Expression of glutathione peroxidases in the adult male rat reproductive tract

OBJECTIVE

To evaluate the messenger RNA (mRNA) expression of three glutathione peroxidase isoforms in the male reproductive tract and to further characterize testicular glutathione peroxidase expression.

DESIGN

Analysis of glutathione peroxidase levels in untreated animals.

INTERVENTION(S)

32P-labeled DNA probes were derived from known complementary DNA (cDNA) sequences for classic cellular glutathione peroxidase, phospholipid hydroperoxide glutathione peroxidase, and secretory epididymal glutathione peroxidase, and used to evaluate mRNA levels in each tissue by Northern blot hybridization.

MAIN OUTCOME MEASURE(S)

Glutathione peroxidase mRNA concentrations.

RESULT(S)

A 0.8-kb transcript was identified in liver, testis, prostate, seminal vesicle, vas deferens, and epididymis using the cDNA probe for classic cellular glutathione peroxidase. Using the probe for phospholipid hydroperoxide glutathione peroxidase, a 0.9-kb transcript was identified in the epididymis, vas deferens, prostate, seminal vesicle, and liver. In the testis, the phospholipid hydroperoxide glutathione peroxidase transcript was highly abundant and longer, measuring 1.1 kb. The phospholipid hydroperoxide glutathione peroxidase mRNA transcript was expressed in 40-, 60-, and 90-day-old rat testes, but was undetectable in testes of 10- and 20-day-old rats. Epididymal glutathione peroxidase was detected as a single 1.9-kb transcript in the caput epididymis only.

CONCLUSION(S)

Male rat reproductive tissues express at least three different isozymes of glutathione peroxidase. Phospholipid hydroperoxide glutathione peroxidase and classic cellular glutathione peroxidase are primarily found in testis, whereas epididymal glutathione peroxidase is expressed in the epididymis.

Entry of mouse embryonic germ cells into meiosis

Germ cells harvested from mouse embryonic genital ridges were mixed with disaggregated embryonic lung cells, and the reaggregates were cultured for 4-7 days. Germ cells derived from female embryos 10.5-13.5 days postcoitum (dpc) entered and progressed through meiotic prophase in vitro as in vivo, although with a 12- to 24-hr delay. If the cultures were maintained for 2-3 weeks, the germ cells developed into growing oocytes. When germ cells were taken from male embryos 10.5 and 11.5 dpc, they too entered and progressed through meiotic prophase, but germ cells from later embryos (12.5 and 13.5 dpc) developed as prospermatogonia, as in male genital ridges in vivo. When 11.5 dpc male genital ridges were disaggregated, reaggregated, and cultured in the same way as the lung reaggregates, the germ cells again entered meiotic prophase. We conclude that the male genital ridge at about 12 dpc produces a factor that inhibits entry of germ cells into meiosis, and that production of this factor is disrupted by prior disaggregation of the genital ridge. If a meiotic inducing substance is required for entry of germ cells into meiosis, it must be present in the male genital ridge as well as in the female genital ridge, and probably also in the lung.

Photoperiod-induced changes in androgen receptor expression in testes and accessory sex glands of the bank vole, Clethrionomys glareolus

Photoperiodic modulation of androgen levels and androgen receptor (AR) expression in testes and accessory sex glands were studied in a seasonally breeding rodent, the bank vole. Juvenile voles subjected to long photoperiod (20L:4D) for 6-8 wk attained sexual maturity, which was associated with a prominent increase in testicular testosterone (T) levels and weight of testes and accessory sex glands. Pubertal development in short photoperiod-treated (6L:18D for 6-8 wk) juveniles was arrested, and subsequently reproductive regression set in with a marked decrease in testicular T levels and gonadal weight. In sexually active voles, strong AR immunostaining was detected in nuclei of epithelial, smooth muscle, and stromal cells of the epididymis, prostate, and seminal vesicles. In active testes, AR was present in nuclei of Sertoli cells, peritubular cells, Leydig cells, and vascular smooth muscle cells. In juveniles, strong to moderate nuclear immunoreactivity was encountered in epithelial and stromal cells of the epididymis and prostate, whereas a weaker reaction was discerned in seminal vesicles. In juvenile testes, AR was localized to vascular smooth muscle cells, peritubular, and interstitial cells. In sexually regressed animals, nuclear staining was almost absent in accessory sex glands, whereas in testes, moderate immunostaining was retained in all other cell types except the Sertoli cells. Western blots of active and regressed testes indicated a marked photoperiod-induced down-regulation of immunodetectable AR in the regressed gonad.

