摘要:

Synapses between neurons with corticotropin-releasing-factor-(CRF)-like immunoreactivities and other immunonegative neurons in the hypothalamus of colchicine-treated rats, especially in the paraventricular nucleus (PVN) and the supraoptic nucleus (SON) were observed by immunocytochemistry using CRF antiserum. The immunoreactive nerve cell bodies and fibers were numerous in both the PVN and the SON. The CRF-containing neurons had synaptic contacts with immunonegative axon terminals containing a large number of clear synaptic vesicles alone or combined with a few dense-cored vesicles. We also found CRF-like immunoreactive axon terminals making synaptic contacts with other immunonegative neuronal cell bodies and fibers. And since some postsynaptic immunonegative neurons contained many large neurosecretory granules, they are considered to be magnocellular neurosecretory cells. These findings suggest that CRF functions as a neurotransmitter and/or modulator in addition to its function as a hormone.

ISSN:1422-6405    

DOI:10.1159/000146097

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

It has been established that a low level of secretory activity persisted in seminal vesicles of guinea pigs long after castration and that this may be due to a higher extratesticular androgen level in this animal. A RIA study revealed that the normal serum testosterone concentration of the guinea pigs was comparable to that of the rats, but the basal serum testosterone level after castration was ten times higher than rats under a similar condition. It was also shown that cyproterone acetate did not significantly lower the basal serum testosterone concentration in the castrated guinea pigs. The higher basal serum testosterone level is believed to be responsible for the slow and incomplete regression of this gland in the guinea pigs. There was a significant reduction in wet weight of the seminal vesicles after the treatment of castrated guinea pigs with cyproterone acetate. Ultrastructural study showed that there were both qualitative and quantitative changes in the cytoplasmic organelles. The Golgi apparatus further reduced in size and in the number of associated vesicles and vacuoles. There was a marked decrease in the number and size of secretory granules and lysosomes and an increase in the degree of undulation of the basement membrane. Accumulation of lipid droplets and glycogen was commonly observed. All these morphological evidences showed that further regression of the castrated guinea pig seminal vesicles can be achieved by cyproterone acetate treatment.

ISSN:1422-6405    

DOI:10.1159/000146098

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Sutural morphogenesis was studied in calvariae of fetal and newborn 16- to 26-day postconception C57B1/6J mice. The squamoid pattern charactefistic of most calvarial sutures appeared to be established during the phase of approach of the adjacent bone territories as they assumed different ecto/ifendocranial planes within the desmocranium. When this stratification failed, apoptosis, a form of cell death, was seen to occur upon physical contact of the leading osteogenic cells of each heterotopic bone territory. Apoptosis appeared as part of a secondary morphogenetic mechanism preventing physical contact and resultant fusion of adjacent mineralized zones, as well as enhancing appearance of the usual pattern of overlap of calvarial sutures.

ISSN:1422-6405    

DOI:10.1159/000146099

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The effect of hypothyroidism upon the morphology and the function of several endocrine glands was studied in radiothyroidectomized male rats. It was found that T3, T4, insulin, prolactin and corticosterone levels were significantly lower in hypothyroid rats. TSH levels were significantly higher in these animals while no changes were depicted in testosterone levels. The administration of T4 drew back to normal range the above-mentioned altered serum hormone levels. The studies performed with light microscopy revealed alterations only in the TSH secretory cells of the adenohypophysis. Conversely, when using the electron microscope to study the different endocrine glands, clear alterations were depicted in the TSH and prolactin secretory cells of the adenohypophysis, as well as in the pancreatic B cells and the cells of the zona fasciculata of the adrenal cortex. No abnormal changes were demonstrable at the level of the seminiferous tubules of the testis. All the above morphological changes were corrected by the administration of T4 to hypothyroid rats. These results suggest that the hypothyroid state is a complex hormonal dysfunction rather than a single hormonal defect. The secretory alterations are accompanied by fine cellular alterations in the corresponding glands.

ISSN:1422-6405    

DOI:10.1159/000146100

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Degeneration of the knee joint and increase of anterior-posterior tibial displacement are resulting from total meniscectomy, especially in knees with anterior cruciate deficiency. Vascularisation of the meniscus was studied in 12 cadaver knees after latex injection of vessels. Vascularisation of the anterior and posterior horns was found to be much better than that of the body of meniscus. All vessels originated from the politeal artery, but variably in importance, and formed the perimeniscal and subsynovial network. 11 peripheral meniscus tears (8 freshly injured, 3 ruptures older than 2 months) were repaired by refixation, followed by immobilisation for 6 weeks. Arthroscopy 3 months postoperatively showed complete healing of all tears. Clinical examinations – follow-up for 14 months – showed no signs of rerupture in any of the patie

