Identification of “Huoshan shihu” Fengdou: Comparative authentication of the Daodi herb Dendrobium huoshanense and its related species by macroscopic and microscopic features

“Huoshan shihu,” derived from Dendrobium huoshanense, is a well‐known, valuable, and rare Daodi herb. Because of its higher price and scarce resources, its related species D. officinale and D. moniliforme are usually presented as “Huoshan shihu” for sale. Fengdou, the processed form of D. huoshanense, its identification is particularly important. To effectively identify Fengdou of D. huoshanense and protect the Daodi herb, the morphological and microscopic characteristics of the stems of three Dendrobium species were examined. The results showed that macroscopic and microscopic features helpful for identification of the three species were the total lengths and internode numbers of stems, diameter and length of each internode, number of vascular bundles, and presence or absence of silica masses. The key features useful for distinguishing between D. huoshanense and its related species, and also between their Fengdou, were the stem lengths and the trends of change in diameter in different internodes. The results of the study indicated that a combination of macroscopic and microscopic identification techniques might conveniently and effectively be applied for identification of Dendrobium species. “Longtou Fengwei” is the main feature of the Daodi herb “Huoshan shihu,” (D. huoshanense Fengdou) and reflects the wisdom behind the protection of Daodi herbs in ancient times.     

Microscopic analysis of “iron spot” on blue‐and‐white porcelain from Jingdezhen imperial kiln in early Ming dynasty (14th–15th century)

“Sumali,” as an imported cobalt ore from overseas, was a sort of precious and valuable pigment used for imperial kilns only, which produces characteristic “iron spot” to blue‐and‐white porcelain in early Ming Dynasty (A.D. 14th–15th century). Although there were some old studies on it, the morphology and formation of iron spot has not been fully investigated and understood. Therefore, five selected samples with typical spot from Jingdezhen imperial kiln in Ming Yongle periods (A.D. 1403–1424) were analyzed by various microscopic analysis including 3D digital microscope, SEM‐EDS and EPMA. According to SEM images, samples can be divided into three groups: un‐reflected “iron spot” without crystals, un‐reflected “iron spot” with crystals and reflected “iron spot” with crystals. Furthermore, 3D micro‐images revealed that “iron spots” separate out dendritic or snow‐shaped crystals of iron only on and parallel to the surface of glaze for which “iron spot” show strong metallic luster. Combining with microscopic observation and microanalysis on crystallization and non‐crystallization areas, it indicates that firing oxygen concentration is the ultimate causation of forming reflective iron spot which has a shallower distribution below the surface and limits crystals growing down. More details about characters of “iron spot” used “Sumali” were found and provided new clues to coloration, formation mechanism and porcelain producing technology of imperial kiln from 14th to 15th centuries of China.     

Authenticating and distinguishing the eight species of traditional Tibetan medicine “Meiduoluomi” by microscopic technique

Because of the morphological and macroscopic similarity, many species of Erigeron and Aster (Asteraceae) are confusable and usually used under the same name “Meiduoluomi” in traditional Tibetan medicine (TTM). To find an easy, quick, and reliable method to authenticate and distinguish the eight main medicinal plants of these species, the light microscope was used to reveal the morphoanatomic details. The fixed, sectioned, and stained plant materials and epidermis materials were studied by microscopic techniques. The results of the microscopic features are systematically described and illustrated, and comparison parameters are presented. Furthermore, a key to the eight species of “Meiduoluomi” was constructed. Microscopy can be unambiguously used to authenticate and distinguish the eight main species of TTM “Meiduoluomi.” Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.     

A comparative study of mud‐like and coralliform calcium carbonate gallbladder stones

