Teratogenic effects of mescaline, epinephrine, and norepinephrine in the hamster.

Mescaline was administered orally at doses of 16 and 32 mg/kg on the seventh through tenth days of gestation to pregnant cream-strain hamsters. This treatment resulted in a dose-dependent effect on reproductive success and skeletal ossification. The effect of mescaline on reproductive success included an increased number of resorptions resulting in a decreased litter size. The 32 mg/kg dose of mescaline caused 48.8% resorptions, while 16 mg/kg and control animals had 12.0% and 6.4% resorptions, respectively. Litter size was decreased from 12.0 pups in controls to 10.3 (16 mg/kg) and 6.5 (32 mg/kg) pups per litter in treated groups. No gross abnormalities were observed at necropsy; there was, however, a dose-dependent increased delay in the ossification of the skull, sternum, and metatarsals. Both epinephrine and norepinephrine caused a decrease in reproductive success when administered at 500 micrograms/kg. Epinephrine appeared to cause a trend toward preimplantation wastage as indicated by an increased corpora lutea to implantation site ratio (from 1.3-1.9). Norepinephrine, however, caused an increased number of resorptions (29.1% in controls). Both norepinephrine and epinephrine produced similar delays in ossification.

Response to cryptorchidism of the testis and epididymis of the opossum (Didelphis virginiana).

Adult male opossums, Didelphis virginiana, were rendered hemicryptorchid for 35 days. The cyrptorchid testis exhibited a significant reduction in weight, while the contralateral testis had a compensatory weight gain compared with testes of untreated animals. Histological changes in the cryptorchid testis included fibrosis of the tunica propria, involution of the seminiferous tubules and an apparent increase in the interstitial tissue. Many seminiferous tubules were empty and germinal cells were absent. Some Sertoli cells persisted, but the cytoplasm was vacuolated. Cryptorchid testes were characterized by mononuclear leucocytic invasion around the tubules, and some eosinophils were observed. Cryptorchidism in the opossum may induce a reaction similar to experimental orchitis.

Myelination in chronically-alcoholic mice.

Chronically-administered ethanol, not impaired nutrition, exerts a specific effect to decrease myelination as measured by the activity of the marker enzyme for myelin, 2',3'-cyclic nucleotide 3'-phosphohydrolase.

Behavior and maintenance of the woolly opossum (Caluromys) in captivity.

Circadian activity, general behavior, dietary requirements, and reproductive activity were recorded in a small laboratory colony (four females, six males) of two species of the woolly opossum (Caluromys lanatus and C derbianus) over a period of 3 years. The two species were indiscernable in all aspects of their behavior. Both were completely nocturnal and rarely active during daylight hours. General behavior was apparently related to many variables, particularly individual temperament and cage size. Even docile individuals were more excitable when housed in small cages. Although the woolly opossum is reported to prefer a meat diet, the opossums in this study remained healthy on a meat-egg-fruit diet, and showed a special liking for fruit, especially bananas. Vaginal smears indicated that females of the colony were cyclic, but all attempts to breed them were unsuccessful. Sexual behavior included pre-mount, pelvic-thrust displays on the part of the male, with complete repulsion by all females.