Ontogeny of androgen receptor-like immunoreactivity in the reproductive tract of male Monodelphis domestica

The distribution of nuclear androgen receptor-like immunoreactivity was studied in the reproductive tract of the developing and adult gray short-tailed Brazilian opossum (Monodelphis domestica), using the well-characterized rabbit polyclonal androgen receptor antibody, PG21. Androgen receptor-like immunoreactivity was first detected on the fifth day of postnatal age, in the mesenchymal tissues of the ductus deferens, gubernaculum testis, inguinal, and scrotal areas; the urogenital sinus; and the genital tubercle. Androgen receptor-like immunoreactivity was first seen in the interstitial cells of the epididymis at 45 days of age; the testes developed androgen receptor-like immunoreactivity at 60 days of age. The epithelium of prostatic glands contained androgen receptor-like immunoreactivity only in the adult. The presence of androgen receptor-like immunoreactivity during development correlated well with the known androgen dependence of the differentiation of most reproductive organs.

m-Calpain activation/depletion is associated with androgen-induced reduction of protein kinase C and proliferation of male accessory sex organ smooth muscle cells

PURPOSE

In the guinea pig seminal vesicle smooth muscle (SVM), androgen-dependent proliferation and terminal differentiation appear to be coupled to protein kinase C (PKC). This is based on the observations that both the soluble (cytosolic) enzyme and the Triton X-100 solubilizable form of the particulate enzyme were reduced during proliferation but were androgen-resistant in the amitotic state of adults. The purpose of the present investigation was to determine if the reduction in PKC activity was linked to the translocation of the activated enzyme to acceptor sites in the Triton X-100 insoluble fraction of the cell or reflected enzyme depletion due to proteolysis by androgen-dependent activation of the u- and/or m-calpains.

MATERIALS AND METHODS

SVM was harvested from treated animals, homogenized and separated into soluble and particulate components. The particulate material was further fractionated into Triton X-100 soluble and insoluble fractions. PKC activity was determined in all fractions using radioactive ATP. Cultures of pure smooth muscle cells from both human prostate and SVM were also employed to assess the role of calpain in smooth muscle growth.

RESULTS

During androgen-induced proliferation, instead of a translocation of PKC activity to the Triton X-100 insoluble particulate fraction of the cell, PKC activity in this fraction was significantly reduced. The m-calpain was the only isoform detected in SVM. At the peak of androgen-induced DNA synthesis in pre-pubertal castrate animals, m-calpain decreased 45% whereas in proliferative resistant SVM of adult castrates the protease was not significantly affected by androgen treatment. In pure smooth muscle cultures from the SVM as well as human prostate glands calpeptin the cell permeable inhibitor of calpains produced a concentration-dependent inhibition (IC50 approximately equal to 35 microM) of cellular proliferation.

CONCLUSIONS

Given that biochemical assays of calpain quantify the residual proenzyme and that upon activation calpain is rapidly degraded, our findings indicate that m-calpain activation occurs in association with androgen-induced degradation of PKC and SMC proliferation. Thus in vitro inhibition of m-calpain activation is antiproliferative. The relative resistance of m-calpain in adult SVM may be an important component of the terminal differentiation process in normal smooth muscle.