To gain insight to underlying mechanism of the formation of calcium carbonate (CaCO₃) gallbladder stones, we did comparative study of stones with mud appearance and those with coralliform appearance. A total of 93 gallbladder stones with mud appearance and 50 stones with coralliform appearance were analyzed. The appearance, color, texture, and the detection of Clonorchis sinensis eggs by microscopic examination were compared between the two groups. Then, the material compositions of stones were analyzed using Fourier Transform Infrared spectroscopy and the spectrogram characteristics were compared. Moreover, microstructure characteristics of the two kinds of stones were observed and compared with Scanning Electron Microscopy. Mud‐like gallbladder stones were mainly earthy yellow or brown with brittle or soft texture, while coralliform stones were mainly black with extremely hard texture, the differences between the two groups was significant (p < .05). The analytic results of FTIR spectroscopy showed that 95.7% (89/93) of the mud‐like gallbladder stones were CaCO₃ stones, and mainly aragonite; while all of the coralliform stones were CaCO₃ stones, and mainly calcite (p < .05). Meanwhile, microscopic examination indicated that the detection rate of Clonorchis sinensis eggs in mud‐like CaCO₃ stones was lower than that in coralliform CaCO₃ stones (p < .05), and that in aragonite CaCO₃ stones was lower than that in calcite CaCO₃ stones(p < .05). Mud‐like CaCO₃ stones mainly happened to patients with cystic duct obstruction. Clonorchis sinensis infection was mainly associated with coralliform (calcite) CaCO₃ stones. Cystic duct obstruction was mainly associated with mud‐like (aragonite) CaCO₃ stones.     

A simple “hands‐off” apparatus to inflate concealed soft parts of the genitalia of small insect specimens

We describe a simple, effective and relatively cheap instrument for the inflation of soft parts of insect genitalia, particularly the vesica (endophallus) of small male lepidopteran specimens. It can also be applied in female genitalia and for the hyperextension of postabdominal segments of the telescoping type. A fine glass capillary is mounted on a self‐constructed micromanipulator system with capillary holder, moveably placed aside a microscope. The micromanipulator is constructed from the x‐ and y‐pinions of a discarded microscope table and the z‐pinion of a discarded microscope. Preparation is carried out as usual on a microscopic slide. The inflatable soft parts are pushed out mechanically and then fully inflated and subsequently hardened by pumping absolute alcohol with a medical syringe via a flexible PVC tube, the capillary holder and the glass capillary into the phallus. With affordable effort, our “hands‐off”apparatus might considerably ease preparation. Microsc. Res. Tech. 76:258–262, 2013. © 2013 Wiley Periodicals, Inc.     

A mixed microscopic method for differentiating seven species of “Bixie”‐related Chinese Materia Medica

Confusion in the species associated with the name of “Bixie” in Chinese Materia Medica began centuries ago. In recent decades, diverse medicinal plants from the genera Dioscorea and Smilax, and even minor species from the genus Heterosmilax, have been documented under the name Bixie or a very similar name as folk medicines in different areas of China. However, the traditional efficacies and chemical profiles of these herbs are not exactly the same and even vary wildly. Comprehensive authentication of multiple Bixie herbs has not yet been attempted. To differentiate and ensure the correct use of these Bixie‐related herbs, in this study, seven sorts of representative Bixie herbs (Dioscorea collettii, D. zingiberensis, D. nipponica, D. septemloba, Smilax china, S. glabra, and Heterosmilax japonica) were characterized based on the microscopic examination of their powders and cryotomed transverse sections. This is not only the first attempt to distinguish Bixie herbs by a comprehensive microscopic techniques, including common light microscopy, fluorescence microscopy, and polarized light microscopy, but also it is the first research to observe characteristics of transections of crude drugs under polarized lighting for the purpose of authentication. Polarized light has been found to provide a number of unique characteristics. The results indicate that starch granules, stone cells, vascular bundles, and other significant tissue features can be used to authenticate “Bixie” herbs. The method was proven to be quick, handy, specific, and simple. It should be widely applicable to other herbal materials. Microsc. Res. Tech. 77:57–70, 2014. © 2013 Wiley Periodicals, Inc.     

Comparative authentication of three “snow lotus” herbs by macroscopic and microscopic features

“Snow lotus” is a famous Chinese Materia Medica derived from species of the genus Saussurea (Compositae). To differentiate three representative easily‐confused snow lotus herbs, namely, Saussurea involucrata (Kar. et Kir.) Sch.‐Bip, Saussurea laniceps Hand.‐Mazz., and Saussurea medusa Maxim., macroscopic features of the three herbs were systemically observed, and microscopic features were compared by using ordinary light microscopy, polarized light microscopy and scanning electron microscopy (SEM). The results indicate that, as for macroscopic identification, capitula situation and arrangement, and as for microscopic identification, pollen grains, nonglandular hairs, glandular hairs, and cells of inner surface of the microdiodange can be used to authenticate the three snow lotus herbs. Comprehensive table comparing the characteristics were presented in this study. SEM has been found to provide a number of unique characteristics of pollen grains. Based on the observation of pollen grains, evolution sequence of the three species was speculated. The present method was proven to be efficient, convenient, simple, and reliable, which was successfully applied to the authentication of three snow lotus herbs. Microsc. Res. Tech.1 77:631–641, 2014. © 2014 Wiley Periodicals, Inc.     

