A semiautomatic method for in vivo three-dimensional quantitative analysis of fascial layers mobility based on 3D ultrasound scans.

PURPOSE: Recently, there has been an increasing interest in the role of deep fascia mobility in musculoskeletal dynamics and chronic pain mechanisms; however, no strategies have been presented so far to study in vivo fascial motion in 3D. This paper presents a semiautomatic method, based on ultrasound (US) imaging, enabling a 3D evaluation of fascia mobility. METHODS: The proposed approach relies on the acquisition of 3D US datasets at rest and during a voluntary muscular contraction and consists of two phases: 3D US dataset analysis and generation of a displacement vector field using a block matching technique (Phase 1) and validation and filtering of the resulting displacement vector field for outliers removal (Phase 2). The accuracy and effectiveness of the proposed method were preliminarily tested on different 3D US datasets, undergoing either simulated (procedural) or real (muscular contraction) deformations. RESULTS: As for the simulated deformation, estimated displacement vectors resulting from Phase 1 presented a mean magnitude percentage error of 8.05 % and a mean angular error of 4.78° which, after Phase 2, were reduced by 69.44 and by 83.05 %, respectively. Tests on real deformations further validated the effectiveness of Phase 2 in the removal of outliers from the displacement vector field. CONCLUSIONS: Obtained results preliminarily demonstrate the viability of the proposed algorithm for the analysis of fascia mobility. Such analysis can enable clinicians to better understand the fascia role in musculoskeletal dynamics and disorder. Further experiments are needed to optimize the method in consideration of the anatomical region to be studied.

A 3D sparse motion field filtering for quantitative analysis of fascial layers mobility based on 3D ultrasound scans.

In the last few years, there has been an increasing interest in the role of deep fascia mobility in musculoskeletal dynamics and chronic pain mechanisms. In a previous paper we presented an innovative semiautomatic approach to evaluate the 3D motion of the fascia using ultrasound (US) imaging, generating a sparse deformation vector field. This paper presents an improvement of our original method, focusing on the filtering of the sparse vector field and its validation. Moreover, in order to evaluate the performance of the algorithm, a method is proposed to generate synthetic deformation vector fields, including: expansion, rotation, horizontal shear, and oblique shear components. Preliminary tests on the final synthetic deformation vector fields showed promising results. Further experiments are required in order to optimize the tuning of the algorithm.

Comparative ultrasonographic evaluation of the Achilles paratenon in symptomatic and asymptomatic subjects: an imaging study.

Achilles tendon analysis represents one of the most frequently requested ultrasonographic evaluations, due to the high incidence of tendinopathy. Various authors have described inflammatory features of the paratenon recruited 22 subjects complaining of pain in the mid-portion of the Achilles tendon and 22 healthy subjects. Both groups underwent ultrasonographic examination and Victorian Institute of Sport Assessment-Achilles questionnaire administration. It was found statistically significant inter-group differences of the paratenon (p = 0.0001) as well as tendon thickness (p < 0.0001). Our results show that Achilles symptoms could also be associated with an increase in the paratenon thickness. We suggest that clinicians should carefully analyze paratenon thickness when evaluating patients with Achillodynia using ultrasound. It may be that the paratenon, when thickened, may explain some of the painful symptoms reported by patients and it is associated with a tendinopathy process, hence we suggest careful analysis in patients with Achillodynia.

Natale et. al.'s response to Stecco's fascial nomenclature editorial.

Despite their importance in anatomy, physiology, pathology and surgery, the fasciae and the fascial spaces have been poorly described in classic textbooks. This little attention depends on the fact that these fasciae vary in thickness and composition, especially at the cervical level. Indeed, in the main literature they have been described in different forms. Furthermore, the definition itself of the fascia is not consistent in a variety of authors. As a consequence, different criteria have been used to define and classify the fascial systems. In this paper, a brief terminological history and the most common nomenclatures and classifications of the fascia have been summarized.

Cryopreservation effects on Wharton's Jelly Stem Cells proteome.

