The heart of metamorphosing Mexican axolotl but not that of the cardiac mutant is associated with the upregulation of Hox A5.

The Mexican axolotl (Ambystoma mexicanum) is a facultative neotene which rarely undergoes metamorphosis in the wild. We now report for the first time a dramatic increase in the expression of HoxA5 in axolotl hearts as determined by RT-PCR and in situ hybridization analyses during spontaneous metamorphosis. The Mexican axolotl has a naturally occurring mutation called gene c which allows hearts in homozygous (c/c) embryos to form but never to beat.

Immunocytochemical localization of insulin- and somatostatin-like material in human breast tumors.

Four types of human breast lesions and C3H mouse mammary adenocarcinomas (type A) were examined for the immunocytochemical localization of cells containing hormone-like substances. Insulin- or somatostatin-like immunoreactive material was observed in scattered single cells and nests of tumor cells in seven of eight infiltrating duct carcinomas, and in the majority of tumor cells from an anaplastic carcinoma. A few somatostatin-immunoreactive cells were observed in only one of seven fibroadenomas studied.

Changes in uterine morphology which accompany the development of preneoplastic and neoplastic mammary lesions in old mice.

Because of the accumulating evidence that anatomical and physiological changes occur in sites and systems removed from primary tumors, uterine morphology during the development of mammary tumors in C3H/HeJ mice was investigated. C3H/HeJ mice contain the mouse mammary tumor (MTV) virus in their milk and have a high incidence of mammary tumorigenesis. The C3HeB/FeJ mice, used as one set of controls, do not contain the mouse MTV virus in their milk and have a low incidence of mammary tumorigenesis.

Fine structure analysis and surface characteristics of mouse mammary gland adenocarcinomas.

Mammary adenocarcinomas from C3H/HeJ mice carrying the mammary tumor virus were studied by means of light, transmission, and scanning electron microscopy. The histological appearance of the tumors was variable; however, 60% were classified as type B adenocarcinomas, while 20% were type A and 20% were composed of equal regions characteristic of both types. Four populations of tumor cells were observed with the TEM.

Immunoreactive hormones in human breast tissues.

Samples of breast tissue obtained at biopsy or mastectomy from women with benign breast disease and infiltrating duct or anaplastic carcinoma were maintained for 2 weeks in organ culture synthetic medium 199 without additional serum or hormones. Media were changed every 48 hours. Media withdrawn from the tissues were assayed for insulin, prolactin (Prl), and parathyroid hormone (PTH).

Male mouse accessory sex glands in organ culture.

Explants of epididymis, vas deferens, seminal vesicle, and coagulating gland from 10-12-week-old and 7-8-month-old male Swiss Webster mice were maintained in synthetic media without serum or hormones for up to 28 days. Differences were observed in the survival and responses of each gland and the behavior of the principal and basal cells. Epithelial cell migration was pronounced in the vas, moderate in the epididymis, and low in the seminal and coagulating gland.

Effects of perphenazine and bromocriptine on male accessory sex glands. III. The prostate gland.

The in vivo morphologic effects of androgen, perphenazine (a prolactin release stimulator), and bromocriptine (a prolactin release inhibitor) on the ventral prostate glands of immature intact and castrate C3H/HeJ mice were studied. Normal prostatic stromal and epithelial development was controlled by testicular androgens. Stromal proliferation and epithelial degeneration followed prepubertal castration at 21 d of age.

Effects of bromocriptine and perphenazine on male accessory sex glands II. Ultrastructure of the seminal vesicles.

The effects of prolactin (PRL) and androgen on the seminal vesicles of immature C3H/HeJ mice were studied. Glands from controls exhibited secretory activity and full differentiation. Glands from castrates were small, markedly atrophic with some stromal hyperplasia and moderate leukocytic infiltration.

Effects of bromocriptine and perphenazine on male accessory sex glands. I. The seminal vesicles.

The effects of bromocriptine and perphenazine on C3H/HeJ mouse seminal vesicles were studied. The response of the stroma and parenchyma of the glands to the hormones differed. Testosterone repressed stromal proliferation.

Morphological changes in the mammalian vas deferens during aging. I. The occurrence of binuclear cells in the mouse.

The number of nuclei per principal cell was determined in the vas deferens of sexually immature, young sexually mature and old male mice. The incidence of binucleation increased with age. In 21-day-old mice approximately 99% of the principal cells were mononucleated and 9%-20% of the principal cells were binucleated.

The effect of oxandrolone on low and high density lipoprotein profiles in retired breeder rats.

The retired breeder rat, an animal known to undergo premature aging and to develop hypercholesterolemia, was studied to determine the effect of oxandrolone, a synthetic hypolipidemic steroid, on serum lipoprotein subfractions. The methods utilized for this study included density ultracentrifugation, electron microscopic lipoprotein particle sizing, and disc gel electrophoresis. The data confirmed the cholesterol-lowering ability of oxandrolone and demonstrated that its effect on total serum cholesterol was limited to the low and high density lipoprotein subclasses.

Cell surface differences in ducts from cancerous and noncancerous human breasts.

The scanning electron microscope reveals structural differences between the apical microvilli of duct cells from cancerous and noncancerous human breasts. The alterations in the microvilli from carcinomatous breasts appear to be highly specific, to extend throughout the affected breast, and may be pathognomonic for this condition.