摘要:

In order to study the effects of unilateral short length immobilization on the contralateral gastrocnemius muscle (GM), length measurements were conducted on photographs taken in the active condition (tetanic plateau). Comparison of geometry of experimental and control muscles was made at optimum muscle length. The results show that a process occurred in the muscle which can be ascribed predominantly in terms of atrophy. This atrophy did not reach a maximum after 4 weeks but gradually increased in time. The altered conditions imposed on the muscle changed its architecture. It was shown that variables of the contralateral GM muscle are not representative of those of normally used muscles and should therefore not be used as control muscles for the determination of immobilization effects.

ISSN:1422-6405    

DOI:10.1159/000147253

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The present work is to study neural differentiation in melanocytes in relation to the cell cycle and UV exposure. Whole skin organ cultures of vitiliginous skin were exposed to a pulse of UV with and without prior Adriamycin treatment. It was observed that the highly dendritic marginal melanocytes are destroyed on UV exposure during the depigmentation phase but not during repigmentation. The melanocytes are resistant to UV destruction during the G2 phase as seen on Adriamycin treatment. They show a prominent increase in dendricity as well as biphasic activity to produce increased melanin and noradrenaline. Thus, the melanocytes form a UV-sensitive neural network in the skin. These responses are reminiscent of the repigmentation and depigmentation of coat color in animals exposed to extreme variations in the day/night cycles as seen at the poles.

ISSN:1422-6405    

DOI:10.1159/000147254

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The X-linked testicular feminization mutation (Tfm/Y) in the mouse is characterized by androgen insensitivity of the target cells. The aim of this study was to examine sexually dimorphic development of the submandibular gland of Tfm/Y mutant mice in comparison with those of wild-type male, wild-type female and heterozygous Tfm female mice. In either 30- or 90-day-old wild-type male mice, the granular convoluted tubules (GCT) of the glands were more developed, and the relative occupied areas (ROA) of GCT were superior to those of the age-matched wild-type and heterozygous Tfm females. In androgen-insensitive Tfm/Y mice, the glandular structures rather resembled the female glands, showing lower values of the ROA of the GCT. Sex differences in the mitotic rate were observed at 30 days of age, being significantly higher in the wild-type male GCT than in the female GCT. Thereafter, the mitotic rate of the wild-type male GCT declined to the female levels by 90 days of age. The mitotic rate of GCT in Tfm/Y mutants was as low as those of the females during observation periods. An other three regions, the acini, the intercalated ducts and the excretory striated ducts, were not significantly different in either the ROA or the mitotic rate among wild-type males and females, and Tfm/Y. On the other hand, either the ROA or the mitotic activity of GCT of the glands in Tfm/Y mutants was completely unaffected by 5α-dihydrotestosterone (DHT). The glands of heterozygous Tfm females were responded to DHT, but the ROA of their GCT was inferior to those in wild-type females, showing the mosaic expression of the X-chromosome in activation in heterozygous Tfm females. The present study suggests that in androgen-insensitive Tfm/Y mice, both the glandular structures and the mitotic activities were rather similar to those of the females

ISSN:1422-6405    

DOI:10.1159/000147255

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The histochemical distribution of the enzyme cytochrome oxidase (CO) was explored in the globus pallidus (GP) of the rat, and it was compared with the distribution of acetylcholinesterase (AChE), another well-known enzyme of the basal ganglia in mammals. This neurochemical research illustrates two prominent findings. In the first place, a regional compartmentalization was detected in the pallidal distribution of CO, in which dorsal territories of the GP exhibited a more abundant presence of this enzyme. In addition, the distribution of this mitochondrial enzyme was not uniform all over those dorsal pallidal territories. Thus, the pallidal concentration of CO was gradually decreasing dorsoventrally and lateromedially, and, sometimes, areas highly stained for CO were intermingled with zones in which this enzyme was less conspicuous. In the second place, the pallidal distribution of AChE was the opposite of that found for CO (i.e. more abundant in ventral and medial territories of the GP). The functional significance of these findings is discussed in the light of the heterogeneous hodological neuroanatomy of the GP of rodents.

ISSN:1422-6405    

DOI:10.1159/000147256

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The dorsal lingual surface of the common tree shrew was examined by SEM after treating it with HC1 to remove the mucous substance. Filiform (FI), fungi-form (FU) and circumvallate papillae (CI) were observed. The FI exhibited a small circular bulge surrounded by anterior and posterior filamentous processes. FU were scattered among the FI. There were 3 CI separating the anterior 4/5 from the posterior 1/5 of the tongue. In addition, a group of conical projections with caudal orientation was found anterior to the palatoglossal fold on each side of the tongue. Microridges were widely observed on the entire dorsal lingual surface, except on the free surface of FI processes.

ISSN:1422-6405    

DOI:10.1159/000147257

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The distribution of carbonic anhydrase (CA) was studied in the testis and epididymis of mature, male rabbits using a cobalt precipitation method. CA was found only in the endothelium of the capillaries in the testis. The epididymal duct was divided into initial, middle and terminal segments. Strong cytoplasmic CA was present in the apical cells in the initial and middle segments. Vacuoles with CA staining in the membranes were found in the principal cells in the middle segment. Intensely stained basal cells were present in the terminal segment. In the last part of the terminal segment and the first of the ductus deferens the basolateral cell membranes were also stained. The function of the enzyme is discussed especially in relation to acidification of the epididymal fluid and facilitation of CO2 diffusion.

ISSN:1422-6405    

DOI:10.1159/000147258

出版商:S. Karger AG    

年代:1992

数据来源: Karger