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H P Rohr

Publications and source records attributed to H P Rohr.

At least 19 recordsLinked to original sources
PubMed1989

[Benign prostatic hyperplasia: a stromal disease].

Morphometric studies show that benign human prostatic hyperplasia is a stromal disease caused by the activation of smooth muscle cells. This activation manifests itself in increased amounts of cytoplasmic organelles, which are preferably localized in the perinuclear region. Moreover, marked vesicular activity is present. Besides considerable overproduction of type I and III collagens, the architecture of the extracellular matrix is altered distinctly. In spite of strong evidence that androgens and estrogens regulate the growth of epithelial and stromal cells in the prostate and the induction of fibromuscular overgrowth in various animal models, the exact role of steroids in the pathogenesis of benign prostatic hyperplasia still remains to be elucidated.

Androgens↗
PubMed1987

Unilateral testicular disease: effect on the contralateral testis (morphometric study).

Unilateral testicular disease has been reported to damage the contralateral testis. In order to find out whether this detrimental influence is permanent in nature or can be avoided by therapeutic measures, and furthermore to quantify the damage, the following experiments were performed. Seventy-five rats were classified into the following five groups: I) testicular torsion persisting for eight hours; II) ipsilateral semicastration after torsion persisting for eight hours; III) semicastration; IV) sham operation as control; V) immunosuppression with azathioprine after torsion persisting for eight hours. The contralateral testes were removed two months later and perfused with fixative via the testicular artery. Stereologic techniques were employed to obtain quantitative morphologic data. Serum hormone levels were determined. The volume density of the contralateral germinal epithelium was not decreased two months after torsion for eight hours, torsion following by semicastration or torsion followed by immunosuppression. The same was true of the total volume of germinal epithelium per rat testis. The hormone levels remained essentially unchanged.

Animals↗
PubMed1987

Light-microscopic stereologic analysis of spontaneous and steroid-induced canine prostatic hyperplasia.

A combined light-microscopic and stereologic analysis of the canine prostate was performed under the following experimental conditions: intact and castrated dogs, spontaneous benign prostatic hyperplasia, intact and castrated dogs after treatment with testosterone, 5 alpha-dihydrotestosterone or 3 alpha-androstanediol in combination with estradiol. Regarding the absolute amounts of the glandular and stromal parts of the prostate as well as the glandular cells, no difference was found among the testosterone, 3 alpha-androstanediol and 5 alpha-dihydrotestosterone treated castrated dogs. Treatment with 5 alpha-dihydrotestosterone or 3 alpha-androstanediol in combination with 17 beta-estradiol induced a four-fold increase in glandular and a two-fold increase in stromal tissue. The glandular to stromal tissue ratio equals that found in spontaneous canine hyperplasia, which is indicative of the glandular type of spontaneous canine hyperplasia. Therefore, it can be stated that treatment with 5 alpha-dihydrotestosterone or 3 alpha-androstanediol combined with 17 beta-estradiol not only induces prostatic overgrowth but also leads to prostatic hyperplasia of the glandular type. However, the stereologic analysis of canine prostates following steroid administration shows that canine hyperplasia is primarily a glandular disease, while human benign prostatic hyperplasia shows more stromal activation.

Androstane-3,17-diol↗
PubMed1987

Correlation of biochemical (receptors, endogenous tissue hormones) and quantitative morphologic (stereologic) findings in normal and hyperplastic human prostates.

In previous light and electron-microscopic analyses human benign prostatic hyperplasia was shown to be predominantly a stromal disease; the aim of the present study was to correlate the stereological data with the levels of the endogenous tissue hormones (androgens, estrogens, progesterone) in normal (N) and hyperplastic human prostatic tissues (BPH). BPH tissue specimens were obtained by open prostatectomy (n = 25); normal prostatic tissue was obtained from kidney donors (n = 5). No statistically significant difference was found between normal and hyperplastic tissue. Testosterone BPH 0.69 +/- 0.44, N 0.25 +/- 0.12; 5 alpha-dihydrotestosterone BPH 7.0 +/- 2.9, N 4.2 +/- 0.7; progesterone BPH 0.059 +/- 0.022, N 0.058 +/- 0.005; estrone BPH 0.10 +/- 0.03, N 0.14 +/- 0.03; estradiol BPH 0.07 +/- 0.02, N 0.05 +/- 0.02; estriol BPH 0.02 +/- 0.01, N 0.04 +/- 0.02. Using a Spearman rank correlation coefficient a statistical analysis was performed for age, weight of the prostate, absolute stereological data and the endogenous prostatic hormones. As can be seen from the statistical analysis there is a poor correlation for 5 alpha-dihydrotestosterone and the amount of the glandular epithelium; otherwise no correlation of the endogenous tissue hormones with the stereological data investigated was found. These data show that the stromal overgrowth of benign hyperplasia is not reflected in the tissue hormone levels.

