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G Aumüller

Publications and source records attributed to G Aumüller.

At least 145 records · Page 8Linked to original sources
PubMed1980

Cytochemistry and biochemistry of acid phosphatases. I. Cytochemistry and isoelectric focussing of acid phosphatases of the rat ventral prostate.

Acid phosphatases of the rat ventral prostate were studied cytochemically using different substrates. The results were compared to findings on isoelectric focussing gels stained for acid phosphatase activity. This is a highly specific and reproducible method which allows the distinction between secretory androgen-dependent and lysosomal acid phosphatases. Activity of lysosomal acid phosphatase was increased after castration, while the activity of the secretory enzyme gradually decreased after androgen deprivation. None of the substrates tested was selectively hydrolyzed by either secretory or lysosomal acid phosphatase. Phenylphosphate, creatine phosphate and choline phosphate were found to be inappropriate substrates for histochemical purposes, however, reproducible results were obtained with alpha-naphthylphosphate, beta-glycerophosphate and p-nitrophenylphosphate. The method of isoelectric focussing (pH range 4.0--8.0) of enzymes with subsequent histochemical staining demonstrated lysosomal enzymes at pH 7.9 and 8.2 respectively. Small amounts of identical enzymes were found in liver, kidney, blood or epididymis. Secretory acid phosphatases were focussed at pH 5.5, 5.6, 5.65 and 7.15. Similar enzymes have been identified in epididymis, kidney, liver and pancreas. These results indicate that 1) at present no "specific" substrate for prostatic secretory or lysosomal acid phosphatases is available and 2) that no prostate-specific "prostatic acid phosphatase (PAP)" exists in the rat ventral prostate.

Acid Phosphatase↗
PubMed1980

Intracellular distribution of adenine and 5-hydroxytryptamine in megakaryocytes isolated by density gradient and velocity sedimentation from bone marrow.

Megakaryocytes were isolated from rat and guinea pig bone marrow by Percoll density and/or elutriator centrifugation. As compared with the suspension of bone marrow an enrichment of factor 530 with a recovery of 34% can be achieved if a combination of both methods is applied.--The pattern of DNA percentage distribution in isolated cells paralleled the polyploidy found in megakaryocytes of the bone marrow. As determined by scanning cytophotometry and impulse cytophotometry the percentage distribution was maximal for the 16 C cells.--Exogenous [3H]adenine was incorporated by isolated megakaryocytes via a time and concentration dependent process showing two different affinities, Kt1 = 11 nM, V1 = 0.07 pmol/min per 10(5) cells; Kt2 = nM, V2 = 0.21 pmol/min per 10(5) cells.--Autoradiographic studies quantificated by means of the "probability circle" and "percent density" analysis showed that [3H]5-hydroxytryptamine (5-HT) accumulated in the osmiophilic dense bodies in contrast to [3H]adenine (metabolite) which was found mainly in the cytoplasm.

Adenine↗
PubMed1979

Experimental studies of apocrine secretion in the dorsal prostate epithelium of the rat.

Rat dorsal prostate epithelium was studied in intact adult animals, in animals castrated for three days and in rats after inhibition of prolactin secretion. Thin sections, electron-microscopic autoradiographs and freeze-fracture replicas were used to analyze the process of apocrine secretion in this gland. The rough endoplasmic reticulum and the Golgi apparatus of the secretory cells are well developed, but secretory granules are absent. The only sign indicating release of secretory material is the appearance of blebs originating from the apical plasma membrane. Freeze-fracture replicas of the apical plasma membrane reveal that the blebs develop randomly from the bases of microvilli-like protrusions. In vitro pulse labeling of the proteins using 3H-leucine resulted in a labeling of the apical blebs. A post-castration period of three days was sufficient to reduce drastically the number and size of the apical blebs conhree weeks by application of lisuride, a synthetic ergot alkaloid, also induced regressive changes in the secretory cells. The apical blebs were still present, but they were shrunken and their content appeared condensed. These experimental conditions proved that the apical blebs are closely related to the functional activity of the cells and are interpreted as true apocrine secretion in the rat dorsal epithelium.

Animals↗
PubMed1978

Fine structure of rat prolactin cells after treatment with a long acting depot contraceptive.

Adult intact female rats were injected with norethisterone oenanthate (NOe), with or without simultaneous administration of CB-154, or with oestradiol benzoate (OeB). The ultrastructure of prolactin (PRL) cells due to the various treatment regimens was investigated and compared with the situation found in controls. Both after treatment with NOe or NOe plus CB-154, the number of PRL cells increased and displayed various ultrastructure signs of stimulation. The determination of serum PRL levels coincides with these morphological findings. In all treated animals mammary gland DNA content was significantly increased. The results presented indicate that proliferative changes in the rat mammary gland depend predominantly on the presence of progestogenic activities additionally to PRL, whereas the effect of oestrogens was regarded as an indirect effect via their PRL-stimulatory action.

Animals↗
PubMed1978

Fine structure of Sertoli cells in the rat testis after hypophysectomy, testosterone treatment and re-involution.