Application of microscopy for discrimination of eight Swertia species utilized in the traditional Chinese medicine “Qingyedan”

Many Swertia species are utilized as a traditional medicine under the name “Qingyedan” in China, but are easily confused with one another. To distinguish eight Swertia species (S. mileensis, S. cincta, S. patens, S. punicea, S. delavayi, S. nervosa, S. macrosperma, and S. yunnanensis) and to ensure their safety and efficacy, the microscopic and macroscopic characteristics of the roots, stems, leaves, and flowers of them were examined. The results showed that microscopic and macroscopic features helpful for authentication of the eight species were the sinuosity of the anticlinal walls of epidermal cells and presence or absence of hairs on the leaf lamina; presence or absence of V‐shaped fibers and fibers with sinuous abaxial wall in the sepals; shape of epidermal cells and pattern of papillae on hairs on the margin of corolla nectary; distribution of stomata in leaf and sepal epidermises, stone cells in cortex and phloem of roots and in cortex and pith of stems, crystals in parenchymatous cells of mesophyll and stem, stomata size, stem diameter, and 4‐ or 5‐merous flowers, and so on. Two keys to the eight Swertia species based on macroscopic and microscopic characteristics are presented. The study indicates that microscopy and related techniques are convenient, practicable, and can be unambiguously applied for authentication of Swertia species. Microsc. Res. Tech. 76:296–310, 2013. © 2013 Wiley Periodicals, Inc.     

Silver impregnation applied to striated muscle: The sarcoplasmic reticulum

The classical black reaction developed by Camillo Golgi is shown to impregnate the tubules and fenestrations of the sarcoplasmic reticulum (SR) in striated muscle. This is a double impregnation of chromate and silver, which usually fills extracellular spaces. The method is difficult insofar as long incubation times are required, and location of the successfully “stained” SR in plastic-embedded tissue blocks is unpredictable. The light microscope is absolutely necessary to find the good regions which can then be cut from the blocks in 1-μm-thick sections and examined in the electron microscope. Stereo pairs give the best results since these resolve overlap problems common to thick sections. A variety of artifacts are illustrated which can help avoid erroneous interpretations. The Golgi-“stained” SR shows this elusive network with unsurpassed contrast and should benefit the morphological studies of muscle-membrane enthusiasts.     

Do SEII Electrons Really Degrade SEM Image Quality?

Generally, in scanning electron microscopy (SEM) imaging, it is desirable that a high‐resolution image be composed mainly of those secondary electrons (SEs) generated by the primary electron beam, denoted SE_I. However, in conventional SEM imaging, other, often unwanted, signal components consisting of backscattered electrons (BSEs), and their associated SEs, denoted SE_II, are present; these signal components contribute a random background signal that degrades contrast, and therefore signal‐to‐noise ratio and resolution. Ideally, the highest resolution SEM image would consist only of the SE_I component. In SEMs that use conventional pinhole lenses and their associated Everhart–Thornley detectors, the image is composed of several components, including SE_I, SE_II, and some BSE, depending on the geometry of the detector. Modern snorkel lens systems eliminate the BSEs, but not the SE_IIs. We present a microfabricated diaphragm for minimizing the unwanted SE_II signal components. We present evidence of improved imaging using a microlithographically generated pattern of Au, about 500 nm thick, that blocks most of the undesired signal components, leaving an image composed mostly of SE_Is. We refer to this structure as a “spatial backscatter diaphragm.” SCANNING 35:1‐6, 2013. © 2012 Wiley Periodicals, Inc.     

Making the practically impossible “Merely difficult”—Cryogenic FIB lift‐out for “Damage free” soft matter imaging

The preparation of thinned lamellae from bulk samples for transmission electron microscopy (TEM) analysis has been possible in the focussed ion beam scanning electron microscope (FIB‐SEM) for over 20 years via the in situ lift‐out method. Lift‐out offers a fast and site specific preparation method for TEM analysis, typically in the field of materials science. More recently it has been applied to a low‐water content biological sample (Rubino 2012). This work presents the successful lift‐out of high‐water content lamellae, under cryogenic conditions (cryo‐FIB lift‐out) and using a nanomanipulator retaining its full range of motion, which are advances on the work previously done by Rubino (2012). Strategies are explored for maintaining cryogenic conditions, grid attachment using cryo‐condensation of water and protection of the lamella when transferring to the TEM. Microsc. Res. Tech. 79:298–303, 2016. © 2016 Wiley Periodicals, Inc.     

