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We measured tightly bound nuclear estrogen receptors (ER) in sex skin biopsies obtained from pig-tailed macaques (Macaca nemestrina) which were previously ovariectomized and treated with an estradiol-progesterone regimen. Incubation of fresh tissue slices with a saturating concentration of [3H]estradiol (E2) was done to determine the capacity of nuclear acceptor sites to bind activated ER with high affinity. The radiolabeled ER was extracted from nuclei with 0.5 M KCl, complexed with an anti-ER monoclonal antibody, and quantitated by analysis on sucrose gradients. Even though serum E2 levels were unchanged, 7 and 14 days of sequential progesterone (P) treatment decreased ER amounts below those found after 7, 14 and 21-23 days of E2 treatment. ER regulation in sex skin of this species is similar to that found in macaque reproductive tract; P suppresses ER levels even in the presence of continuous E2. The tissue responses of sex skin to the hormone treatments correlated well with the measured fluctuations of tightly bound nuclear ER, which suggests the functional significance of this ER component.

We sampled the reproductive tracts of 27 cynomolgus macaques during the menstrual cycle and correlated the cytologic changes in the oviductal epithelium with changes in the serum levels of estradiol (E2) and progesterone (P) and with the histology of the ovaries and the endometria. We identified an orderly sequence of changes in the oviductal epithelium from the early follicular to the late luteal phase, and we classified this sequence into eight stages, named as follows: preciliogenic, ciliogenic, ciliogenic-ciliated, ciliated-ciliogenic, ciliated-secretory, early regression, late regression and full regression. The preciliogenic and ciliogenic phases were coincident with menses and the early follicular phase. The ciliogenic-ciliated, ciliated-ciliogenic and ciliated-secretory phases during which the oviductal epithelium became progressively more differentiated were coincident, respectively, with the midfollicular, late follicular and periovulatory phases of the cycle. The early, late and full regression stages during which the epithelium became progressively more atrophied, deciliated and nonsecretory were coincident, respectively, with the early, mid and late luteal phases of the cycle. The cyclic changes in the endometrium of cynomolgus macaques were similar to those reported for the rhesus macaque.

Young human dermis is charterized by the presence of many fibroblasts with distended endoplasmic reticulum, extensive Golgi bodies, and orderly and "clean"-appearing groundwork. Older dermis contains inactive fibrocytes with lipofuscin-like granules, macrophages with dense granules, and extracellular spaces with evidence of degeneration. We have found the sex skin of cycling pigtail macaques (Macaca nemestrina) a predictable model for studies on aging changes in human dermis. Swollen sex skin has many biochemical and ultrastructural properties that are similar to those of young dermis, and deflated sex skin resembles older human skin. Sex skin, however, is unique in that it becomes "rejuvenated" with each succeeding ovarian cycle. This animal model may prove useful to researchers attempting to increase their understanding of aging in connective tissue.

Glycosaminoglycan (GAG) infiltration of the skin is a feature of hyperthyroidism, hypothyroidism, pretibial myxedema, scleromyxedema, and scleredema. We investigated the pathogenesis of the GAG deposits using light microscopy, histochemical digestion with a series of GAG-specific enzymes, and electron microscopy. Hyaluronic acid was the main GAG in all the conditions and in normal skin. Furthermore, there was minimal histologic variability of GAG dermal distribution. A striking distinguishing feature involved dermal fibroblast activity, which appeared normal or inactive in thyroid disorders and hypertrophic and/or hyperplastic in scleromyxedema and scleredema. Thus, the acquired cutaneous mucinoses exhibit similar skin GAG distribution and biochemical composition. The morphologic differences in fibroblastic activity suggest that the mucinoses of scleredema and scleromyxedema represent a local process, whereas the GAG infiltration of thyroid diseases may have a systemic origin.

Sequential steroid administration of estradiol (E2) and progesterone (P) in spayed pigtailed macaques was used to precisely control the time course of sex skin swelling. After removal of the P implant, the sex skin swelled considerably and the water content of the sex skin increased manyfold over that of back skin. During the swelling phase, hyaluronate biosynthesis in sex skin increased dramatically compared with back skin of the same animals. Collagen synthesis also increased but to a lesser extent. Estrogen receptor levels were undetectable in back skin and very low in spayed animals that had been treated with both E2 and P. After removal of the P implant, both the level of estrogen receptor and the rate of hyaluronate biosynthesis increased. Immunocytochemistry with monoclonal antibodies against the estrogen receptor showed that the dermal fibroblast was the only cell type to stain positively for estrogen receptor. We conclude that the sex skin swelling that follows P withdrawal in pigtailed macaques bearing E2 implants is mediated by estrogen receptors in dermal fibroblasts and is a result of increased hyaluronic acid synthesis by these cells.

In vitro frog gastric mucosa was employed as a model for a combined physiological, biochemical, and ultrastructural study of the morphological changes which accompany the onset of acid secretion by the oxyntic cell. The histamine H2-receptor antagonist metiamide was used to provide a reproducible control state. Stimulation of acid production by theophylline resulted in a 10-fold increase in plasma membrane surface area and a distinct change in the conformation of mitochondrial cristae. Studies using the acid secretion inhibitors, thiocyanate and anoxia, demonstrated that neither acid production per se nor oxidative metabolism is essential for the theophylline-dependent changes in surface area. Increases in tissue cyclic AMP levels were observed under the conditions producing morphological changes. It is postulated that surface area changes induced by theophylline are controlled by cellular cyclic AMP levels.

The involvement of de novo protein synthesis in acid secretion by the in vitro bullfrog gastric mucosa was examined using the inhibitors cycloheximide and puromycin. Both inhibitors reduced [3H]leucine incorporation by more than 90%. The inhibition of protein synthesis had no influence on spontaneous acid secretion nor did it effect secretory stimulation by histamine, carbachol, pentagastrin, or theophylline. Oxygen consumption by nonstimulated and theophyllinestimulated tissues was shown to be independent of protein synthesis. The dramatic morphological changes observed in oxyntic cells during a transition from rest to active secretion persisted in cycloheximide-and puromycin-treated tissues. Stereological analysis of the apical membrane surface area density failed to demonstrate any quantitative influence of protein synthesis inhibition. These studies quantitatively confirm that protein synthesis is not required for the biochemical and morphological events involved in acid secretion by the in vitro frog gastric mucosa.

We have used GMA-embedded tissues sectioned 2-3 mu for the identification of granulated cells in wounded and normal macaque tissues. Mast cell granules stain brilliantly with Giemsa or with PAS counterstained with alcian blue, neutrophils stand out clearly when treated with the PAS method and macrophage granules stain with PAS as well as with basic dyes. These techniques are helpful for the identification of these cells during wound healing and during inflammatory processes.