Detection of coagulating gland renin by hybridohistochemistry

To obtain evidence of renin-synthesizing cells in the murine coagulating gland (CG), CG renin mRNA was detected by hybridohistochemistry, as well as in vitro reverse transcriptase-polymerase chain reaction (RT-PCR) in intact, castrated and testosterone-treated C57BL/6 mice. Hybridohistochemistry using paraffin sections of the kidneys and the CGs for the detection of renin mRNA was performed with digoxigenin-labelled probes. Some paraffin sections were immunohistochemically stained for renin by the peroxidase-anti-peroxidase method. Total RNA was extracted, incubated by reverse transcriptase, and amplified by PCR. In the kidneys, the immunoreactivity and the positive signals of hybridohistochemistry using an antisense probe were restricted to the same juxtaglomerular cells. In the control and at 7 days after testosterone administration to castrated mice, both renin-immunoreactivity and -hybridoreactivity were expressed by the epithelial cells in the CGs, while, in the CGs of the castrated mice and 3 days after testosterone injection of castrated animals, neither renin-immunoreactivity nor -hybridoreactivity was detected in the epithelial cells. Using RT-PCR, renin mRNA from the mice in the control and 7 days after testosterone injection of castrated was amplified, whereas, in the castrated and the 3 days after testosterone injection of castrated groups, it was not detected. The data presented here provide additional evidence that CG renin is regulated by testosterone.

Activation of androgen receptor in epidermal growth factor modulation of fetal mouse sexual differentiation

Previous studies from this laboratory indicated a role for epidermal growth factor (EGF) in androgen-dependent male sexual differentiation. The mechanism by which EGF modulates male sexual differentiation has not been determined and investigation has been made to assess the role for androgen receptor (AR) in mediating the EGF-induced effect. We report that EGF, like androgen, stabilized the Wolffian duct in the 13-day female specimen, grown in organ culture. Anti-AR, flutamide and cyproterone acetate blocked the Wolffian duct-stabilizing effect of EGF. EGF also induced cell proliferation of the fetal reproductive tract in a dose-dependent manner and a combination of physiological dosages of EGF and androgen-induced cell proliferation synergistically, suggesting an interactive effect of these two drugs. Cyproterone acetate blocked both EGF-induced normal cell proliferation and the synergistic cell proliferation induced by combination of EGF and androgen suggesting a role of AR in the effects of EGF. The role of AR was further assessed by determining the effect of EGF on AR binding directly. It was shown that EGF stimulated androgen binding activity of the male fetal reproductive tract cells significantly by increasing the number of binding sites by 3-fold with slight decrease in binding affinity. Thus, it appears that AR plays a role in mediating EGF-modulation of sexual differentiation.

Ultrastructural study of the coagulating gland of Wistar rats submitted to experimental chronic alcohol ingestion

Morphological changes of coagulating gland of Wistar rats submitted to the experimental chronic alcoholism were noted. Ultrastructurally, it was observed reduction of the granular endoplasmic reticulum cisternae and nuclei with basal position and irregular shape. The epithelial cells presented pycnotic nuclei and the mitochondrial cristae disappeared, characteristic of cellular degeneration.

Immunohistolocalization of the carbonic anhydrase isoenzymes (CA-I, CA-II, and CA-III) in the reproductive tract of male horses

OBJECTIVE

To elucidate locations of cytosolic carbonic anhydrase isoenzyme (CA-I, CA-II, and CA-III)-positive epithelial cells in equine male reproductive organs.

DESIGN

Descriptive and immunohistochemical study.

ANIMALS

4 clinically normal male horses.

PROCEDURE

The testis (seminiferous tubules, rete tubules), epididymis (initial, middle, and terminal segments), proximal and distal portions of the ductus deferens, ampulla ductus deferentis, seminal vesicle, prostate, and bulbourethral gland were excised from euthanatized horses after administration of an overdose of pentobarbital. The tissue specimens were quickly placed in fixative solution, dehydrated in ethanol, and embedded; then thin sections were cut. For immunohistochemical staining, antibodies against purified equine CA-I, CA-II, and CA-III were raised in rabbits. After examination of the specificity of each antiserum, the monospecific antisera against carbonic anhydrase isoenzymes were used to localize the isoenzymes.

RESULTS

Specific staining for CA-III was found in the Sertoli and basal cells of the ductus deferens. Most of the testicular and epididymal tissue, as well as ductus deferens, were virtually negative for the enzymes when stained with the antibody to CA-I and CA-II. In the initial segment of the epididymis, a few principal cells had intense cytoplasmic staining with anti-CA-II. In the male accessory glands, CA-I, CA-II, and CA-III were detected in the epithelial cells of the seminal vesicle, prostate, and bulbourethral gland.

