinized mice treated with cortisone acetate.

Abstract Young male mice inoculated per os with 6,400 Trichinella spiralis larvae were subsequently given single intraperitoneal injections of either water, 90% sucrose, or cortisone acetate at two dosage rates, namely, 25 and 2.5 mg/kg body weight. The average survival time of the cortisone treated animals was 42.5 hours for the larger dose and 50.4 hours for the lesser dose. Survival of animals injected with water or sugar averaged 71.8 hours. Similar mice inoculated with 3,200 or 1,600 larvae were injected twice weekly with water or cortisone acetate (25 or 2.5 mg/kg of body weight) for a period of 5 weeks. All mice receiving the higher doses of cortisone perished. Mice treated with water died somewhat more slowly than did the cortisone treated animals and in fewer numbers if inoculated with 1,600 larvae.

Eosinophilia in rats infected with Trichinella spiralis

Abstract Infection of young adult male Holtzman rats with 4,000 Trichinella spiralis larvae initiated a moderate leucocytosis as early as the first post-infection day. This elevation of the white cell count was observed in 9 of the 10 post-infection days studied. A rise in circulating eosinophiles which was first noted on the fifth post-infection day persisted through post-infection days 6, 7, 8, 9 and 10. The rise in eosinophiles was statistically significant on days 5, 6, 8, 9 and 10.

Mortality of Young Male Mice infected with 6,400 Normal or Irradiated Trichinella spiralis Larvae.

Abstract Each of a total of 106 five-week-old male Swiss albino mice divided into four groups, was inoculated with 6,400 Trichinella spiralis larvae subjected to various doses of roentgen radiation and their survival times recorded. One hundred per cent of the mice died if the larvae received no irradiation. None died if the larvae received 12,000 r. Approximately 85% of the mice died if the larvae were irradiated with 8,000 or 10,000 r.

SURVIVAL TIME OF TRICHINIZED MICE TREATED WITH CORTISONE ACETATE, ACTH, SUGAR SOLUTIONS, OR WATER.

Abstract Each of 246 5-week-old male mice divided into 8 groups was inoculated with 6400 Trichinella spiralis larvae and subsequently with intraperitoneal injections of either cortisone acetate, ACTH, distilled water, or sugar solution in varying dosages. All of the animals died. With one exception [the median death time of those mice receiving the lowest amount of ACTH (Group VI)], the mean and median survival times of cortisone- or ACTH-treated animals were less than those for water- or sugar-treated controls. Mean survival times of the mice were significantly shortened by injection with the larger doses of ACTH and cortisone. Nothing in the data suggested that ACTH or cortisone was beneficial to heavily trichinized mice.

Experimental Trichinous Myocarditis in Parabiotic Animals.

Infection of one member of a pair of parabiotic rats with various numbers of Trichinella spiralis larvae consistently produced myocarditis in the infected rat. No myocarditis was seen in any of the “uninfected parabionts”.