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Bisphenol A (BPA), an endocrine-disrupting chemical, is capable of producing reproductive toxicity. BPA results in mitochondrial DNA (mtDNA) deletion and mitochondrial dysfunction; however, the effect of BPA on the mitochondria of ovarian granulosa cells is not clear. Further, 1,25-dihydroxyvitamin D3 (1,25D3) may play a role in reproduction, because its receptor, VDR, contributes to the inhibition of oxidative stress and predominantly exists in the nuclei of granulosa cells. Hence, the role of 1,25D3 in BPA-mediated effects on mitochondrial function was examined in this study. Primary rat granulosa cells treated with BPA, 1,25D3, or both were subjected to molecular/biochemical assays to measure cell survival, mtDNA content, mtDNA deletion, superoxide dismutase activity, levels of proteins related to mitochondrial biogenesis, and mitochondrial function. We found that cell viability was dose-dependently reduced and reactive oxygen species (ROS) levels were increased by BPA treatment. BPA administration elevated Mn-superoxide dismutase (MnSOD) expression but negatively regulated total SOD activity. 1,25D3 treatment alone increased 17β-estradiol secretion, ATP production, and cellular oxygen consumption. In cells treated with both agents, 1,25D3 enhanced BPA-induced MnSOD protein upregulation and blocked the BPA-mediated decline in total SOD activity. Furthermore, 1,25D3 attenuated BPA-mediated mtDNA deletion but showed no effect on BPA-induced increases in mtDNA content. Although BPA had no influence on the levels of peroxisome proliferator-activated receptor-γ coactivator-1 α, nuclear respiratory factor-1, mitochondrial transcription factor A, or cytochrome c oxidase subunit IV, 1,25D3 plus BPA markedly increased mitochondrial biogenesis-related protein expression via the PI3K-Akt pathway. Moreover, BPA-mediated negative regulation of cytochrome c oxidase subunit I levels and 17β-estradiol secretion was attenuated by 1,25D3 pre-treatment. Our results suggest that 1,25D3 attenuates BPA-induced decreases in 17β-estradiol and that treatment with 1,25D3 plus BPA regulates granulosa cell mitochondria by elevating mitochondrial biogenesis-related protein levels.

Background/purpose We previously showed that subsequent intrathecal (i.t.) injection of resveratrol (30 μg) significantly reverses morphine-evoked neuroinflammation in morphine-tolerant rats. The present study examined the underlying mechanism. Methods Male Wistar rats were implanted with two i.t. catheters, one of which was connected to a miniosmotic pump and used for morphine (15 μg/h) or saline infusion for 120 hours. To examine the effects on spinal cord expression of histone deacetylase 1 (HDAC1), the inflammatory cytokine tumor necrosis factor-α (TNF-α), and TNF receptor (TNFR) 1 and TNFR2 during tolerance induction, a tail-flick test was performed prior to infusion and after 24 hours, 48 hours, 72 hours, 96 hours, and 120 hours of infusion. Results Resveratrol treatment prior to morphine challenge restored the antinociceptive effect of morphine in morphine-tolerant rats and reversed the morphine infusion-induced increase in HDAC1, TNF-α, and TNFR1 expression. Moreover, chronic morphine infusion increased TNFR1-specific expression in neuron in morphine-tolerant rat spinal cords, and this effect was almost completely inhibited by resveratrol treatment prior to morphine challenge. Conclusion Resveratrol restores the antinociceptive effect of morphine by reversing morphine infusion-induced spinal cord neuroinflammation and increase in TNFR1 expression. The reversal of the morphine-induced increase in TNFR1 expression by resveratrol is partially due to reversal of the morphine infusion-induced increase in HDAC1 expression. Resveratrol pretreatment can be used as an adjuvant in clinical pain management for patients who need long-term morphine treatment or with neuropathic pain.

In recent years, 3D endoscopic imaging has played an important role in the development of the medical industry, making it easy for medical doctors to judge the visual depth of ulcers or tumors and thereby decreasing the risk of unnecessary damages to other tissues. A traditional 2D endoscopic image can be converted into a 3D view through depth estimation and the use of a depth image-based rendering method. However, the application of depth estimation may be too time-consuming for use with current medical equipment. With the current equipment, the estimated depth map may also be drastically altered, causing the converted view to have unavoidable defects such as geometric distortion and hole effects. As a result of these dramatic changes, the depth map will have holes of different sizes and directions. Therefore, this paper presents the techniques of hierarchical similarity analysis and content-adaptive filtering as a means to transform the 2D image into a 3D view quickly and precisely. In order to reduce the computing time, this paper adopts hierarchical similarity analysis to separate images into different sizes in order to analyze the similarity and depth information estimation. After depth map estimation, a preprocessing procedure that applies respective Gaussian filters to different sizes and directions of holes is used to achieve the optimization of the depth map. As a result, this method not only reduces the system computation time, making it appropriate for use with current medical equipment, but also improves the 3D view quality for medical doctors.