Surface roughness and filler particles characterization of resin‐based composites

The purpose of this study was to evaluate the surface roughness (Ra), and the morphology and composition of filler particles of different composites submitted to toothbrushing and water storage. Disc‐shaped specimens (15 mm × 2 mm) were made from five composites: two conventional (Z100?, and Filtek? Supreme Ultra Universal, 3M), one “quick‐cure” (Estelite ∑ Quick, Tokuyama), one fluoride‐releasing (Beautiful II, Shofu), and one self‐adhering (Vertise Flow, Kerr) composite. Samples were finished/polished using aluminum oxide discs (Sof‐Lex, 3M), and their surfaces were analyzed by profilometry (n = 5) and scanning electron microscopy (SEM; n = 3) at 1 week and after 30,000 toothbrushing cycles and 6‐month water storage. Ra data were analyzed by two‐way analysis of variance and Tukey's test (α = 0.05). Filler particles morphology and composition were analyzed by SEM and X‐ray dispersive energy spectroscopy, respectively. Finishing/polishing resulted in similar Ra for all the composites, while toothbrushing and water storage increased the Ra of all the tested materials, also changing their surface morphology. Beautifil II and Vertise Flow presented the highest Ra after toothbrushing and water storage. Filler particles were mainly composed of silicon, zirconium, aluminum, barium, and ytterbium. Size and morphology of fillers, and composition of the tested composites influenced their Ra when samples were submitted to toothbrushing and water storage.     

The innovative safe fixative for histology,histopathology, and immunohistochemistry techniques: “Pilot study using shellac alcoholic solution fixative”

The concerns over health and workplace hazards of formalin fixative, joined to its cross‐linking of molecular groups that results in suboptimal immunohistochemistry, led us to search for an innovative safe fixative. Shellac is a natural material which is used as a preservative in foods and pharmaceutical industries. This study was undertaken to evaluate the fixation adequacy and staining quality of histopathological specimens fixed in the “shellac alcoholic solution” (SAS), and also to determine the validity of immunohistochemical staining of SAS‐fixed material in comparison to those fixed in formalin. Fresh samples from 26 cases from various human tissues were collected at the frozen section room of King Abdulaziz University Hospital, and fixed in SAS fixative or in neutral buffered formaldehyde (NBF) for 12, 18, 24, and 48 h, and processed for paraffin sectioning. Deparaffinized sections were stained with hematoxylin and eosin (H&E) and immunostained for different antigens. The tissues fixed in SAS for >18 h showed best staining quality of H&E comparable to NBF‐fixed tissues. Comparison of the immunohistochemical staining of different tissues yielded nearly equivalent readings with good positive nuclear staining quality in both fixatives. These findings support the fixation and preservation adequacy of SAS. Furthermore, it was concluded that the good staining quality obtained with SAS‐fixed tissues, which was more or less comparable with the quality obtained with the formalin fixed tissues, supports the validity of this new solution as a good innovative fixative. Microsc. Res. Tech. 77:385–393, 2014. © 2014 Wiley Periodicals, Inc.     

Color cathodoluminescence-scanning electron microscopy study of the 4H-SiC heteroepitaxial layers grown by sublimation “sandwich method”

The color cathodoluminescence scanning electron microscopy (CCL-SEM) technique was used for the study of the 4H-SiC epitaxial layers grown by sublimation “sandwich method” on the 6H- or 21R substrates. Elements of the BIY group were introduced for polytype transformations. The method makes it possible to control the polytype in thin layers (0.1–2 μam). The effect of supersaturation and the growth rate on 4H polytype formation have been studied. It was shown that the probability of polytype transformation depends on the configuration of the substrate surface. At low supersaturation, 4H polytype nuclei arise predominantly on projected areas of the (0001)C substrate surface, which had no growth centers such as screw dislocations.     