CONCLUSIONS

In the equine male reproductive tract, the bicarbonate in semen originates mainly from accessory reproductive glands. All 3 isoenzymes may have central roles in the regulation of bicarbonate concentration in seminal plasm and, accordingly, regulate seminal plasma pH. Distribution of CA-III in Sertoli and basal cells of the ductus deferens suggests other specialized physiologic roles.

Immunohistochemical detection and distribution of the 1,25-dihydroxyvitamin D3 receptor in rat reproductive tissues

Vitamin D3, via its active metabolite 1,25-dihydroxyvitamin D3, plays a critical part in male and female reproduction in the rat. 1,25-Dihydroxyvitamin D3 activity is mediated by an intracellular receptor (VDR). VDR distribution in reproductive tissue has not been studied using antibodies against the receptor. We developed a polyclonal antibody against the VDR and used it to examine VDR distribution in male and female rat reproductive tissues. In rat testes, VDR epitopes were observed in seminiferous tubules, specifically in spermatogonia, Sertoli cells and spermatocytes. Spermatozoa stained faintly. Epithelial cells of the epididymis, seminal vesicles and prostate also expressed VDR epitopes. In the female rat reproductive tract, immunostaining for VDR was seen in ovarian follicles, specifically in granulosa cells. Weaker VDR immunostaining was observed in follicular thecal cells and in the ovarian stroma and germinal epithelium. Corpus luteal cells stained intensely for VDR. Epithelium of fallopian tubes and the uterus also contained VDR epitopes. Both nuclear and cytoplasmic VDR immunostaining was observed in male and female rat reproductive tissues. We conclude that the VDR is widely distributed in male and female reproductive tissues and that it is likely to mediate actions of 1,25-dihydroxyvitamin D3 in the tissues.

Identification of male epithelial cells in routine postcoital cervicovaginal smears using fluorescence in situ hybridization. Application in sexual assault and molestation

In a prospective blinded controlled study, the efficacy of fluorescence in situ hybridization (FISH) to detect non-sperm male cells verifying sexual contact was examined. Cervicovaginal smears (CVS) from 40 women with reported post-coital intervals were examined for sperm by cytology and for sperm and non-sperm male cells by FISH using X and Y chromosome specific DNA probes. Fluorescence in situ hybridization identified sperm and/or non-sperm male cells in all specimens from women with positive coital histories, including when the partner had a vasectomy. Male cells were also detectable by FISH in CVS up to 3 weeks after coitus. In comparison, cytology identified sperm in 41% of the positive coital history cases, and none beyond 2 weeks. Fluorescence in situ hybridization is highly sensitive and specific in detecting male cells, and can be performed rapidly on routine CVS. Application of this technique can provide new and additional evidence of sexual contact when current tests are inconclusive.

Induction of estrogen receptor and cell division in genital tracts of male mice by neonatal exposure to diethylstilbestrol

Estrogen receptor (ER) and ER mRNA expression and cell division induced by neonatal diethylstilbestrol (DES) exposure in male C57BL/Tw mouse genital organs were studied using immunohistochemistry, in situ hybridization, and cell counting at metaphase. A single injection of 3 micrograms DES on the day of birth induced ER in both epithelial (E) and stromal (S) cells of the epididymis and the seminal vesicles, in E cells of the ductus deferens, and in S cells of the ductus efferens and the anterior prostate 24 h after the injection. After 5 daily injections of DES, ER was induced in S cells of the ventral prostrate at 5 days of age. The staining intensity of ER increased in E cells of the epididymis and the ductus efferens at 5 days. A single injection of DES induced ER mRNA in both E and S cells of the ductus efferens, the caput epididymis, and the ductus deferens 4 to 12 h after injection of the newborn mice. A single injection of DES stimulated cell division of both E and S cells in the ductus deferens and the epididymis; cell division of S cells of the ductus efferens, the anterior prostate, and the urethra was stimulated 24 h after the injection. After 5 daily injections of DES, cell division was stimulated significantly in E and S cells of the epididymis, the ductus deferens, and the ventral prostate, and in S cells of the seminal vesicle at 5 days. At 30 days of age, mitotic rates were significantly higher in E cells of the seminal vesicles and the epididymides of mice given 5 daily injections of DES.(ABSTRACT TRUNCATED AT 250 WORDS)