Bisphenol A (BPA), an endocrine-disrupting chemical, is capable of producing reproductive toxicity. BPA results in mitochondrial DNA (mtDNA) deletion and mitochondrial dysfunction; however, the effect of BPA on the mitochondria of ovarian granulosa cells is not clear. Further, 1,25-dihydroxyvitamin D

The medical image segmentation technology is quite a challenging and complicated research. Generally, an X-ray image is often giving significant information of hard tissue pathology within most assessments. Compared with medical images of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI), the advantages of X-ray imaging are inexpensive, and it is widely attempted in most of the medical examinations. The X-ray imaging has been intensively applied on clinical bone diagnostics nowadays. However, the X-ray imaging still has several drawbacks on clarifying its images when radiation intensities exposed unevenly on the examined subject. For example, on a hand X-ray image, if the image has received unequal X-ray strengths, the final image would be inexplicable to separate soft tissues. In this work, we use the technique of a statistical parametric contour with threshold X-ray image segmentation technology to overcome those drawbacks of the X-ray images. By using this approach, we can successfully separate bone from muscle tissues of hand.

Background/purpose As known, long-term morphine infusion leads to tolerance. We previously demonstrated that both co-infusion and post-administration of ultra-low dose (±)-naloxone restores the antinociceptive effect of morphine in morphine-tolerant rats. However, whether the mechanism of the action of ultra-low dose (±)-naloxone is through opioid receptors or not. Therefore, in the present study, we further investigated the effect of ultra-low dose (+)-naloxone, it does not bind to opioid receptors, on the antinociceptive effect of morphine. Methods Male Wistar rats were implanted with one or two intrathecal (i.t.) catheters; one catheter was connected to a mini-osmotic pump, used for morphine (15 μg/h), ultra-low dose (+)-naloxone (15 pg/h), morphine plus ultra-low dose (+)-naloxone (15 pg/h) or saline (1 μl/h) infusion for 5 days. On day 5, either ultra-low dose (+)-naloxone (15 pg) or saline (5 μl) was injected via the other catheter immediately after discontinued morphine or saline infusion. Three hours later, morphine (15 μg in 5 μl saline) or saline were given intrathecally. All rats received nociceptive tail-flick test every 30 minutes for 120 minutes after morphine challenge at different temperature (45–52°C, respective). Results Our results showed that, both co-infusion and post-treatment of ultra-low dose (+)-naloxone with morphine preserves the antinociceptive effect of morphine. Moreover, in the post administration rats, ultra-low dose (+)-naloxone further enhances the antinociceptive effect of morphine. Conclusion This study provides an evidence for ultra-low dose (+)-naloxone as a therapeutic adjuvant for patients who need long-term opioid administration for pain management.

3D endoscopic imaging has played an important role in the development of the medical industry, making it easy for medical doctors to judge the visual depth of ulcers or tumors and thereby decreasing the risk of unnecessary damages to other tissues. A traditional 2D endoscopic image can be converted into a 3D view through depth estimation and the use of a Depth Image-Based Rendering (DIBR) method. However, the application of depth estimation may be too time-consuming for use with current medical equipment. In order to reduce the computing time, this work adopts hierarchical similarity analysis to separate images into different sizes in order to analyze the similarity and depth information estimation. As a result, this method not only reduces the system computation time, making it appropriate for use with current medical equipment, but also provide a good 3D view for medical doctors.