ISSN:1422-6405    

DOI:10.1159/000146101

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The in vivo effects of 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] on cellular structure and response, matrix metachromasia and mineralization have been studied in the epiphysis and growth plate of humeri in normal neonatal mice. A relatively low dose of the metabolite, 50 ng/kg body weight, significantly increased the overall size of humeral growth plate, the zone of proliferating cells and that of hypertrophic chondrocytes. The response of the tissue to the metabolite changed with the increase in dose administered so that it was only the zone of proliferation that still showed increases in size in comparison to untreated controls. 1,25(OH)2D3 led to an increase in the metachromatic reaction of the cartilage matrix in the chondroblastic zone, and to marked increase in matrix mineralization in the hypertrophic zone. Qualitative changes were also noted in the structure of chondrobalsts and hypertrophic chondrocytes. 1,25(OH)2D3 affected the osteoblastic and osteocytic populations of cells along the metaphysis and diaphysis of the humerus. High doses of 1,25(OH)2D3 brought about distinct atrophic changes in the above cells. Chondrocytes in the epiphysis were found to synthesize type I collagen and fibronectin. These findings indicate that excessive doses of 1,25(OH)2D3 in an intact growing animal affect the normal differentiative pathway of prechondroblasts and thereby affect long bone development

ISSN:1422-6405    

DOI:10.1159/000146102

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Morphological and functional changes of pituitary LH/FSH cells in the female rat were investigated using the parameters on the radioimmunoassay, immunohistochemistry and ultrastructure. Changes in immuno-stainability, populations of intensely immunostained LH and FSH cells and total volume of secretory granules were correlated with the changes in pituitary LH and FSH contents during the estrous cycle. The immunohistochemical feature of gonadotropin release is the transformation of intensely immunostained gonadotrophs into the weakly stained ones. Secretory granules of small diameter (less than 150 nm) were numerous just before LH and FSH surges then sharply declined along with LH and FSH surges. The number of secretory granules of large diameter (larger than 150 nm) also decreased when LH and FSH surges took place. Then the number increased progressively until 17.00 h on the day of diestrus, corresponding to the increase in pituitary LH and FSH contents. It is suggested that small secretory granules are a release pool while large ones are a reserve pool.

ISSN:1422-6405    

DOI:10.1159/000146103

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

It was recently demonstrated that C cells, mucosubstances, and the intermediate filament epidermal keratin are present in solid cell nests (SCN) of the thyroid. The reliability and usefulness of these markers in detecting these ultimobranchial nests have, so far, not been comparatively investigated. In the light of this, a study for the presence of these tracers in SCN at different stages of postnatal life was undertaken. The existence of carcinoembryonic antigen (CEA) in this gut-derived tissue was also searched for. Epidermal keratin was present in the epidermoid-like cells from all SCN studied; calcitonin-immunoreactive C cells and mucosubstances did not always occur. These findings reveal that this cytokeratin would remain as a potential marker to detect and trace back the ultimobranchial tissue component of the thyroid in earlier stages of development. The presence of CEA in practically all SCN surveyed would further support the view that they originate in the gut. This antigen would also be of great value for histological identification of these nests. The usefulness of these markers for the interpretation of the histogenesis of some ultimobranchial-related thyroid neoplastic growths, specifically the medullary and mucoepidermoid carcinomas, is briefly discussed.

ISSN:1422-6405    

DOI:10.1159/000146104

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

In a previous study we reported that castration of adult male rats resulted in femoral osteoporosis 4 months later. The present study tested the effects of dichloromethylene biphosphonate (Cl2MBP, formerly Cl2MDP), a bone resorption inhibitor, on the development of osteoporosis in femora of adult castrated male rats. One-year-old male Holtzman rats were assigned to three groups: sham-operated controls; castrated-no treatment; castrated+ Cl2MBP injections 3 times/week. The animals were sacrificed 4 months later. Femora from untreated castrated rats were osteoporotic, confirming our earlier study. Femora from Cl2MBP-treated castrates did not differ from those of controls and were significantly denser and more robust than those of untreated castrated rats. The results indicated that Cl2MBP treatment started immediately after castration prevented the development of femoral osteoporosis in adult castrated male rats.

ISSN:1422-6405    

DOI:10.1159/000146105

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Bovine parotid gland intralobular ducts were frequently found to contain an intraepithelial granular cell type, adjacent to the basement membrane. Granular cells were non-migratory and polymorphic in appearance, with strong cytoplasmic basophilia and acidophil metachromatic granules. Such cells were not found in the bovine mandibular and sublingual glands. It is proposed that the granular cell may be similar or identical to the globule leucocyte cell type and functionally associated with the parotid gland. A possible role for parotid gland granular cells in ruminant mucosal immunity is also discussed.

ISSN:1422-6405    

DOI:10.1159/000146106

出版商:S. Karger AG    

年代:1985

数据来源: Karger