Cryopreservation is the only method for long-term storage of viable cells and tissues used for cellular therapy, stem cell transplantation and/or tissue engineering. However, the freeze-thaw process strongly contributes to cell and tissue damage through several mechanisms, including oxidative stress, cell injury from intracellular ice formation and altered physical cellular properties. Our previous proteomics investigation was carried out on Wharton's Jelly Stem Cells (WJSCs) having similar properties to adult mesenchymal stem cells and thus representing a rich source of primitive cells to be potentially used in regenerative medicine. The aim of the present work was to investigate molecular changes that occur in WJSCs proteome in different experimental conditions: fresh primary cell culture and frozen cell. To analyze changes in protein expression of WJSCs undergoing different culturing procedures, we performed a comparative proteomic analysis (2DE followed by MALDI-TOF MS/MS nanoESI-Q-TOF MS coupled with nanoLC) between WJSCs from fresh and frozen cell culturing, respectively. Frozen WJSCs showed qualitative and quantitative changes compared to cells from fresh preparation, expressing proteins involved in replication, cellular defence mechanism and metabolism, that could ensure freeze-thaw survival. The results of this study could play a key role in elucidating possible mechanisms related to maintaining active proliferation and maximal cellular plasticity and thus making the use of WJSCs in cell therapy safe following bio-banking.

Simultaneous tracking of catheters and guidewires: comparison to standard fluoroscopic guidance for arterial cannulation.

OBJECTIVES: The purpose of this in vitro study was to clinically assess the feasibility of a three-dimensional (3D) electromagnetic (EM) navigator, including sensorized catheters and guidewires, to determine any reduction in radiation dose and contrast medium injection. METHODS: The study was performed using a navigator prototype developed at the EndoCAS center. The system includes catheters and guidewires simultaneously tracked with an EM localizer (Aurora, Northern Digital, Waterloo, Canada). Tests were performed on a commercial abdominal aortic aneurysm model. Fifteen operators were asked to cannulate renal arteries using the conventional fluoroscopic guidance and the EM navigator without fluoroscopic support. Each trial was video-recorded and analyzed for timing and success of completing the cannulation task by two blinded and independent observers. Performances were also qualitatively evaluated using the Imperial College Endovascular Cannulation Scoring Tool (IC3ST). Moreover, a questionnaire was administered to participants to evaluate the navigator potentialities. RESULTS: Quantitative analysis results show no significant difference between the fluoroscopic and EM guidance regarding the total procedure time (median 2.36 minutes [interquartile range {IQR} = 1.26-4.7) vs. 2.95 min [IQR = 1.35-5.38], respectively; p = .93); number of total hits with catheter/guidewire tip to vessels wall (median 5.50 [IQR = 2.00-10.00] vs. 3.50 [IQR = 2.50-7.00], respectively; p = .65); and number of attempts at cannulation (median 4.0 [IQR = 2.00-5.00] vs. 4.0 [IQR = 2.00-5.00], respectively; p = .72]. Moreover, there was no significant difference between the IC3ST score obtained using the EM navigator and the traditional method (average 22.37 [STD = 7.95] vs. 21.58 [STD = 6.86]; p = .92). Finally, questionnaire results indicate a general agreement concerning the navigator usefulness, which clearly shows the positions of instruments inside the 3D model of the patient's anatomy. Participants also agreed that the navigator can reduce the amount of contrast media delivered to the patient, as well as fluoroscopy time. CONCLUSIONS: This work provides proof of concept that simultaneous EM navigation of guidewires and catheters is feasible without the use of live fluoroscopic images.

In vitro reparative dentin: a biochemical and morphological study.

In this study, starting from human dental pulp cells cultured in vitro, we simulated reparative dentinogenesis using a medium supplemented with different odontogenic inductors. The differentiation of dental pulp cells in odontoblast-like cells was evaluated by means of staining, and ultramorphological, biochemical and biomolecular methods. Alizarin red staining showed mineral deposition while transmission electron microscopy revealed a synthesis of extracellular matrix fibers during the differentiation process. Biochemical assays demonstrated that the differentiated phenotype expressed odontoblast markers, such as Dentin Matrix Protein 1 (DMP1) and Dentin Sialoprotein (DSP), as well as type I collagen. Quantitative data regarding the mRNA expression of DMP1, DSP and type I collagen were obtained by Real Time PCR. Immunofluorescence data demonstrated the various localizations of DSP and DMP1 during odontoblast differentiation. Based on our results, we obtained odontoblast-like cells which simulated the reparative dentin processes in order to better investigate the mechanism of odontoblast differentiation, and dentin extracellular matrix deposition and mineralization.

High-intensity exercise training induces morphological and biochemical changes in skeletal muscles.

