Chung I

The rat prostate is a complex ductal system with branches and subbranches extending from one end to another. Owing to the relative distance of various regions of the duct from the urethra, the entire length of the ductal system can be arbitrarily divided into three segments, i.e., the proximal, intermediate, and distal segments. The present study was carried out to assess the regional variation in cellular activities in this ductal system. Ventral prostates from adult Sprague-Dawley rats were di

Our future research should take advantage of this knowledge to devise therapeutic strategies aimed at eradicating prostate cancer.

The rat prostate is innervated by pelvic and hypogastric nerves through a single pelvic ganglion, removal of which would result in complete denervation of the prostatic complex. The present study was conducted to investigate the effect of denervation on the rat prostate. Adult Sprague-Dawley rats of 300 g in body weight were divided into two groups. Bilateral pelvic ganglion denervation was performed in one group of animals; the other group received a sham operation. Three weeks later, animals w

The present study was conducted to isolate and to characterize stromal cells from the human prostate and to study the effects of androgen and different growth factors in this model system. Benign prostatic hyperplasia (BPH) tissue samples were obtained from transurethral resection of the prostate (TURP). Tissue specimens were mechanically and enzymatically dissociated by treatment with DNAse and collagenase. Epithelial cells were separated from stromal cells by discontinuous Percoll gradient cen

The growth of the prostate gland has been considered to be controlled exclusively by endocrine means. The abundance of alpha adrenergic and muscarinic receptors and nerve fibers suggests that the autonomic nervous system may in fact play a role in the growth maturation and secretory functions of the prostate. The predominant adrenergic input to the prostate is from short adrenergic neurons, while cholinergic nerves are closely related to the glandular epithelium, presumably affecting a secretory

The present study was conducted to study the interaction between epidermal growth factor (EGF) and transforming growth factor-beta (TGF-beta) in benign human prostatic epithelial cells in culture. Primary cultures of human prostatic epithelial cells were grown in complete WAJC, which consisted of WAJC-404 medium and, in addition to other defined additives, EGF and bovine pituitary extract (BPE). Incomplete WAJC contained the same composition except EGF and BPE were deleted. TGF-beta was added in

Two-dimensional protein profiles of human semen, prostatic fluid, and seminal vesicle fluid were compared to demonstrate changes in the protein composition of human semen before and after liquefaction. Semen specimens were obtained from a volunteer. Prostatic fluid specimens were collected by rectal massage from patients visiting a urology clinic. Samples of seminal vesicle fluid were collected by needle aspiration from isolated seminal vesicles, which were removed at surgery. All specimens were

To study the neuronal and hormonal control of prostatic secretion, the prostatic urethra was cannulated in urethane anesthetized rats. The volume of prostatic secretion was measured following infusion of cholinergic and adrenergic agonists intact animals. Prostatic secretion was elicited by norepinephrine, phenylephrine and carbachol; but not by clonidine, isoproterenol, pilocarpine, or acetylcholine. Phenylephrine and norepinephrine infusions caused a high initial rate of secretion, which then

Ventral prostates from adult Sprague-Dawley rats at different days postcastration were cut into one to two mm.3 pieces and incubated in medium containing S35-methionine (100 uCi/ml.) at 37C under 95% oxygen and 5% carbon dioxide for four hours. The incubated tissues were subjected to two-dimensional electrophoresis and radiofluorography. Over 100 spots were developed in the fluorograms. Three groups of spots, representing cytoskeletal proteins, androgen-dependent proteins and castration-induced

TGF-β regulates a wide range of biological functions including embryonic development, wound healing, organogenesis, immune modulation, and cancer progression. Interestingly, TGF-β is known to inhibit cell growth in benign cells but promote progression in cancer cells; this phenomenon is known as TGF-β paradox. To date, the mechanism of this paradox still remains a scientific mystery. In this review, we present our experience, along with the literature, in an attempt to answer this mystery. First

TGF-beta regulation of immune homeostasis has been investigated in the context of cytokine knockout (TGF-beta null) mice, in which particular TGF-beta isoforms are disrupted throughout the entire organism, as well as in B and T cell-specific transgenic models, but to date the immunoregulatory effects of TGF-beta have not been addressed in the context of an in vivo mouse model in which multi-isoform TGF-beta signaling is abrogated in multiple leukocyte lineages while leaving nonhemopoietic tissue

These results demonstrated that a loss of sensitivity to TGF-beta results in the accumulation of multiple layers of epithelial cells in the proximal region of the ventral prostate. This abnormal growth illustrates that TGF-beta plays an important role in regulating prostate growth. The current transgenic system can be used as an experimental model to study the functional role of TGF-beta in prostatic growth and function.

In a preliminary study, we observed that TGF-beta1 induced both proliferation and growth arrest in prostatic stromal cells, depending on the concentration of TGF-beta1 used in the culture medium. In this study, we explored possible mechanisms of this dual effect of TGF-beta. Primary cultures of prostatic stromal cells, established from clinical surgical specimens and treated with low doses of TGF-beta1 (0.001-0.01 ng/ml), resulted in an increase in cell proliferation. The addition of neutralizin

The mechanism of the observed synergistic effect of prolactin and androgen on the lateral lobe of the rat prostate is not established. The observation that prolactin alone delayed the rate of loss of weight, protein, and DNA of the lateral lobe in castrated rats has led us to question the assumption that the effect of prolactin is produced by a modification of recognized androgen-induced intracellular changes. The present study was conducted to explore whether or not the sites of prolactin actio