Background: The heart is a highly vascular organ and prolonged interruption of myocardial blood flow initiates events that culminate in cardiac myocyte death. Proposed experimental reparative strategies include harvesting potent cells followed by direct injection into ischemic myocardium to achieve myogenesis and angiogenesis. Methods: Accordingly, we set out to isolate and expand a purified population of adult rat putative cardiomyocyte precursors, and to identify their characteristics in vitro. By using an acute myocardial infarction model and direct cell implantation, we further tested the hypothesis that these cells are an ideal cell source for myocardial regeneration and can enhance cardiac repair after implantation into the ischemic rat heart. Results: We describe here the identification of a subpopulation of primitive cells from rat heart, processing stem cell marker, c-kit and myogenic transcriptional factors, GATA-4 and MEF 2C, and cardiac specific proteins, troponin-I, α-sarcomeric actinin and connexin-43. They exhibited a high in vitro proliferative potential. These findings strongly suggest that these cells are putative cardiomyocyte precursors. After transplantation, they were able to be retained and proliferate (13.63 ± 5.97% after 2 weeks) within the ischemic heart. Progeny of implanted cells migrated along the infarcted scar, reconstituted regenerated cardiomyocytes with incorporation into host myocardium, and inhibited cardiac remodeling with decreased scar formation. Conclusion: Our findings suggest that putative cardiomyocyte precursors isolated from adult heart could potentially be an autologous cell source for myocardial regeneration cell therapy. [J Chin Med Assoc 2008;71(2):79–85]

AgCl coated Ag foil has been widely used as the biopotential sensor to diagnose problems of the human heart. Evidence shows that quality of AgCl on the electrode could experience degradation during the process of long-term monitoring for irregular activities of the heart. To study the degradation of AgCl/Ag electrode, new and used electrodes were collected. Electrochemical tests such as open-circuit potential (OCP), cathodic stripping, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and X-ray mapping of elemental distribution were applied to understand the electrochemical properties of the sensors during the progress of degradation. Results revealed that OCP values shift from positive potential of new sensor to negative potential of used sensor (OCP(new): +30 mV; OCP(used): -300 mV, p < 0.05) and a significant difference in impedance (Impedance(new): 3000 Omega; Impedance(used): 1 MOmega, p < 0.05). Ratio of the average AgCl thickness on good and bad eletrocardiographic (ECG or EKG) electrodes is 4.83 (p < 0.05). Simulated degradation by exposing the biosensor to deaerated sweat solution and by cathodic stripping of AgCl proposed that the degradation occurs by cathodic reduction of AgCl due to the presence of hydrogen ions in the low pH value of human sweat under deaerated condition.

Passivated 316L stainless steel is used extensively in cardiovascular stents. The degree of chloride ion attack might increase as the oxide film on the implant degrades from exposure to physiological fluid. Stability of 316L stainless steel stent is a function of the concentration of hydrated and hydrolyated oxide concentration inside the passivated film. A high concentration of hydrated and hydrolyated oxide inside the passivated oxide film is required to maintain the integrity of the passivated oxide film, reduce the chance of chloride ion attack, and prevent any possible leaching of positively charged ions into the surrounding tissue that accelerate the inflammatory process. Leaching of metallic ions from corroded implant surface into surrounding tissue was confirmed by the X-ray mapping technique. The degree of thrombi weight percentage [Wao: (2.1 ± 0.9)%; Wep: (12.5 ± 4.9)%, p < 0.01] between the amorphous oxide (AO) and the electropolishing (EP) treatment groups was statistically significant in ex-vivo extracorporeal thrombosis experiment of mongrel dog. The thickness of neointima (Tao: 100 ± 20 μm; Tep: 500 ± 150 μm, p < 0.01) and the area ratio of intimal response at 4 weeks (ARao: 0.62 ± 0.22; ARep: 1.15 ± 0.42, p < 0.001) on the implanted iliac stents of New Zealand rabbit could be a function of the oxide properties. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006

Taiwan has been entering an aging society, with the issue of taking care of the elderly being more and more severe. Although many home care systems have come out being sold in the market, there’s still a long way to develop a Tele-health care system in order to let the elderly use it efficaciously away from their home. The approaching of massive data era drives the cloud computing being popular, and our government also take action to integrate the database of National Health Insurance Research, establishing The Big Data for Health Care. All they want is to bring more benefits to health care. This research take purpose to propose an early warning process with return of initiative judging whether the device return correctly; we will construct a micro mobile care system as well, judging users’ health condition efficaciously by association rule, completing the timely informing, helping the elderly to achieve a better life, reducing the waste of medical resource.