IN THE PRESENT STUDY WE INVESTIGATED THE EFFECT OF TWO DIFFERENT EXERCISE PROTOCOLS ON FIBRE COMPOSITION AND METABOLISM OF TWO SPECIFIC MUSCLES OF MICE: the quadriceps and the gastrocnemius. Mice were run daily on a motorized treadmill, at a velocity corresponding to 60% or 90% of the maximal running velocity. Blood lactate and body weight were measured during exercise training. We found that at the end of training the body weight significantly increased in high-intensity exercise mice compared to the control group (P=0.0268), whereas it decreased in low-intensity exercise mice compared to controls (P=0.30). In contrast, the food intake was greater in both trained mice compared to controls (P < 0.0001 and P < 0.0001 for low-intensity and high-intensity exercise mice, respectively). These effects were accompanied by a progressive reduction in blood lactate levels at the end of training in both the exercised mice compared with controls (P=0.03 and P < 0.0001 for low-intensity and high-intensity exercise mice, respectively); in particular, blood lactate levels after high-intensity exercise were significantly lower than those measured in low-intensity exercise mice (P=0.0044). Immunoblotting analysis demonstrated that high-intensity exercise training produced a significant increase in the expression of mitochondrial enzymes contained within gastrocnemius and quadriceps muscles. These changes were associated with an increase in the amount of slow fibres in both these muscles of high-intensity exercise mice, as revealed by the counts of slow fibres stained with specific antibodies (P < 0.0001 for the gastrocnemius; P=0.0002 for the quadriceps). Our results demonstrate that high-intensity exercise, in addition to metabolic changes consisting of a decrease in blood lactate and body weight, induces an increase in the mitochondrial enzymes and slow fibres in different skeletal muscles of mice, which indicates an exercise-induced increase in the aerobic metabolism.

High-intensity exercise training produces morphological and biochemical changes in adrenal gland of mice.

The effects of training are dependent on complex, adaptive changes which are induced by acute physical exercise at different levels. In particular, evidence shows that the hypothalamus-pituitary-adrenocortical axis, as well as the sympatho-adrenomedullary system, is mainly involved in mediating the physiological effects of physical exercise. The aim of the present study was to investigate, through a morphological and biochemical approach, the effects of training on the adrenal gland of mice, following two different protocols consisting of either low- or high-intensity training. Mice were run daily on a motorised treadmill for 8 weeks, at a velocity corresponding to 60% (low-intensity exercise) or 90% (high-intensity exercise) of the maximal running velocity previously determined by an incremental exercise test. We found that physical exercise produced an increase in the adrenal gland size compared with the control (sedentary) mice. The increase was 31.04% for mice that underwent high-intensity exercise and 10.08% for mice that underwent low intensity exercise, and this appeared to be the result of an increase in the area of both the adrenal cortex and adrenal medulla. Morphological analysis of the adrenal cortex showed that both types of exercise produced an increase in cytoplasmic vacuoles in steroidogenic cells, appearing more abundant after high-intensity exercise. No change was found in the reticulate zone. In the adrenal medulla, despite the absence of morphological changes, immunohistochemistry for tyrosine hydroxylase, dopamine ß-hydroxylase and phenyl-ethanolamine-N-methyltransferase demonstrated an increased immunopositivity for these cathecolamine-synthesizing enzymes after intense exercise. These results were confirmed by immunoblot accompanied by densitometric analysis.

A hypothesis on prion disorders: are infectious, inherited, and sporadic causes so distinct?

Prion diseases include a group of either sporadic, inherited or infectious disorders characterized by spongiform neurodegeneration and reactive glyosis in several brain regions. Whatever the origin, the neuropathological hallmark of prion diseases is the presence of brain aggregates containing an altered isoform of a cellular protein, named prion protein. Recent findings show the potential toxicity of the normal cellular prion protein, which occurs when its physiological metabolism is altered. In particular, several studies demonstrate that accumulation of the prion protein in the cytosol can be a consequence of an increased amount of misfolded prion proteins, a derangement of the correct protein trafficking or a reduced activity of the ubiquitin-proteasome system. The same effects can be a consequence of a mutation in the gene coding for the prion protein. In all these conditions, one assists to accumulation and self-replication of insoluble prion proteins which leads to a severe disease resembling what observed following typical "prion infections". This article provides an opinion aimed at reconciling the classic Prusiner's theory concerning the "prion concepts" with the present knowledge arising from experimental studies on neurodegenerative disorders, suggesting a few overlapping steps in the pathogenesis of these diseases.