Gonadal Steroid Hormones↗
PubMed1987

[Salmonella daarle (6,8:y:e,n,x)--report on the isolation of a new serovar].

The serological and biochemical characteristics of a so far unknown serovar of Salmonella subspecies I with the serological formula 6,8:y:e,n,x (detailed antigenic formula = 6(1),8:y:e,n,x,z16, No. IP 5526/86 = H 428-36/86) is described. It has been named after a borough of Saarbrücken: Salmonella daarle.

Adult↗
PubMed1987

Endometrial morphology and peripheral hormone levels in women with regular menstrual cycles.

Endometrial biopsies from 90 women with regular menstrual cycles and a hormonal profile compatible with normal luteal function were morphometrically assessed using 11 different indices and the results were plotted in 48-hour periods around the day of the luteinizing hormone (LH) surge (LH +/- 0). The endometrial dating reached its highest significance from days LH -3/-2 to days LH +7/+8, when the changes occurred with a high degree of regularity regardless of the length of the preovulatory and postovulatory phases. It is proposed therefore that the dating of the endometrium should be related to the LH surge rather than to the "ideal" 28-day cycle. The results also seem to suggest the existence of a regulatory mechanism for the synchronization of follicular maturation and midcycle endometrial development. Further study of the factors involved in this mechanism may result in a better understanding of certain forms of unexplained infertility.

Adult↗
PubMed1986

Androgen and estrogen effect on guinea pig seminal vesicle muscle: a combined stereological and biochemical study.

A combined electron microscopic stereological and biochemical study of the smooth muscle cells of guinea pig seminal vesicles was performed in intact, castrated, castrated and dihydrotestosterone- or estradiol-treated adult animals. Castration led to cell atrophy as determined stereologically by a decreased single cell volume and biochemically by no change in DNA content coupled with an increase in the DNA concentration. Treatment of castrates with dihydrotestosterone restored both the stereological and biochemical parameters of the cell size to slightly supranormal levels. The estrogen-induced increase in muscle weight and DNA content appeared to be due only to hyperplasia of muscle cells and not to a proliferation of fibroblasts or to infiltration by inflammatory cells. In all treatment groups, including the estrogen-treated castrates, more than 95% of the cells in the tissue were smooth muscle cells, and there was no evidence that polyploidy contributed to changes in DNA levels. In addition, in the estrogen-treated muscles, DNA concentration remained high, and the stereologically determined cell size remained low. Therefore, both morphological and biochemical evidence indicate that androgen induces hypertrophy, whereas estrogen induces hyperplasia of muscle cells. The correction of stereological and biochemical data validates the application of stereological cell size determination for smooth muscle cells in organs that hardly can be separated into stromal and epithelial components; eg, the prostate.

Animals↗
PubMed1985

Correlated biochemical and stereological studies on testosterone metabolism in the stromal and epithelial compartment of human benign prostatic hyperplasia.