Anopheles culicifacies: effects of age on the male reproductive system and mating ability of virgin adult mosquitoes

Under controlled laboratory conditions of 28-30 degrees C and 16:8 L:D photoperiod, an attempt was made to develop an age-grading technique for Anopheles culicifacies males. Mating activity was maximal when females were 5-12 days old males were 5-7 days old. The numbers of total and mature spermatocysts declined significantly with age, and the proportion of the testes occupied by the sperm reservoir increased as virgin males grew older. Mating resulted in the loss of spermatozoa and accessory gland substance from the reproductive system. Loss of mating ability of older virgin males seemed to be age-related, because the reproductive system contained ample supplies of accessory gland substance and spermatozoa. Morphological changes of the reproductive system, due to mating and age, were used to infer the age and reproductive history of unknown males in a laboratory evaluation.

Localization of the glucocorticoid receptor in testis and accessory sexual organs of male rat

Localization of glucocorticoid receptor-like immunoreactivity (GR-LI) was studied in adult rat testis, epididymis, ejaculatory duct, seminal vesicle and prostate by light and electron microscopic immunocytochemistry. In the interstitium of the testis GR-LI was seen in the nuclei of Leydig cells, macrophages, fibroblasts, smooth muscle cells and endothelial cells of blood vessels. Furthermore, GR-LI was observed in zygotene and early pachytene primary spermatocytes of some seminiferous tubules during stages XIII-XIV and I-III of the spermatogenic cycle. Other spermatogenic cells and Sertoli cells were devoid of staining. GR-LI was also found in peritubular myoid cells, fibroblasts and basal cells of the epididymis, vas deferens and prostate. Localization of GR-LI in primary spermatocytes and Leydig cells suggests that glucocorticoids directly affect spermato- and steroidogenesis in the testis. The absence of GR-LI from functional, stromal cells of the male accessory sexual organs suggests that they are not targets for glucocorticoid hormones.

1,25(OH)2 vitamin D3 binding sites in male sex organs of the Siberian hamster (Phodopus sungorus). An autoradiographic study

Using autoradiography, binding sites for 1,25(OH)2 vitamin D3 are found in certain genital organs of male Siberian hamsters (Phodopus sungorus), in particular in basal epithelial cells and fibroblasts of the lamina propria of prostate glands. Scattered labeled cells are also present in the epithelium of coagulation and urethral glands. In contrast to the findings in mice, under the conditions of the experiment, 1,25(OH)2 vitamin D3 binding sites are not recognizable in other accessory sex glands and gonads. The frequency of basal epithelial cells with [3H]1,25(OH)2 vitamin D3 nuclear binding is higher in regressed dorsal prostate glands of animals living in short photoperiods. The data suggest that 1,25(OH)2 vitamin D3 may promote proliferation and differentiation in basal epithelial cells, modulated by the seasonal and functional status of the animal.

Progestagen nuclear binding sites in the male genital tract of the mouse, studied by autoradiography

Autoradiograms were prepared after injection of 125I progestagen (sp. act. 2200 Ci/mmol) to prepubertal and young adult mice. Nuclear concentration of radioactivity was found in smooth muscle cells at the beginning and the end of the deferent duct and in fibroblasts around the fusion of the deferent duct with the urethra. Nuclear labeling was enhanced in adult animals pretreated with oestradiol-valerate. In prepubertal mice nuclear labeling was more abundant than in adult mice and found in all smooth muscle cells of the deferent duct. No nuclear labeling was observed in other accessory sex organs. Nuclear labeling was prevented by injection of excess of unlabeled R5020. The presence of progestin receptors in smooth muscle cells of the deferent duct suggests a regulatory effect of progestin on contractions in analogy to progestin effects on oviductal and uteral smooth muscle cells. The presence of nuclear progestin receptors in the periurethral region may indicate an involvement of progestins in the etiology and regulation of benign prostate hyperplasia.