Similarities between methamphetamine toxicity and proteasome inhibition.

The monoamine neurotoxin methamphetamine (METH) is commonly used as an experimental model for Parkinson's disease (PD). In fact, METH-induced striatal dopamine (DA) loss is accompanied by damage to striatal nerve endings arising from the substantia nigra. On the other hand, PD is characterized by neuronal inclusions within nigral DA neurons. These inclusions contain alpha-synuclein, ubiquitin, and various components of a metabolic pathway named the ubiquitin-proteasome (UP) system, while mutation of genes coding for various components of the UP system is responsible for inherited forms of PD. In this presentation we demonstrate for the first time the occurrence of neuronal inclusions in vivo in the nigrostriatal system of the mouse following administration of METH. We analyzed, in vivo and in vitro, the shape and the fine structure of these neuronal bodies by using transmission electron microscopy. Immunocytochemical investigation showed that these METH-induced cytosolic inclusions stain for ubiquitin, alpha-synuclein, and UP-related molecules, thus sharing similar components with Lewy bodies occurring in PD, with an emphasis on enzymes belonging to the UP system. In line with this, blockade of this multicatalytic pathway by the selective inhibitor epoxomycin produced cell inclusions with similar features. Moreover, using a multifaceted pharmacological approach, we could demonstrate the need for endogenous DA in order to form neuronal inclusions.

Effects of repeated low doses of MDMA on EEG activity and fluoro-jade B histochemistry.

The psychostimulant 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") is an amphetamine derivative that is widely abused. In previous studies, depending on the animal species, neurotoxicity has been demonstrated for either serotonin (5-HT) or/and dopamine (DA) nerve endings. These studies focused on the basal ganglia circuitry; however, in humans chronic abuse of MDMA often results in neurological symptoms that last after MDMA withdrawal and are not related to the extrapyramidal system such as electroencephalographic (EEG) abnormalities and cognitive impairment. These alterations might be due to the concomitant intake of other illicit compounds, the consequence of MDMA-induced hyperthermia, or to a primary neurotoxicity directed to extrastriatal regions. These observations call for a more in-depth analysis on the potential involvement of brain areas outside the basal ganglia in the toxic effects induced primarily by MDMA. In the present study, we treated C57Black mice chronically (25 days) with daily injections of MDMA (2.5 mg/kg). During treatments, mice were monitored in order to detect behavioral modifications, and epidural electrodes were installed to perform EEG recording. Behavioral data showed a sensitization as measured by locomotor activity, which related to progressive and long-lasting EEG changes and neuronal degeneration within the hippocampus.

Distribution of 3-nitrotyrosine in the nasal polyps of atopic patients.

OBJECTIVE: To investigate whether formation of nitrotyrosine in the nasal polyps of atopic patients occurs. STUDY DESIGN: A nonrandomized, retrospective, controlled qualitative and quantitative study. METHODS: Nasal polyp tissue samples were acquired from 12 atopic patients. Control fragments of nasal mucosa were taken from 10 patients undergoing corrective surgery of the nasal septum. For routine histologic examinations, hematoxylin-eosin staining was used. Low-magnification microscopy was designed to yield pathologic characteristics and high magnification to quantify the number of eosinophils in the subepithelial connective tissue. Presence of nitrotyrosine was assessed by immunohistochemical method. RESULTS: Hematoxylin-eosin staining revealed presence of numerous eosinophils in the epithelium and in the subepithelial connective tissue. All polyps were characterized by epithelial damage. Nitrotyrosine was present in the eosinophils, in the ciliated cell, and in cells of the damaged epithelium. Goblet cells, glands, and vessels were found to be negative. No significant differences concerning the localization of nitrotyrosine were recognized among the examined nasal polyps. CONCLUSIONS: Nitrotyrosine immunohistochemical staining in nasal-polyp tissues suggested the existence of progressive epithelium injury caused by peroxynitrite. Consequences of peroxynitrite formation in eosinophils remain to be precisely established. The lack of nitrotyrosine in glands and blood vessels indicated that peroxynitrite does not have a significant role in the vascular and glandular dysfunction of nasal polyps.

DNA damage and ubiquitinated neuronal inclusions in the substantia nigra and striatum of mice following MDMA (ecstasy).

