Dietary intervention with narrow-leaved cattail rhizome flour (Typha angustifolia L.) prevents intestinal inflammation in the trinitrobenzenesulphonic acid model of rat colitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphological investigations of the surface epithelium of ductuli efferentes of black isogenic mice (Mus musculus)

Morphological investigations of the epithelial cell types that line the ductuli efferentes (DE) of black isogenic mice confirm absorption of the luminal fluid phase by endocytosis as the main function of ductuli efferentes (DE) in this species. :Furthermore, all the histochemical and ultrastructural observations on the DE epithelial histoarchitecture indicate other cellular functions such as exocytosis and probably secretion: including an aprocrine secretory process.

Differential proliferative response of the ventral prostate and seminal vesicle to testosterone replacement

We have investigated epithelial cell proliferation and the rate of glandular recovery of the ventral prostate (VP) and seminal vesicle (SV) promoted by testosterone replacement (TR) in castration-induced regressed glands. Adult male Wistar rats were castrated and, after 21 days, they were treated with testosterone propionate (4 mg/kg/day). Intact (CT) and castrated rats without TR (CS) were also analysed. VP and SV were processed for histochemistry, morphometric-stereological analysis and immunocytochemistry to determine the PCNA index (PI). After 10 days of TR, the VP weight reached similar to 72% of the CT values, while the SV weight exceeded similar to 17% of the CT values. By the third day of TR, VP and SV presented a mean P1 of 34% and 94% for distal region and 14% and 22% for proximal region, respectively. SV also had more luminal cells PCNA-positive than VP, mainly in the distal region. The PI values fell on days 5, 7 and 10, but were still higher than CT. These findings indicate that epithelial cells from involuted SV are more responsive to TR than those from VP when Stimulated to proliferate and replace the luminal cell population, suggesting a different mechanism regulating cell proliferation in response to androgenic stimuli. (c) 2006 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.

Long-term effects of developmental exposure to di-n-butyl-phthalate (DBP) on rat prostate: Proliferative and inflammatory disorders and a possible role of androgens

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Functional and Morphological Reproductive Aspects in Male Rats Exposed to Di-n-Butyl Phthalate (DBP) in Utero and During Lactation

The potential adverse reproductive effects, with emphasis on the epididymis, of in utero and lactational exposure to 100 mg/kg/d di-n-butyl phthalate (DBP) in adult male rat offspring were investigated. The fetal testis histopathology was also determined. The selected endpoints included reproductive organ weights, sperm motility and morphology, sperm epididymal transit time, sperm quantity in the testis and epididymis, hormonal status, fetal testis and epididymal histopathology and stereology, and androgen receptor (AR), aquaporin 9 (AQP9), and Ki-67 immunoreactivities. Pregnant females were divided into two groups: control (C) and treated (T). The treated females received DBP (100 mg/kg/d, by gavage) from gestation day (GD) 12 to postnatal day (PND) 21, while control dams received the vehicle. Some pregnant dams were killed by decapitation on GD20, and testes from male fetuses were collected for histopathogy. Male rats from other dams were killed at PND 90. Fetal testes from treated group showed Leydig-cell clusters, presence of multinucleated germinative cells, and increase of the interstitial component. Testosterone levels and reproductive organ weights were similar between the treated and control adult groups. DBP treatment did not markedly affect relative proportions of epithelial, stromal, or luminal compartments in the epididymis; sperm counts in the testis and epididymis; sperm transit time; or sperm morphology and motility in adult rats. The AR and AQP9 immunoreactivities and proliferation index were similar for the two groups. These results showed that fetal testes were affected by DBP as evidenced by testicular histopathologic alterations, but reproductive parameters and epididymal structure/function were not significantly altered in the adult animals exposed to 100 mg/kg DBP in utero and during lactation.

Unique Derived Features in Spermiogenesis and Sperm Morphology Supporting a Close Relationship between the Species of Hollandichthys and Rachoviscus (Characiformes: Characidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Oral exposure to methylmercury modifies the prostatic microenvironment in adult rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphological and enzymatic analysis of the midgut of Anopheles darlingi during blood digestion