Adrenergic stimulation of diacylglycerol production in genital tract smooth muscle myocytes

Diacylglycerol (DAG) production has not been reported in previous studies that have characterized inositol phosphate production during alpha-1 adrenergic receptor signal transduction in the DDT1 MF-2 genital tract myocytes. The current study sought to measure norepinephrine (NE)-stimulated DAG production in these transformed myocytes utilizing thin layer chromatography. DAG production was characterized as an alpha-1 adrenergic mediated event utilizing subtype specific adrenergic agonist and antagonists. DAG production occurred in response to physiologic concentration of NE, was apparent by 30 s and was significantly increased by 2 min. Maximal DAG production was unaffected by pretreatment of the myocytes for 96 h with testosterone, which has previously been shown to induce a doubling of alpha-1 adrenergic receptors in these cells. In contrast, testosterone pretreatment did result in a shift of the dose-response curve resulting in a significantly lower EC50 for NE in the treated cells compared to control myocytes. In conclusion, these studies have confirmed that DAG production occurs as a component of alpha-1 adrenergic signal transduction in the DDT1 MF-2 myocytes; transduction events that were modulated by testosterone resulting in increased agonist sensitivity.

Multiple cell interactions are required for fate specification during male spicule development in Caenorhabditis elegans

The B blast cell divides postembryonically in C. elegans males to produce 47 progeny that include all of the cells of the copulatory spicules. During the early development of the B lineage, the anterior daughter of B, B.a, generates eight cells. These cells migrate to form four pairs of cells that flank the developing cloaca (ventral, dorsal, and two identical lateral pairs). For each pair, the more anterior cell produces a distinct lineage ('anterior fate') from the posterior cell ('posterior fate'). For the ventral and dorsal pairs, either cell can migrate to the anterior position and produce the anterior lineage, and the other cell migrates posterior and produces the posterior lineage (Sulston and Horvitz, 1977, Dev. Biol. 56, 110–156). The migration is variable, although the resultant fate pattern is invariant. In the two lateral pairs, both the migration and fate pattern are invariant. Using a laser microbeam to selectively ablate neighboring cells we have found that the cells of the lateral pair also respond to positional cues. For all four pairs other male-specific blast cells provide extracellular cues. In general, F and U promote anterior fates, Y promotes some posterior fates, and the B.a progeny promote posterior fates. Several of these cues are redundant. By ablating combinations of cells we have deduced how these signals may act in concert to specify the fates of the B.a progeny. We propose that fate specification in these pairs depends on three general classes of extracellular cues: positional cues, modulators of positional cues, and lateral signals. The B lineage thus provides an opportunity to study with single cell resolution the integration of multiple intercellular signals.

Cell type-specific gene expression in the Drosophila melanogaster male accessory gland

The accessory gland of the male Drosophila melanogaster plays a vital role in reproduction. This secretory organ synthesizes products that are transferred to the female and are necessary to elicit the proper physiological and behavioral responses in the female. The accessory gland is composed of two morphologically distinct secretory cell types, the main cells and the secondary cells. Previous studies identified some genes expressed in main cells or in all accessory gland cells. In this paper we use P-element mediated enhancer traps to examine gene expression in the accessory gland. We show that, in addition to genes expressed in main cells only or in all accessory gland secretory cells, there are genes expressed specifically in secondary cells. Each cell type is uniform in the expression of its genes. Our results demonstrate that the two cell types are not only morphologically distinct but also biochemically distinct. We also show that the two cell types differ in their regulation of gene expression in response to mating activity.

Protein kinases and the androgen-induced proliferation of accessory sex organ smooth muscle

The possible role of second messenger systems in androgen-dependent smooth muscle proliferation was investigated. Focusing on the hormone-sensitive guinea pig seminal vesicle, we analyzed changes in protein kinase C (PKC) and cAMP-dependent type I and II protein kinases during the androgen-dependent smooth muscle proliferation of puberty, as well as in the transition to the nonproliferative state of the adult. The androgenic sensitivity of the cAMP-dependent type I and II protein kinases and the cAMP-dependent phosphorylations of soluble muscle proteins did not correlate with the qualitative change in the androgenic sensitivity of the prepubertal vs. adult animals. In contrast to the cAMP-dependent protein kinases, regulation of the soluble and particulate forms of PKC corresponded to the androgen-induced smooth muscle proliferation. That is, in the seminal vesicle muscle of prepubertal castrated animals, androgen treatment reduced both the soluble and particulate forms of PKC during the increase in smooth muscle DNA synthesis, and in adult seminal vesicle smooth muscle, which was resistant to androgen-induced proliferation, both forms of the enzyme were resistant to androgenic stimulation. It is concluded that PKC may be a component of an autocrine mitogenic mechanism involved in the coupling and uncoupling of androgen-induced smooth muscle proliferation.