RATIONALE: 3,4-Methylenedioxymethamphetamine (MDMA) is an amphetamine derivative, which is neurotoxic to both serotonin (5HT) and dopamine (DA) nerve terminals. Previous reports, carried out in rodents and non-human primates, demonstrated neurotoxicity to monoamine axon terminals, although no study has analyzed nigral and striatal cell bodies at the sub-cellular level. OBJECTIVE: In this study, we examined intrinsic nigral and striatal cells, and PC12 cell cultures to evaluate whether, in mice, MDMA might affect nigral and striatal cell bodies. METHODS: After administering MDMA, we analyzed effects induced in vivo and in vitro using high-performance liquid chromatography (HPLC) analysis, light- and electron microscopy with immunocytochemistry, and DNA comet assay. RESULTS: We found that MDMA (5 mg/kg x4, 2 h apart), besides a decrease of nigrostriatal DA innervation and 5HT loss, produces neuronal inclusions within nigral and intrinsic striatal neurons consisting of multi-layer ubiquitin-positive whorls extending to the nucleus of the cell. These fine morphological changes are associated with clustering of heat shock protein (HSP)-70 in the nucleus, very close to chromatin filaments. In the same experimental conditions, we could detect oxidation of DNA bases followed by DNA damage. The nature of inclusions was further investigated using PC12 cell cultures. CONCLUSIONS: The present findings lead to re-consideration of the neurotoxic consequences of MDMA administration. In fact, occurrence of ubiquitin-positive neuronal inclusions and DNA damage both in nigral and striatal cells sheds new light into the fine alterations induced by MDMA, also suggesting the involvement of nuclear and cytoplasmic components of the ubiquitin-proteasome pathway in MDMA toxicity.

Clinical improvement in systemic sclerosis resulting from urokinase therapy explained by light and electron microscopy skin examination.

OBJECTIVE: In our previous work, patients affected by SSc were treated with intravenous urokinase and showed clinical improvement. In this study we used microscopy to document ultrastructural alterations occurring in sclerodermic skin from SSc patients treated with urokinase. METHODS: Ten patients with SSc were selected for this study. Skin biopsies were taken from the medial side of the right forearm on the third proximal on the volar surface. The patients were then treated with urokinase for 7 consecutive days. At the end of the treatment, the patients were examined and a new skin biopsy was taken close to the above-mentioned zone of the forearm for optic and electron microscopy examination. RESULTS: The patients showed a gradual improvement of the skin after urokinase treatment. Raynaud's appeared to be less intense, and they had an increased articular range, with the restoration of movements that had previously been limited. Histological findings showed that, after treatment, skin alterations appeared attenuated, in particular the connective tissue showed a decreased density and inflammatory infiltrate was slight. Electron microscopy findings showed that collagen fibres appeared to have a more regular diameter, and the capillary vessels' lining was thicker, with fewer pinocytotic vesicles. CONCLUSION: These observations show that urokinase treatment seems to be an interesting therapeutic strategy to consider for the treatment of SSc.

Amphetamines induce ubiquitin-positive inclusions within striatal cells.

The present study explores whether effects induced by amphetamine derivatives on striatal GABA cells might be connected with effects on dopamine (DA) metabolism. Methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") were administered to C57Black mice following a dosage regimen in which various doses of both drugs were injected i.p. at 2-h intervals. Neuronal inclusions produced under these experimental conditions were examined under electron microscopy. Drugs reducing DA availability prevented inclusion formation; conversely we observed that increasing DA synthesis or impairing physiological DA degradation enhanced the number of inclusions. The present study indicates that the presence of extracellular striatal DA is essential for the production of subcellular alterations induced by amphetamine derivatives. This is in line with a recent hypothesis connecting striatal DA release with degeneration of striatal GABA neurons.

Recent knowledge on molecular components of Lewy bodies discloses future therapeutic strategies in Parkinson's disease.