Ultrastructural and three‐dimensional study of post‐LASIK ectasia cornea

INTRODUCTION: Post‐laser in situ keratomileusis (LASIK) corneal ectasia is a serious late postoperative complication. Here, we report the ultrastructural features of the post‐LASIK cornea of two patients. METHODS: Two normal corneas (age 24 and 37 years old) and two post‐LASIK ectaic corneas from two patients (A and B) were studied. The “patient A” (age 27 years) underwent penetrating keratoplasty and “patient B” (age 31 years) underwent deep‐anterior lamellar keratoplasty. The excised corneas were processed for light and electron microscopy. A total of 120 images for three‐dimensional (3D) reconstruction were taken by using the software “Recorder” and using a bottom mounted camera “Quemesa” attached to a JOEL 1400 transmission electron microscope. The 3D images were constructed using “Visual Kai” software. RESULTS: In the post‐LASIK cornea, the hemidesmosomes, the basement membrane, and Bowman”s layer were abnormal. The stromal lamellae were thin and disorganized. The collagen fibrils (CFs) diameter and interfibrillar spacing had decreased. Aggregated microfibrils were present in the Bowman's layer and all parts of the stroma. A large number of microfilaments were present at the detachment end of the flap and residual stroma. The 3D images showed the presence of collagen microfibrils and proteoglycans (PGs) within the CF of the normal and post‐LASIK cornea. The collagen microfibrils and PGs within the CFs had degenerated in the post‐LASIK cornea. CONCLUSION: Collagen microfibrils and PGs within the CFs were degenerated, leading to the degeneration of CFs, followed by the disorganization of lamellae in post‐LASIK cornea. The CFs diameter and interfibrillar spacing decreased. Microsc. Res. Tech. 77:91–98, 2014. © 2013 Wiley Periodicals, Inc.     

Developing of N‐(4‐methylpyrimidine‐2‐yl)methacrylamide Langmuir–Blodgett thin film chemical sensor via quartz crystal microbalance technique

In the present work, the characterization and gas sensing properties of newly synthesized N‐(4‐methylpyrimidine‐2‐yl)methacrylamide ( N‐MPMA ) monomer Langmuir–Blodgett (LB) thin films were investigated. The UV–visible spectroscopy, quartz crystal microbalance (QCM), and atomic force microscopy were utilized to characterize N‐MPMA LB thin films. The surface behavior of N‐MPMA monolayer was stable and allowed an effective transfer at a surface pressure of 14 mN/m. The mass change/unit area value of the N‐MPMA LB thin film deposited quartz crystal surfaces was investigated. The amount of N‐MPMA LB thin film deposited on the substrate for bilayer was calculated as 228.72 ng (86.31 ng/mm²) and 12.5 Hz frequency shift was observed for each layer of the N‐MPMA film. The kinetic responses of N‐MPMA LB film against chloroform, dichloromethane, benzene, and toluene were measured via QCM system at room temperature. N‐MPMA QCM sensor results displayed that chloroform has the largest frequency shifts compared with the other vapors used in the present work and these results can be illuminating in terms of physical properties of organic vapors.     

A microstructural study of gallbladder stones using scanning electron microscopy

Objective: The objective of this study was to describe the microstructure of different types of gallbladder stones to better understand the basis of gallbladder stone formation. Methods: Gallbladder stones from 387 patients with cholecystolithiasis were first analyzed by Fourier transform Infrared spectroscopy to identify the type of the gallbladder stone, and they were then examined using scanning electron microscopy to define their microstructure. Results: Cholesterol stones were mainly composed of plate‐like or lamellar cholesterol crystals stacked tightly in a radial, cord‐like, or irregular staggered arrangement. A small number of bilirubinate particles were seen occasionally. Pigment stones were mainly composed of loosely arranged bilirubinate particles with different shapes (sphere‐like, clumping‐like, or amorphous). Calcium carbonate stones were composed of calcium carbonate crystals having many shapes (bulbiform, ellipsoid, fagot‐shaped, fusiform, hawthorn‐shaped, cuboid, button‐shaped, lamellar, broken firewood‐shaped, rod‐shaped, acicular, or crushed sugar cane‐shaped). Bulbiform shaped crystals were the most common. Phosphate stones were mainly composed of different sized echin‐sphere‐like or rough bulbiform crystals. Bilirubinate particles were always adherent. Calcium stearate stones usually had a network structure with adherent bilirubinate particles. Protein stones usually had a honeycomb or chrysanthemum petal‐like structure. Cystine stones were composed of hexagonal cystine crystals, some of which had prominent edges. Mixed stones presented different shapes according to their mixed components. Conclusion: Different types of gallbladder stones had characteristic shapes and elements. This study provides an objective basis for further research regarding gallbladder stone formation. Microsc. Res. Tech. 76:443–452, 2013. © 2013 Wiley Periodicals, Inc.     