Using thin sections and freeze-etch replicas the fine structure of the Sertoli cells of the rat testis was investigated after hypophysectomy, testosterone treatment and re-involution. 41 days after hypophysectomy the Sertoli cells contain numerous dense bodies and remnants of degenerating spermatocytes and spermatids. The Sertoli cell junctions are most prominent. The membranes of neighbouring cells are folded into several layers. Freeze-fracture replicas reveal a normal arrangement of Sertoli cell tight junctions with linear array of membrane particles preferentially on the B-face and complementary grooves on the A-face. The geometric pattern of the ridges is varying with respect to the basal, intermediate and apical portions of the lateral Sertoli cell membranes. Since no major changes of the size, distribution and localization of the Sertoli cell junctions were observed in the different experimental groups these junctions, once formed, are inferred to be independent from hypophyseal hormones.

Androgens↗
PubMed1977

The collicular recess organ: evidence for structural and secretory specialization of the ventricular lining in the collicular recess.

The collicular recess organ and adjacent portions of the collicular recess were studied by light microscopy, scanning electron microscopy and transmission electron microscopy. In the collicular recess, the ventricular wall contains folds and is well vascularized. The adluminal ependymal cells generally bear kinocilia and microvilli on their ventricular surface. Among the cilia, many secretory droplets, some axons, and few supraependymal cells are seen. Various stages of apocrine ependymosecretion are observed. In addition to tanycytes, coelocytes are found scattered throughout the ependymal lining of the collicular recess. Coelocytes, characterized by lumina containing cilia and a few microvilli, are accumulated in ependymal and hypependymal positions of the collicular recess organ at the roof of the collicular recess.

Animals↗
PubMed1977

Lipopigment fine structure in human seminal vesicle and prostate gland epithelia.

The fine structure of lipopigments normally found in prostatic and seminal vescile epithelial cells of elderly men is described and compared to findings in human fetal and hypophysectomized rat accesory sexglands. In the prostate gland lipopigments are supposed to be a sign of reduced metabolic activity, whereas in the seminal vesicle lipopigment formation seems to indicate not only high functional activity but also regressive changes.

Age Factors↗
PubMed1977

The heart: a target organ for estradiol.

Autoradiographic studies of rat heart reveal that tritiated estradiol concentrates in cell nuclei of the myocardium of the atria and auricles, similar to the myometrium of the uterus. This suggests that estrogen has a direct effect on atrial myocytes through which its "protective" action may be mediated. Cardiac glycosides that are known to exert estrogen-like effects on classical estrogen target tissues, such as uterine muscle, endometrium, vagina, and mammary gland, probably act on atrial muscle through a genomic, steroid hormone-like mechanism of action.

Animals↗
PubMed1976

Seasonal changes in the fine structure of the accessory sex gland in the mole (Talpa europaea).

The mole has a single pair of accessory sex organs with features of both the prostate and the seminal vesicle, for which the term prostate gland is not appropriate. Seasonal changes occuring in this gland were related to four periods: a) the quiescence period, b) the maturation period, c) the active period and d) the involution period. During the quiescence period the cuboidal epithelial cells display a quasi-embryonic fine structure and are sparse in cytoplasmic organelles, but rich in glycogen and lipopigment. With the onset of sexual activity glycogen and lipopigment disappear and the rough endoplasmic reticulum as well as the Golgi apparatus begin to proliferate. The fully active gland is lined by a low epithelium with parallel stacks of rough endoplasmic reticulum, a large Golgi apparatus and several lysosomes and secretory granules. In the involution period the gland collapses and the epithelial cells are eliminated by hetero- and autophagic processes. During this period a great number of presumably endocrine cells were observed. The results were compared with findings in experimental studies and those on postnatal development of accessory sex glands in laboratory animals.

Animals↗
PubMed1976

[Neurological manifestations of Whipple's disease].

Three consecutive cases of Whipple's disease observed by us in recent years have involved neurologic symptoms, i.e. psychoorganic syndromes, gaze palsy, nystagmus, masseteric and pharyngeal myoclonus or papilledema. In one case mononuclear cells in the cerebrospinal fluid, most probably of ependymal origin, were loaded with periodic-acid-Schiff (PAS) positive granules. On treatment with antibiotics the neurologic signs cleared considerably or completely. The findings suggest (a) that neurologic involvement Whipple's disease may not be so uncommon as appears from the literature, (b) that examination of the spinal fluid with PAS staining may be helpful in the diagnosis of such cases, and (c) that neurologic involvement in Whipple's disease may also be amenable to treatment with antibiotics.

Adult↗
PubMed1976

Internal surface and fine structure of the rat seminal vesicle.

The seminal vesicle of the rat was studied with scanning and transmission electron microscopy. The internal surface of the organ is partitioned into small areas by a system of elevated ridges of connective tissue and covered by a columnar epithelium. This consists of small basal cells, presumably reserve elements, and larger ones containing the typical cell organelles involved in protein synthesis. The surface of the cell is covered with slender microvilli, varying in height and number from region to region. It is suggested that they are involved in the maintenance of hydration and/or regulation of low molecular weight substances in the secretion product. The latter develops from small granules which pass the apical cell border and then fuse together as larger drops.

Animals↗