Vasopressin (AVP) stimulates the absorption of Na+ across frog skin epithelium by increasing the number of open apical channels (No) mainly through a large expansion of the total number of channels (NT) at the membrane. This study investigates with blocker-induced noise analysis the potential role of actin in the regulation of AVP-induced changes in channel densities. Particularly we examined the idea that actin regulates the insertion of channels into apical cell membranes, consistent with the model for its hydrosmotic action. Treating cells with cytochalasin B (CB) for 2 h to disassemble the prominent subapical actin network did not significantly alter the stimulation of the Isc by AVP. Importantly, the treatment had no significant effect on the AVP-induced activation of Na+ channels, nor on the increases in NT indicating that an intact actin network is not required for the natriferic actions on the channels. This result is disparate from well known effects of CB on the AVP-induced hydrosmotic response and we assume that these distinct responses are produced by different mechanisms. Other mechanisms need to be considered to explain the mechanism whereby new Na+ channels are recruited to the apical membrane. In particular, mechanisms of intracellular trafficking involved in the redistribution of epithelial Na+ channels remain unresolved and need to be refined.

The accelerated aging population around the world will be more obvious. In the USA, there will be about 72 million people aged 65 by 2030, There will have nearly 36.98% of the elderly population in Taiwan until 2050. Those people will need health care too. Nowadays, the current health care focus on the passive home care in Taiwan, however, the devices which can provide elder to carrying in outdoor will be huge and heavy, and also the devices will hard to actively send the alert message for the medical units when the patient have problem in their health. Therefore, the proposed of this study is to miniaturized vital sign detection and active alert system. The system will give elder the privacy, convenience, and security as well. Hoping this study can not only reduce the medical unit's work but lower the medical resources cost, moreover, it will also enhance the quality of life for the patients.

Aortic aneurysm is caused by sclerosis of aortic wall. However, bad habits and chronic disease would be caused sclerosis of aortic wall. Therefore, bad habits and chronic diseases would possible affect aortic aneurysm, even after surgery. In this study, we used data mining to analyzed patient's history and lab data from pre-operation and post-operation to find the affect between aortic aneurysm and chronic disease. Then, we could be aimed difference of aortic aneurysm patient's chronic disease to let the patient to prevent or treat status early. Furthermore, it increased aortic aneurysm patient the effect of recovery after operator.

Background/Purpose In a recent study, we found that baicalin exhibited a potent analgesic effect on carrageenan-evoked thermal hyperalgesia. The underlining mechanisms may be associated with inhibition of inflammatory mediator overproduction, including proinflammatory cytokines, nitric oxide (NO), and prostaglandin E2 (PGE2). In the present study, we examined the effect of baicalin on the antinociceptive effect of morphine and histone deacetylase 1 (HDAC1) expression in the spinal cord dorsal horn in neuropathic pain rats. Methods Neuropathic pain was induced by tight ligation of the left L5 spinal nerve of the rats. An intrathecal catheter was implanted for drug administration. Nociception was assessed by using the plantar test with the Hargreaves radiant heat apparatus, and the von Frey test with the dynamic plantar anesthesiometer. Spinal cords were removed for histone acetyl-H3 and HDAC1 western blot analysis at the end of the nociceptive assessment. Results The results showed that hyperalgesia and allodynia were observed in the spinal nerve ligated (SNL) left hindlimb; it was companied by histone-H3 deacetylation and HDAC1 overexpression on the ipsilateral side of the spinal cord dorsal horn. Intrathecal injection of baicalin (10 μg) significantly attenuated the allodynia and hyperalgesia, and enhanced the antinociceptive effect of morphine (15 μg). Moreover, baicalin reversed the histone-H3 acetylation and suppressed HDAC1 expression on the ipsilateral side of the spinal cord dorsal horn of SNL rats. Conclusion The present findings suggest that baicalin can ameliorate neuropathic pain by suppressing HDAC1 expression and preventing histone-H3 acetylation in the spinal cord dorsal horn of SNL rats.

Microfilaments were localised by immunofluorescence and immunogold cytochemistry to examine their distribution in granular cells of the isolated frog skin epithelium. Strongly fluorescent bundles of actin were observed beneath the plasma membrane with little evidence for actin in the central regions. Higher resolution offered by cytochemistry revealed that bundles of actin filaments comprised a substantial portion of the cortical cytoskeleton. Quantitative analysis of the frequency of gold label revealed an extremely rich array of filaments beneath the apical membrane of granular cells, with markedly less label along the basolateral membrane and in the central cytoplasm. Treating cells with cytochalasin B or arginine vasopressin caused an apparent disruption of the apical actin fibres, concurrent with a decrease in gold label density. Assumably these signs are indicative of depolymerization of the filaments. Although the significance of this distribution is unknown, the apical polarisation of actin is consistent with a role in regulating the Na+ permeability of the apical membrane. The data are discussed in relation to possible roles of the cytoskeleton in the regulation of transepithelial sodium transport by vasopressin.