Role of epithelial-mesenchymal interactions in the differentiation and spatial organization of visceral smooth muscle

Uterine mesenchyme from newborn (0-day) rats was grown in association with epithelia from the adult cornea, urinary bladder, oesophagus, mammary gland, 1-day skin, and 1-day uterus. Following 1 month of growth, the differentiation of uterine mesenchyme into actin-positive smooth muscle cells was assessed immunocytochemically with antibodies to smooth muscle actin. Whereas grafts of uterine mesenchyme produced only small amounts of myometrium, all types of epithelia induced extensive myometrial differentiation in the uterine mesenchyme, which indicates that this effect is non-specific. The role of cell-cell interactions in the morphological patterning of smooth muscle layers was assessed by analysing tissue recombinants composed of adult prostatic epithelium (PRE) plus mesenchyme of the urogenital sinus (UGM), or seminal vesicle (SVM), or adult bladder epithelium (BLE) plus UGM or SVM. Prostatic ducts developed in all of these tissue recombinants (UGM + BLE, SVM + BLE, UGM + PRE and SVM + PRE). When UGM was used (UGM + PRE and UGM + BLE recombinants), actin-positive smooth muscle cells became organized into thin sheaths resembling the prostatic pattern. Conversely, when SVM was grown in association with PRE or BLE, the induced prostatic ducts were surrounded by thick layers of smooth muscle cells exhibiting the seminal vesicle pattern of organization. Smooth muscle cells were unorganized in grafts of SVM or UGM alone. These observations suggest that in male urogenital glands the mesenchyme dictates the spatial organization of the smooth muscle layers.(ABSTRACT TRUNCATED AT 250 WORDS)

HOX-4 genes and the morphogenesis of mammalian genitalia

We examined the temporal and spatial expression patterns of the homeo box HOX-4 complex genes during the morphogenesis of the genitalia of mice. The results show that only those Hox-4 genes that are expressed very posteriorly in the trunk, or very distally in the limbs, seem to be involved in the patterning of the genital tubercle. This is consistent with the idea of "temporal colinearity", which suggests that the very last structure to require patterning during vertebrate development will express Hox genes located at the 5' extremity of the HOX complexes. We also show that genital tubercle mesenchyme can respecify pattern in the chicken wing bud. This finding reinforces the concept of the uniformity in the patterning mechanisms along the various axes of the body.

Role of epithelial cells of the male excurrent duct system of the rat in the endocytosis or secretion of sulfated glycoprotein-2 (clusterin)

The localization of sulfated glycoprotein-2 (clusterin; SGP-2) was investigated in the rete testis, efferent ducts, and epididymis of the rat using light (LM) and electron (EM) microscope immunocytochemistry. At the LM level, the epithelial cells of the rete testis and efferent ducts demonstrated an intense immunoperoxidase reaction over their apical and supranuclear regions, and sperm in the lumen of the efferent ducts were unreactive. In the EM, gold particles were found exclusively over the endocytic apparatus of these cells. In the proximal area of the epididymal initial segment, an insignificant immunostaining of epithelial cells and sperm was observed. However, the distal area of the initial segment showed a moderate staining over the epithelial principal cells and sperm, while in the intermediate zone of the epididymis a stronger reaction was observed over these cells. The strongest immunoperoxidase reaction was noted in the caput epididymidis, where it formed a distinct mottled pattern. Thus, while some principal cells were intensely stained, others were moderately or weakly stained; a few were completely unreactive. In the corpus and cauda epididymidis, the staining pattern was similar but not as intense. In the EM, only the secretory apparatus of these cells was found to be immunolabeled with gold particles. Sperm in the lumen of these different regions were also labeled. The epithelial clear cells were unreactive throughout the epididymis. Northern blot analysis substantiated these results and showed the presence of highest levels of SGP-2 mRNA in the caput epididymidis, especially in its proximal area, whereas increasingly lower levels were found in the corpus and cauda epididymidis. In summary, these results suggest that testicular SGP-2 dissociates from the sperm during passage through the rete testis and efferent ducts, where it is endocytosed by the epithelial cells lining these regions. In the epididymis, it is replaced by an epididymal SGP-2 that is secreted by the epithelial principal cells of the epididymis. Furthermore, in the epididymis, the principal cells appear to be in different functional states with respect to the secretion of epididymal SGP-2 within a given region of the duct as well as along the epididymal duct.