The growth and function of the human prostate is dependent upon a continuous supply of androgens, mainly 5 alpha-dihydrotestosterone, the 5 alpha-reduced metabolite of testosterone. Within the human prostate dihydrotestosterone is thought to be the intracellular mediator of androgen action. Although it is well documented that dihydrotestosterone is evenly distributed between the stromal and epithelial compartment of the prostate, the anatomical localization of dihydrotestosterone formation within the normal and hyperplastic prostate is still not established. To provide further insight into this problem we have measured, under conditions approximating the in vivo state, dihydrotestosterone formation in prostates obtained from 4 men with normal prostates and 36 men with benign prostatic hyperplasia. In addition to this we have performed histometric analysis of the cellular composition of the samples incubated, in order to correlate the morphological and the histochemical findings. Dihydrotestosterone is the major metabolite, and androstanediol and androstenedione were formed in smaller quantities. Under the given conditions metabolite formation from testosterone increased linearly for 60 minutes and the half maximum rate of dihydrotestosterone formation (Km) was observed at about 1.25 X 10(-6) M testosterone, a value similar to that reported for rat prostatic nuclei and human prostatic tissue. Dihydrotestosterone formation was higher in hyperplastic prostates than in the normal prostate. (Student's t test: p less than 0.05). The stroma in both the normal and hyperplastic tissue converts testosterone to dihydrotestosterone very actively. No significant relation was found between dihydrotestosterone formation and the per cent distribution of the stromal and epithelial compartment in any sample studied. In conclusion, our results are compatible first with the thesis that the rate of dihydrotestosterone formation is increased in the hyperplastic prostate and secondly with the concept that the rate of dihydrotestosterone formation is approximately the same in the epithelial and stromal compartments of the prostate.

Androstane-3,17-diol↗
PubMed1984

Human skin grafts on nude athymic mice: a light microscopic stereological study.

A morphometric procedure is presented, which allows quantitative information to be obtained from the epidermis at the light microscope level. The application of this procedure to human skin grafted to the nude mouse revealed acanthosis of the grafted epidermis compared to the original donor skin. All epidermal layers were thicker, but the increase in the granular layer was especially marked. The ratio of the basement membrane surface to the epithelial surface showed no significant change. A possible explanation for the acanthosis of the graft might be the higher mechanical stress on the nude mouse compared to the original site on the abdomen. This adaptation of the grafted epidermis does not limit the usefulness of this animal model for dermatological research, when it is assessed by objective methods, allowing statistical comparison as described here.

Animals↗
PubMed1984

Do's and don'ts in stereological pathology or possibilities of stereological-biochemical correlation in uropathology.

The problems and the interpretation of combined stereological-biochemical investigations in benign prostatic hyperplasia (BPH) research are discussed. As BPH is characterized by a primary stromal enlargement the role of the smooth muscle cell (SMC) is focussed. For determination of the single cell volume of the SMC several methods are applicable leading to different results. Thus interpretation of these results has to be done with caution. Finally as an example there is a discussion of a correlation of stereological-biochemical dates of human prostatic tissue samples.

Adult↗
PubMed1983

[Vascular replacement of small caliber arteries--a new bovine collagen prosthesis].

A new bovine collagenic prosthesis (Solcograft P) was tested in animal experiments. In 45 dogs the infrarenal abdominal aorta was substituted. During a follow-up period of up to 18 months the functional rate amounted to 88%. Joint-crossing iliaco-femoral bypasses were implanted in 31 dogs, 5 times in both sides. For the new bovine collagenic graft the functional rate ran up to 83%, during a follow-up period of 9 months. A wound infection was observed twice in the inguinal region thus exacting the removal of the prosthesis. An aneurysm was not observed. In our opinion the satisfying results are due to the compliance of the new prosthesis which is similar to natural artery.

Animals↗
PubMed1983

Smooth muscle cell of the canine prostate in spontaneous benign hyperplasia, steroid induced hyperplasia and estrogen or tamoxifen treated dogs.

Human benign prostatic hyperplasia is a predominantly stromal hyperplasia with accumulation of connective tissue. The main ultrastructural finding, which may be causal, is an activation of the smooth muscle cells, as seen by an increase of the volume density of the organelles within these cells. The dog is widely used as an animal model for human prostatic hyperplasia in spite of several differences. In this work the smooth muscle cells of the spontaneous and steroid-induced (by treating castrates with dihydrotestosterone and estradiol) prostatic hyperplasia of dogs were analysed by electron microscopical morphometry, and compared to estrogen or tamoxifen (antiestrogen) treated dogs as well as to untreated or castrated control dogs. The results clearly show that the prostatic smooth muscle cells of the dog can be activated by estrogen as well as tamoxifen, which proves the estrogenic side activity of the latter. In marked contrast to that, neither in the spontaneous nor in the steroid-induced prostatic hyperplasia could an activation of the smooth muscle cells be found. This is a most important difference from human benign prostatic hyperplasia, which limits the use of this animal model, and it might even be the explanation of the different reaction of human and canine prostatic hyperplasia to therapeutic hormonal manipulations.

Animals↗