Lewy bodies (LB) were first described by Lewy in 1912 [1] as neuronal pale eosinophilic inclusions which became a pathological hallmark of Parkinson s disease (PD). In his original study, Lewy defined these inclusions as pale eosinophilic cytoplasmic structures, and studies since then have revealed LB to be ubiquitin-, alpha-synuclein-, and parkin-containing inclusions. This suggests that knowledge of the biochemical steps involved in the genesis of LB might disclose a final common pathway which might be responsible for different types of inherited and sporadic parkinsonism. This would lead to the identification of new therapeutic targets for interfering with disease progression. Although LB were originally described solely in PD, in the last decade these inclusions were described in a spectrum of degenerative disorders ranging from pure movement disorders to dementia. This suggests that common biochemical alterations leading to the formation of intracellular inclusions might underlie various pathological conditions. Consequently, the knowledge of the biochemical steps involved in the formation of neuronal inclusions could represent a key to develop new therapeutic strategies. In recent years it has been possible to develop both in vitro and in vivo neuronal inclusions resembling Lewy bodies. These experimental approaches have ranged from the use of alpha-synuclein transgenic mice to the continuous exposure to a mitochondrial complex I inhibitor. The aim of the present paper is to review briefly, recent advances on Lewy body research to achieve new insight into the etiology of PD and the molecular events leading to neurodegeneration.

Morphological and biochemical evidence that apomorphine rescues striatal dopamine terminals and prevents methamphetamine toxicity.

Apomorphine, given by a single injection, repeated injections, or by continuous infusion, was tested for neuroprotective effects in mice administered methamphetamine or N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in order to induce striatal dopamine (DA) depletion. In the first part of the study, the DA agonist (R)-apomorphine was administered at various doses (1, 5, and 10 mg/kg), 15 min before methamphetamine (5 mg/kg x 3, 2 h apart). Mice were sacrificed 5 days later. In the second part, apomorphine was administered either continuously by subcutaneous minipump (cumulative daily dose of 0.5, 1, and 3.15 mg/kg), or as single, repeated daily injections (up to 5 mg/kg) starting 40 h after an acute administration of MPTP (30 mg/kg). Mice were sacrificed at different time intervals (up to 1 month) following MPTP injection. In all the animals, the integrity of striatal DA terminals was evaluated by measuring striatal DA levels and TH immunohistochemistry. Apomorphine dose-dependently prevented methamphetamine toxicity. These effects were neither due to a decrease in the amount of striatal methamphetamine nor to the hypothermia, and they were not reversed by the DA antagonist haloperidol. Moreover, chronic, continuous (but not pulsatile) administration of apomorphine rescued damaged striatal dopaminergic terminals. These findings confirm a protective effect of apomorphine that also consists of a neurorescue of damaged striatal DA terminals. This suggests a new hypothesis about the long-term benefits observed during continuous apomorphine administration in Parkinson's disease patients.

Striatal postsynaptic ultrastructural alterations following methylenedioxymethamphetamine administration.

Amphetamine derivatives, such as methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA), act as monoaminergic neurotoxins in the central nervous system. Although there are slight differences in their mechanism of action, these compounds share a final common pathway, which involves dopamine release and oxidative stress. Apart from striatal toxicity involving monoamine axons, no previous report evidenced any alteration at the striatal level concerning postsynaptic sites. Given the potential toxicity for extracellular dopamine at the striatal level, and the hypothesis for neurotoxic effects of dopamine on striatal medium-sized neurons in Huntington's disease, we evaluated at an ultrastructural level the effects of MDMA on intrinsic striatal neurons of the mouse. In this study, administering MDMA, we noted ultrastructural alterations of striatal postsynaptic GABAergic cells consisting of neuronal inclusions shaped as whorls of concentric membranes. These whorls stained for ubiquitin but not for synuclein and represent the first morphologic correlate of striatal postsynaptic effects induced by MDMA.

Comparative analysis of senescent exorbital lacrimal glands in male and female albino rats.

In our previous study we described a bilateral-macroscopic and structural dimorphism of young rat exorbital lacrimal gland (Loewenthal's gland), which was the probable cause of the bibliographic discrepancies in the entity and the onset of its sexual dimorphism. Relevant literature also reported sex-dependent alterations in gland structure during senescence. The present study aims to carry out a comparative analysis on age-dependent changes in glands of both sides from male and female rats, using histological, histochemical and transmission electron microscopy, to evaluate whether the gland bilateral-macroscopic and structural dimorphism might influence the kind of alterations which occur in senescence. Our findings indicate that the macroscopic and structural side-specific dimorphism is not so evident in comparison with young rats. The side-specific dimorphism is evident only in male rats, in which the roundish gland appears to be more Sudan-positive in comparison with the ellipsoidal gland. The gland bilateral-macroscopic and structural dimorphism, although more evident in comparison with young animals, does not seem to influence these kinds of alterations due to senescence, a time-window in which we still observed some sexual differences also in more aged rats.