Histochemical reactivity of the Geodia cydonium agglutinin (GCA) in human tissues

We applied a peroxidase-antiperoxidase technique to study the distribution pattern and binding characteristics of the lectin from the marine sponge Geodia cydonium (Geodia cydonium agglutinin; GCA) in various human tissues. This lectin has been shown to possess a broad reactivity, but there was a distinct distribution of binding sites within the different organs. In the histochemical system GCA displayed no blood group specificity and labeled red blood cells, the vascular endothelium, and epithelial cells showing blood group antigen expression independent of the ABH blood group status. However, inhibition of GCA reactivity by simple sugars and complex carbohydrates demonstrated tissue-specific differences of lectin binding related to the ABH blood group status of the tissue and revealed information on the structural requirements of the histological lectin binding site. Tissues that totally lacked blood group antigens or that expressed only the H-antigen disclosed a GCA reactivity which was completely inhibited by lactose. In contrast, tissues that expressed blood group A- or blood group B-antigen exhibited a lactose-resistant lectin binding which was inhibited only by water-soluble blood group substance A from peptone A and by bovine glycophorin but not by other complex carbohydrates, including human glycophorin and human asialoglycophorin. Competitive inhibition studies in situ revealed that GCA binding was not inhibited by blood group type I/II carbohydrate sequence-specific lectins or by lectins with other sugar specificities. Inhibition by lactose of GCA binding to some histological sites indicates that the binding site consists of a beta-linked galactose-containing disaccharide. However, periodate oxidation of tissue sections had no effect on lectin binding, pointing to a subterminal location of the relevant sequence. The results obtained from inhibition studies with simple saccharides and complex carbohydrates in relation to the expression of ABH blood group antigens suggest a complex lectin combining site(s) in histological specimens. The lectin may possess either one binding site with a range of affinities for different carbohydrates (besides beta-linked disaccharides the GCA binding site accommodates to carbohydrate determinants carrying the blood group A or blood group B determinant), or may possess two different binding sites. Besides an acceptor site for beta-linked disaccharides, an additional binding site may exist accommodating to extended carbohydrate sequences related to A or B blood group structures. In conclusion, GCA represents a blood group-nonspecific lectin whose binding affinities are determined by the ABH blood group status of the tissue.

Histomorphologic observations for cynomolgus monkeys after subchronic subcutaneous injection of recombinant human interleukin-4

Recombinant human interleukin-4 (rhuIL-4) is a candidate for the treatment of refractory cancer based on its potential to enhance the function of the immune system. Total daily dosages of 0 (placebo control), 1, 5, or 25 micrograms/kg of rhuIL-4 were given as divided (b.i.d.) subcutaneous dosages to male and female cynomolgus monkeys (5/sex/group) for 1 month followed by a 2-week recovery. Histomorphologic evaluation of 3/sex/group at 1 month revealed vascular lesions, granulocytic hyperplasia, and seminiferous tubular atrophy attributed to treatment with rhuIL-4. Dosage-dependent proliferative and inflammatory vascular lesions with eosinophil infiltration affected principally the arterial tree. After 2 weeks of recovery, these lesions, including chronic endarteritis and chronic and/or obliterative arteritis, occurred with an overall lower incidence, and were not observed for monkeys from the 1.0 micrograms/kg/day group. Granulocytic hyperplasia in bone marrow observed for monkeys from all groups given rhuIL-4 at 1 month was not present after 2 weeks of recovery. Seminiferous tubular atrophy was observed for monkeys from the 5 and 25 micrograms/kg/day groups at 1 month and after 2 weeks of recovery.