摘要:

The study of adult rat anterior pituitary maintained in vitro was made possible by a modification of the suspension system used in the watch-glass method of organ culture. The integrity and health of the tissue was observed with the electron microscope. Somatotrophs and gonadotrophs were seen routinely. A cell with large (400–750 nm) granules and thought to be a luteotroph (mammotroph) was also seen. These results support the use of this method for the growth of adult rat anterior pituitary, or other large explants, for short periods of time in organ cultur

ISSN:1422-6405    

DOI:10.1159/000145416

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

Acetylcholinesterase, butyrylcholinesterase and monoamine oxidase activities were observed in the neuronal and non-neuronal components of the preputial gland. Histological, histochemical and experimental studies clearly indicate that the preputial gland of the rat is innervated by cholinergic as well as adrenergic nerves.

ISSN:1422-6405    

DOI:10.1159/000145417

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

Flexion creases on the toes of birds show remarkable similarities to human digital flexion creases, concerning both morphology and development. Muscle-free avian limbs were raised in the coelomic cavity or on the chorioallantoic membrane of chick embryos. Flexion creases were found to be formed after both procedures. From these experiments it may be concluded that regional differences, rather than mechanical factors, concerning the involved tissues are responsible for the formation of digital flexion creases. This may hold true also for human digital flexion creases.

ISSN:1422-6405    

DOI:10.1159/000145418

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

The omentum has raised a great deal of interest in recent years as it is a unique structure being highly vascular and accepting split skin graft readily. It is being used for various purposes not only within the abdomen but also outside it. However, so far, no work has been done regarding its size, although it is important to know before laparotomy whether there is ample omentum to serve the purpose. This study, in a series of 300 cases, not only determines the range of length and width of the omentum, but also correlates them with the height and wight of the patient so that one is able to predict the size, within limits, before laparotomy.

ISSN:1422-6405    

DOI:10.1159/000145419

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

Intrasellar and transplanted pituitaries removed from the same rats were studied using light microscopy, immunocytology, electron microscopy and ultrastructural morphometry following treatment with bromocryptine and/or estrone acetate. Ectopic lactotrophs of rats treated with bromocryptine showed an increase in storage granule size and number, which was not observed in the lactotrophs of corresponding intrasellar pituitaries. In lactotrophs of intrasellar and ectopic pituitaries, treatment with estrone acetate caused a decrease of storage granule size, while rough endoplasmic reticulum (RER) and Golgi region volume density increased. When rats were treated with a combination of bromocryptine and estrone acetate, intrasellar lactotrophs exhibited increased volume density and diameter size in forming granules as well as increased RER volume density. In ectopic lactotrophs, combined treatment led to a decrease in RER, volume densities of Golgi region and forming granules, as well as increased storage granule size. It can be concluded that ectopic lactotrophs were more sensitive to the inhibiting effects of bromocryptine treatment than intrasellar lactotrophs. Intrasellar lactotrophs were more susceptible to estrone acetate than bromocryptine treatment. As a result, the increased responsiveness of ectopic lactotrophs to estrone acetate was less conspicuous.

ISSN:1422-6405    

DOI:10.1159/000145420

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

In different growth regions of the long bones of normal rabbits the cell production in the growth plates were calculated from values of longitudinal bone growth determined with oxytetracycline and values of the degenerative cell size. The cell production was found to decrease similarly with increasing age for all growth regions. The rate of cell production for the various growth plates differed. There was little influence by age or localization on the size of the degenerative cells in the growth plate. Compared to other species such as rat and man the cell size in the rabbit is almost the same, whereas the difference in growth rate depends mainly on the cell production – mitotic activity – in the growth pl

ISSN:1422-6405    

DOI:10.1159/000145421

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

Central organization of the cardiac vagus has not been clarified. Retrograde changes produced in medulla oblongata neurons after section of vagal branches has favored the dorsal motor nucleus of the vagus (DMNX). Current information concerning the origin, course, and termination of vagal preganglionic fibers within cardiac ganglia is conflicting. The explicit purpose of this study was to determine if vagal fibers originated specifically within the DMNX proper. Fibers within the cardiac ganglia were labelled with 3 H-leucine following injection into the DMNX. 12 adult albino rats were studied. DMNX were injected with 25 µCi 3H-leucine reconstituted to 5 µl. Animals were sacrificed by transcardial perfusion following a 4-day survival period. Serial cross-sections of the caudal pons, medulla oblongata, and thoracic viscera were processed for autoradiography. DMNX possessed a heavy incorporation of the radiochemical. Label was observed within the axons of the vagi. Cardiac ganglia contained labelled vagal fibers in close proximity to the postganglionic somata. Cardiac ganglia containing labelled preganglionic vagal axons were located in the cardiac plexuses and in the epicardium. Results show a labelled vagal preganglionic input to cardiac ganglia from the DMN

ISSN:1422-6405    

DOI:10.1159/000145422

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

Granulosa cells from porcine ovarian follicles were cultured in vitro in standard medium and in medium supplemented with HCG. After culture the cellular 3β HSD enzymatic activity was evaluated and the cells were studied by TEM and SEM. A stereological evaluation of the smooth and rough endoplasmic reticulum was carried out. The results indicate that the cultured cells undergo a luteinization process which is more evident in the presence of HCG. In fact, in comparison with the controls, in these cells the enzymatic activity is higher, the rough endoplasmic reticulum decreases and the smooth endoplasmic reticulum increases, the cytoplasm shows lipid droplets and vesicular mitochondria. The cell surface develops a number of microvillus-like evaginations

ISSN:1422-6405    

DOI:10.1159/000145423

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

The effect of aging upon ability of the uterus to respond to a deciduagenic stimulus was studied by transmission electron microscopy. Particularly, subtle structural characteristics of decidualization were sought in stromal cells of uteri of aged rats. To negate effects of ovarian aging, rats 4, 10 and 20–24 months of age were subjected to bilateral ovariectomy and subsequent ovarian hormone injections. As deciduagenic stimulus, sesame oil was injected into the right uterus. The left served as the hormone primed control; and only antimesometrial endometrium was examined. Oil-injected uteri of 4- and 10-month-old rats developed deciduomata which histologically were similar to published descriptions. No decidual changes were observed in the aged oil-injected uterus. Therefore, the experimental and control uteri appeared similar. Luminal epithelial cells of aged rats differed from those of younger animals primarily in possessing more lysosomes and fewer surface microvilli. Stromal cells of aged rats differed more in shape and in quantity of cytoplasm, and in these cells lipofuscin deposits were identified more frequently. Moreover, leukocytes, plasma cells and macrophages were more numerous in the aged uteri. Failure of the aged uterus to decidualize could not be correlated with any morphologic changes. Results are correlated with previously proposed explanations for failure of aged uteri to decidualize and, accordingly, to maintain implanting embryo

ISSN:1422-6405    

DOI:10.1159/000145424

出版商:S. Karger AG    

年代:1981

数据来源: Karger

摘要:

The effect of biological (age and sex) and environmental factors (proteincalorie malnutrition and protein deficit) on 24 discontinuous cranial traits was investigated in Holtzman rats. The traits affected were (a) the interfrontal fusion, by age and nutrition; (b) the double posterior palatine foramen, by sex and nutrition, and (c) the double maxillary foramen, by nutrition. It is concluded that most of the traits studied were fairly stable. Nevertheless, it must be pointed out that taxonomic studies based on discontinuous cranial traits should be interpreted with care due to the influence of environmental and biological factors on the phenotypic expression of some of them.

ISSN:1422-6405    

DOI:10.1159/000145425

出版商:S. Karger AG    

年代:1981

数据来源: Karger