The midgut of adult female Anopheles darlingi is comprised of narrow anterior and dilated posterior regions, with a single layered epithelium composed by cuboidal digestive cells. Densely packed apical microvilli and an intricate basal labyrinth characterize each cell pole. Before blood feeding, apical cytoplasm contains numerous round granules and whorled profiles of rough endoplasmic reticulum. Engorgement causes a great distension of midgut. This provokes the flattening of digestive cells and their nuclei. Simultaneously, apical granules disappear, the whorls of endoplasmic reticulum disassemble and 3 h post bloodmeal (PBM), nucleoli enlarge manyfold. An intense absorptive process takes place during the first 24h PBM, with the formation of large glycogen inclusions, which persist after the end of the digestive process. Endoproteases activities are induced after bloodmeal and attain their maximum values between 10 and 36 h PBM. At least two different aminopeptidases seem to participate in the digestive process, with their maximum activity values at 36 and 48 h PBM, respectively. Coarse electrondense aggregates, possibly debris from digested erythrocytes, begin to appear on the luminal face of the peritrophic membrane from 18 h PBM and persist during all the digestive process, and are excreted at its end. We suggest that these aggregates could contain some kind of insoluble form of haem, in order of neutralize its toxicity. (c) 2005 Elsevier Ltd. All rights reserved.

Programmed cell death in the larval salivary glands of Apis mellifera (Hymenoptera, Apidae)

The morphological and histochemical features of degeneration in honeybee (Apis mellifera) salivary glands were investigated in 5th instar larvae and in the pre-pupal period. The distribution and activity patterns of acid phosphatase enzyme were also analysed. As a routine, the larval salivary glands were fixed and processed for light microscopy and transmission electron microscopy. Tissue sections were subsequently stained with haematoxylin-eosin, bromophenol blue, silver, or a variant of the critical electrolyte concentration (CEC) method. Ultrathin sections were contrasted with uranyl acetate and lead citrate. Glands were processed for the histochemical and cytochemical localization of acid phosphatase, as well as biochemical assay to detect its activity pattern. Acid phosphatase activity was histochemically detected in all the salivary glands analysed. The cytochemical results showed acid phosphatase in vesicles, Golgi apparatus and lysosomes during the secretory phase and, additionally, in autophagic structures and luminal secretion during the degenerative phase. These findings were in agreement with the biochemical assay. At the end of the 5th instar, the glandular cells had a vacuolated cytoplasm and pyknotic nuclei, and epithelial cells were shed into the glandular lumen. The transition phase from the 5th instar to the pre-pupal period was characterized by intense vacuolation of the basal cytoplasm and release of parts of the cytoplasm into the lumen by apical blebbing; these blebs contained cytoplasmic RNA, rough endoplasmic reticule and, occasionally, nuclear material. In the pre-pupal phase, the glandular epithelium showed progressive degeneration so that at the end of this phase only nuclei and remnants of the cytoplasm were observed. The nuclei were pyknotic, with peripheral chromatin and blebs. The gland remained in the haemolymph and was recycled during metamorphosis. The programmed cell death in this gland represented a morphological form intermediate between apoptosis and autophagy.

Differential coronary resistance microvessel remodeling between type 1 and type 2 diabetic mice: Impact of exercise training

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Postnatal growth of the ventral prostate in Wistar rats: A stereological and morphometrical study

Morphological and stereological analyses were used to characterize the growth kinetics of the Wistar rat ventral prostate (VP). Volume density and absolute volume of the epithelium, lumen, smooth muscle cells (SMCs), and nonmuscular stroma were determined by stereology and paired with plasma testosterone levels and different morphometric measurements. The VP shows an initial growth within the first 3 weeks, a resting phase, and the puberal growth. The puberal growth was coincident with the raise in plasma testosterone. Lumen formation occurred within the 3 postnatal weeks. After an expected increase during puberty, the lumen showed a further increase at the 12th week. The volume density of the nonmuscular stroma and of the SMCs decreased slowly postnatally. Absolute volume of the luminal compartment showed three phases of growth (weeks 1-3, 6-9, and 11-12). on the other hand, the increase in the absolute volume of the epithelium was steady up to the 8th week and then showed a marked increase up the 10th week. The increase in epithelial volume was characterized morphologically by the presence of epithelial infoldings and sprouts. The growth of the epithelium showed a 2-week delay as compared to the lumen and occurred only until the 10th week. The epithelial height was variable but could be related to the synthetic activity of the epithelium. In conclusion, the postnatal growth of the VP results from a combination of epithelial proliferation/differentiation and synthesis/accumulation of the secretory products in the lumen.