Background In the present study, we examined the effects and mechanisms of the Chinese herb resveratrol on attenuation of morphine tolerance in rats. Methods Male Wistar rats were implanted with 2 intrathecal catheters; one catheter was connected to a mini-osmotic pump, used for either morphine (15 μg/h) or saline (1 μL/h) infusion for 5 days. On day 5, resveratrol (7.5, 15, 30, or 60 μg), dimethyl sulfoxide (5 μL), or saline (5 μL) was injected via the other catheter immediately after the discontinued morphine infusion. Three hours later, intrathecal morphine (15 μg in 5 μL saline) was given. All rats received the nociceptive tail-flick test every 30 minutes for 120 minutes after the morphine challenge. Results Long-term morphine infusion induced antinociceptive tolerance and up-regulated N-methyl-D-aspartate receptor (NMDAR) subunit NR1 and NR2B expression in the synaptosome fraction of the tolerant spinal cord dorsal horn. Resveratrol pretreatment provided a significant antinociceptive effect of morphine in morphine-tolerant rats, and it was associated with reversal of the up-regulated NR1 and NR2B subunits in the synaptosome fraction of morphine-tolerant rat spinal cords. NR1/NR2B-specific antagonist ifenprodil treatment produced a similar effect as that of resveratrol. Furthermore, an increase of postsynaptic density-95/NR1/NR2B complex immunoprecipitation in morphine-tolerant rat spinal cord was also inhibited by resveratrol pretreatment. Moreover, chronic morphine infusion activated glial cells with an increase of proinflammatory cytokine tumor necrosis factor-α, interleukin-1β, and interleukin-6 mRNA expression in morphine-tolerant rat spinal cords and these effects were suppressed by resveratrol pretreatment before the morphine challenge. Conclusions Resveratrol attenuates morphine tolerance by inhibiting neuroinflammation and down-regulating NMDAR NR1 and NR2B subunit expression. Resveratrol regulates the NMDAR expression, which might be involved in a loss of scaffolding postsynaptic density-95 protein.

1. A weak electroneutral sodium channel blocker 6-chloro-3,5-diamino-pyrazine-2-carboxamide was used to perform noise analysis on isolated epithelium from Rana fuscigula to determine the cellular mechanism underlying autoregulation of Na+ channel densities in response to a reduction in the mucosal Na+ concentration. 2. The inherent transport rates of these tissues were generally lower than in other frog skins. The macroscopic sodium current, INa, averaged 10.71 microA/cm2 and was mainly determined by the number of open channels (N(o)) which averaged 21.6 million/cm2. The calculated mean channel open probability (beta') was 0.38, and corresponded very closely to values previously determined by patch clamp. 3. Reducing the mucosal Na+ from 110 to 10 mM caused large increases in the open channel density, which stabilized the Na+ transport rate. N(o) increased from a mean value of 26.6 to 64.3 million/cm2 within 2 min. 4. Autoregulatory changes were induced primarily by increasing beta' by about 60% and to a lesser extent by an increase in NT, the total number of open and closed channels. 5. We also examined the role of the cytoskeleton in the regulation of Na+ channel densities. Colchicine treatment, which disrupted microtubules, had no apparent effect on the ability of the tissues to autoregulate their Na+ channel densities. 6. The integrity of the microfilaments were essential for autoregulatory changes in N(o). After we had disrupted the microfilaments with cytochalasin B, we observed a marked reduction in the ability of the tissues to increase N(o). 7. The mean N(o) did not increase in response to a drop in mucosal Na+ despite the fact that beta' increased by 69%. We, therefore, assumed that cytochalasin B did not affect Na+ channels already present in the membrane but interfered with recruitment of new channels. Significantly, we did not observe any increase in NT. 8. In kidney and other tight epithelia, microfilaments are responsible for regulating the delivery of newly synthesized membrane proteins. We believe that our results with cytochalasin-treated tissues support the theory that autoregulatory changes in N(o) are also regulated by the recruitment of channels from a cytoplasmic pool.