Study on water‐dispersible colloids in saline–alkali soils by atomic force microscopy and spectrometric methods

Recent studies have revealed that water‐dispersible colloids play an important role in the transport of nutrients and contaminants in soils. In this study, water‐dispersible colloids extracted from saline–alkali soils have been characterized by atomic force microscopy (AFM), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and UV absorption spectra. AFM observation indicated that the water‐dispersible colloids contain some large plates and many small spherical particles. XRD, XPS, and UV absorption measurement revealed that the water‐dispersible colloids are composed of kaolinite, illite, calcite, quartz and humic acid. In addition, UV absorption measurement demonstrated that the humic acids are associated with clay minerals. Water‐dispersible colloids in the saline–alkali soils after hydrolyzed polymaleic anhydride treatment and an agricultural soil (nonsaline–alkali soil) were also investigated for comparison. The obtained results implied that the saline–alkali condition facilitates the formation of a large quantity of colloids. The use of AFM combined with spectrometric methods in the present study provides new knowledge on the colloid characteristics of saline–alkali soils. Microsc. Res. Tech. 79:525–531, 2016. © 2016 Wiley Periodicals, Inc.     

Immobilization and stretching of 5′‐pyrene‐terminated DNA on carbon film deposited on electron microscope grid

The immobilization and stretching of randomly coiled DNA molecules on hydrophobic carbon film is a challenging microscopic technique, which possess various applications, especially for genome sequencing. In this report the pyrenyl nucleus is used as an anchor moiety to acquire higher affinity of double stranded DNA to the graphite surface. DNA and pyrene are joined through a linker composed of four aliphatic methylene groups. For the preparation of pyrene‐terminated DNA a multifunctional phosphoramidite monomer compound was designed. It contains pyrenylbutoxy group as an anchor moiety for π‐stacking attachment to the carbon film, 2‐cyanoethyloxy, and diisopropylamino as coupling groups for conjugation to activated oligonucleotide chain or DNA molecule. This monomer derivative was suitable for incorporation into automated solid‐phase DNA synthesis and was attached to the 5′ terminus of the DNA chain through a phosphodiester linkage. The successful immobilization and stretching of pyrene‐terminated DNA was demonstrated by conventional 100 kV transmission electron microscope. The microscopic analysis confirmed the stretched shape of the negatively charged nucleic acid pieces on the hydrophobic carbon film. Microsc. Res. Tech. 78:994–1000, 2015. © 2015 Wiley Periodicals, Inc.     

Increased androgen receptor and remodeling in the prostatic stroma after the inhibition of 5‐alpha reductase and aromatase in gerbil ventral prostate

Prostate require high levels of steroidogenic enzymes such as 5α‐reductase (5α‐r) and Aromatase (Aro) for the formation of active steroids. Dihydrotestosterone (DHT), the prostate dominant androgen, is converted from testosterone (T) by the action of 5α‐r. Aro provides an alternative pathway for estrogen, via T aromatization. Since prostatic maintenance is dependent on both reciprocal stromal–epithelial interaction and regulation by steroids, this study aimed to elucidate what the absence of 5α‐r and Aro enzymes provokes in the prostate microenvironment after their long‐term inhibition. Data obtained 1 day after the 30 consecutive days of enzymatic inhibition with Finasteride (5α‐r inhibitor) and Letrozole (Aro inhibitor) demonstrated a marked stromal remodeling, with an increased deposition of extracellular matrix (ECM) proteins besides androgen receptor (AR) overexpression in the three phases of postnatal development analyzed. The subepithelial area of acini from ventral prostate presented collagen and reticular fibers accumulation, besides various altered and active fibroblasts. The AR content immunostaining was elevated after enzymatic inhibition therapy, mainly in the nuclei of epithelial cells. Similar data were observed in the ventral prostates even 21 days after the end of treatments. Results obtained following the long‐term inhibition of 5α‐r and Aro are relevant and highlight the actions of these enzymes as crucial not only for the maintenance of tissue architecture and ECM arrangement but also for androgen and AR function. The long‐term absence of their action imposes a novel situation on the prostate from which its normal physiology could not be restored by the conclusion of the treatments. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.