Inhibition of 5-alpha-reductase activity induces stromal remodeling and smooth muscle de-differentiation in adult gerbil ventral prostate

Prostatic differentiation during embryogenesis and its further homeostatic state maintenance during adult life depend on androgens. Dihydrotestosterone, which is synthesized from testosterone by 5alpha-reductase (5alpha-r), is the active molecule triggering androgen action within the prostate. In the present work, we examined the effects of 5alpha-reductase inhibition by finasteride in the ventral prostate (VP) of the adult gerbil, employing histochemical and electron microscopy techniques to demonstrate the morphological and organizational changes of the organ. After 10 days of finasteride treatment at a dose of 100 mg/kg/day, the prostatic complex (VP and dorsolateral prostate) absolute weight was reduced to about 18%. The epithelial cells became short and cuboidal, with less secretory blebs and reduced acid phosphatase activity. The luminal sectional area diminished, suggestive of decreased secretory activity. The stromal/epithelial ratio increased, the stroma becoming thicker but less cellular. There was a striking accumulation of collagen fibrils, which was accompanied by an increase in deposits of amorphous granular material adjacent to the basal lamina and in the clefts between smooth muscle cells (SMC). Additionally, the periacinar smooth muscle became loosely packed. Some SMC were atrophic and showed a denser array of the cytoskeleton, whereas other SMC had a highly irregular outline with numerous spine-like projections. The present data indicate that 5alpha-r inhibition causes epithelial and stromal changes by affecting intra-prostatic hormone levels. These alterations are probably the result of an imbalance of the homeostatic interaction between the epithelium and the underlying stroma.

Microscopic comparative study of the exposure effects of testosterone cypionate and ethinylestradiol during prenatal life on the prostatic tissue of adult gerbils

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Lobe identity in the Mongolian gerbil prostatic complex: A new rodent model for prostate study

Knowledge of structural and physiological differences among the prostatic lobes (PL) is the basis for development of experimental studies in traditional laboratory rodents. Although Mongolian gerbil reproductive organs have been increasingly investigated, its prostate structure is far from being properly known, and investigations of this organ focused on the ventral lobe (VL). Thus, the present study provides a thorough morphological description of prostatic complex in the male adult gerbil on the basis of topographic, histological, and ultrastructural analysis and ductal branching. Like other rodents, four pairs of PL were observed. However, in contrast to the rat and mouse, the VL is the least voluminous component and the dorsolateral lobe (DLL) is the most prominent and spatially isolated from remaining PL. The occurrence of a dorsal lobe (DL), hidden between bladder and insertion of seminal vesicles, has not been mentioned in previous reports with Mongolian gerbil. Collagenase digestion followed by microdissection revealed that, except for DL, which has a tubularacinar organization, all PL exhibit tubular organization and variable ductal branching. Distinct histological and ultrastructural features such as secretory epithelium, aspect of luminal secretion and stromal organization are reported for each PL and are confirmed by morphometric and stereological methods. Histological sections showed at least three intralobar segments in VL and DL. Ultrastructural analysis evidenced that, although luminal epithelial cells of PL share typical features of exocrine secretory cells, there are striking lobe phenotypical variations. Both merocrine and apocrine pathways are observed in variable rates in all PL, with the predominance of the former in the DLL and the latter in the CG. The morphological observations presented herein point to distinct structural identities for each PL, which probably reflects,specific functional compromise of seminal fluid secretion. These data also point to the gerbil as a good model for investigations concerning the regulation of prostate development and homeostasis, mainly with regard to the dorsal and dorsolateral PL.

Morphological and morphometric characteristics of the epididymis in the Neotropical bats Eumops glaucinus and Molossus molossus (Chiroptera: Molossidae).

The ability of certain species of bats to store viable spermatozoa in the cauda epididymis, for periods of many months beyond the end of spermatogenesis was first recognized over a century ago. However, information about the bat epididymis is still scarce or absent. Thus, this study aimed to characterize and to compare morphologically and morphometrically the regional histology of the epididymis of Eumops glaucinus and Molossus molossus (Chiroptera: Molossidae). Histologically, the epididymis of both species was subdivided into 4 segments: initial segment, caput, corpus and cauda. In comparing the two species, it was observed that the tubular and luminal diameters and percentage of interstitial tissue showed significant differences in all segments. The epithelial height, in both, is greater in the initial segment with a decrease until the cauda epididymis. In relation to the luminal diameter, both species showed a gradual increase from the initial segment to the cauda. The percentage of epithelium, lumen and interstitial tissue varied between both, sometimes M. molossus showing a significantly higher percentage, and other times, E. glaucinus. In both species, the principal cell was the most abundant (> 77%), followed by basal cells at approximately 13% and apical cells at 4% in all segments. Spermatozoa were observed in greater amounts in corpus and cauda epididymis segments. In summary, ours results show that, despite that the species analyzed belong to different genera and have different breeding cycles, the epididymis exhibits similarities in the two species and morphometric and composition differences compared to the majority of mammals.