The inert properties of gold make it a useful material for implants. Gold was applied as a coating on 316L stainless steel stents to improve the radiopacity and to provide better thrombogenic resistance and a lower degree of restenosis after deployment. Reports of clinical trials using gold-coated stents showed controversial results. A detailed examination of gold-coated stents was designed to understand the influence of surface conditions on the electrochemical properties in vitro. Corrosion resistance of gold-coated stents was investigated by cyclic polarization, and potentiostatic control. Surface morphologies of gold-coated stents in as-received condition, postinflated condition, and after cyclic polarization were characterized by scanning electron spectroscopy (SES). X-ray mapping identified elemental distribution. Results found severe defects in the gold-coating in the as-received condition, cracks and wrinkles on inflated gold-coated stents, and severe corrosion after cyclic polarization. Leaching of metallic ions in Ringer's solution was possible.

For years, MP35N alloy has been regarded as a very high corrosion-resistant material and has been widely used in various medical applications such as orthopedic implants, lead wire for pacemakers, and cardiovascular stents. Previous researchers of this alloy revealed corrosion pits or localized oxidation on the surface of this material after exposure to Ringer's solution. Therefore, a detailed examination of this multiphase alloy was designed to understand its electrochemical properties and to explore its corrosion behavior. Corrosion resistance of MP35N was investigated by open-circuit potential, anodic polarization, potentiostatic control, electrochemical impedance spectroscopy, and linear voltammetry techniques. Compositional studies of oxide film were examined by electron spectroscopy for chemical analysis. Surface morphologies of MP35N after electrochemical studies were characterized by scanning electron spectroscopy. Elemental distribution and chemical composition was identified by energy dispersive spectrum. Results indicate that chemical composition of the oxide film after passivation plays an important role in the determination of corrosion resistance of MP35N in Ringer's solution. A high concentration of hydroxyl and hydrate groups inside the passivated oxide film is beneficial to the corrosion resistance of this multiphase alloy.

Background Aromatase converts testosterone into 17beta-estradiol in granulosa cells, and the converted 17beta-estradiol contributes to follicular maturation. Additionally, excessive testosterone inhibits aromatase activity, which can lead to concerns regarding polycystic ovary syndrome (PCOS). Generally, 1,25-dihydroxyvitamin D3 (1,25D3) supplements help to improve the symptoms of PCOS patients who exhibit low blood levels of 1,25D3. Therefore, this study investigated the interaction effects of 1,25D3 and testosterone on estrogenesis and intercellular connections in rat granulosa cells. Methods Primary cultures of granulosa cells were treated with testosterone or testosterone plus 1,25D3, or pre-treated with a calcium channel blocker or calcium chelator. Cell lysates were subjected to western blot analysis to determine protein and phosphorylation levels, and 17beta-estradiol secretion was examined using a radioimmunoassay technique. Cell viability was evaluated by MTT reduction assay. Connexin 43 (Cx43) mRNA and protein expression levels were assessed by qRT-PCR, western blot, and immunocytochemistry. Results Testosterone treatment (0.1 and 1 microg/mL) increased aromatase expression and 17beta-estradiol secretion, and the addition of 1,25D3 attenuated testosterone (1 microg/mL)-induced aromatase expression but improved testosterone-induced 17beta-estradiol secretion. Furthermore, testosterone-induced aromatase phosphotyrosine levels increased at 10 min, 30 min and 1 h, whereas 1,25D3 increased the longevity of the testosterone effect to 6 h and 24 h. Within 18–24 h of treatment, 1,25D3 markedly enhanced testosterone-induced 17beta-estradiol secretion. Additionally, pre-treatment with a calcium channel blocker nifedipine or an intracellular calcium chelator BAPTA-AM reduced 1,25D3 and testosterone-induced 17beta-estradiol secretion. Groups that underwent testosterone treatment exhibited significantly increased estradiol receptor beta expression levels, which were not affected by 1,25D3. Neither testosterone nor 1,25D3 altered 1,25D3 receptor expression. Finally, at high doses of testosterone, Cx43 protein expression was decreased in granulosa cells, and this effect was reversed by co-treatment with 1,25D3. Conclusions These data suggest that 1,25D3 potentially increases testosterone-induced 17beta-estradiol secretion by regulating aromatase phosphotyrosine levels, and calcium increase is involved in both 1,25D3 and testosterone-induced 17beta-estradiol secretion. 1,25D3 reverses the inhibitory effect of testosterone on Cx43 expression in granulosa cells.