Reversal of somatostatin inhibition of AVP-induced cAMP by pertussis toxin

The effect of somatostatin on the stimulation of adenosine-3',5'-cyclic monophosphate (cAMP) production by arginine vasopressin (AVP) was examined in rat renal papillary collecting tubule cells in culture. The presence of phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine AVP at a concentration of 1 X 10(-10) M or higher significantly increased cellular cAMP levels in a dose-dependent manner. The stimulation by AVP of cellular cAMP production was significantly attenuated by 1 X 10(-6) M somatostatin (1 X 10(-9) M AVP, 477.5 +/- 23.0 vs. 292.4 +/- 28.5 fmol/micrograms protein per 10 min, P less than 0.01). When the cells were pretreated with pertussis toxin, pertussis toxin completely abolished the inhibitory effect of somatostatin on cellular cAMP production in response to AVP. Such an effect was obtained with a concentration of 0.1 ng/ml or higher of pertussis toxin and an incubation time of longer than an hour. The exposure of cells to 100 ng/ml pertussis toxin for two hours recovered the cellular cAMP response to 1 X 10(-9) M AVP in the presence of 1 X 10(-6) M somatostatin, the value of which 527.1 +/- 32.6 fmol/micrograms protein per 10 minutes, was a comparable level to that in response to only 1 X 10(-9) M AVP. Also, somatostatin inhibited the cellular cAMP response to glucagon and cholera toxin, but did not inhibit basal and forskolin-stimulated cAMP levels. Pertussis toxin treatment of cells completely abolished these inhibitory effects of somatostatin.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pulsatile secretion of gonadotropins and prolactin in male marathon runners. Relation to the endogenous opiate system

We tested the hypothesis that sustained, strenuous physical training alters the neuroendocrine regulation of pulsatile gonadotropin and/or prolactin secretion in men. Blood was sampled at 20-minute intervals over 8 hours in five endurance-trained men after a 10-15 mile run in the middle of the active training season, and in 11 nonendurance trained normal controls. In these two groups, basal patterns of physiologically pulsatile secretion of LH, FSH, and prolactin (PRL) were not significantly different in relation to the following parameters: mean serum concentration of each of the three hormones (N = 25 samples); areas under the hormone concentration vs. time curves; fractional, incremental, and absolute pulse amplitudes; and pulse frequency, or periodicity. To test for enhanced suppressive effects of endogenous opiates in trained male marathon runners, subjects were administered the potent opiate-receptor antagonist, naltrexone (1 mg/kg). This antagonist significantly stimulated pulsatile LH secretion by increasing mean serum LH values from 10.94 to 13.58 mIU/ml (P = 0.007); area under the LH concentration vs. time curve increased from 5370 to 6510 mIU/ml X 8 hours (P = 0.05) and, pulse frequency rose from 2.8 to 4.9 pulses/8 hours (P = 0.006). Naltrexone also enhanced pulse frequency of FSH secretion from 3.4 to 5.4 pulses/8 hours (P = 0.009), but did not alter serum prolactin concentrations. None of these responses differed significantly from those in normal sedentary controls.(ABSTRACT TRUNCATED AT 250 WORDS)     

1 alpha,25(OH)2D3 exerts cytostatic effects on murine osteosarcoma cells and enhances the cytocidal effects of anticancer drugs

The effects of 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25-(OH)2D3), 1 alpha-hydroxyvitamin D3 (1 alpha(OH)D3), and dexamethasone on colony formation of Dunn osteosarcoma cells (TA 102 cells) were investigated. Concentrations of 1 alpha,25(OH)2D3, 1 alpha(OH)D3, and dexamethasone at which they exerted 50% reduction of the total area of TA 102 colony formation were 9 X 10(-9) M, 9 X 10(-8) M, and 5 X 10(-6) M, respectively. Effects of anticancer drugs on TA 102 cells were also investigated and concentrations needed for 50% growth inhibition (50% inhibitory concentration values) of cis-platinum, mitomycin C (MMC), methotrexate (MTX), and Adriamycin (ADR) against TA 102 cells were calculated to be 0.07 microgram/ml, 0.0008 microgram/ml, 0.0008 microgram/ml, and 0.0005 microgram/ml, respectively. The simultaneous treatment of TA 102 cells with 10(-8) M of 1 alpha,25(OH)2D3 and anticancer drugs significantly enhanced the respective inhibitory effects on colony formation. In this treatment, the IC50 value of MMC was calculated to be 6.4 X 10(-6) micrograms/ml, which was 1/160 of the expected IC50 value of MMC (8 X 10(-4) micrograms/ml). Similar synergistic effects were observed when the cells were treated with 1 alpha,25(OH)2D3 and low concentrations of cis-platinum, MTX, or ADR.     

Interleukin-10 suppresses proliferation and remodeling of extracellular matrix of cultured human skin fibroblasts

When we previously examined the participation of local expression of interleukin-10 (IL-10) and tumor necrosis factor-alpha (TNFalpha) in wound healing of an intestinal anastomosis under septic conditions in mice, we found that IL-10 and TNFalpha expressions were markedly enhanced around the anastomosis and that wound healing was impaired in this animal model. The purpose of the present study was to investigate the combined effect of IL-10 on proliferation and remodeling of the extracellular matrix (ECM) of cultured human skin fibroblasts. Human skin fibroblasts were cultured for 48 h with IL-10 and/or TNFalpha at various concentrations, then the proliferation rates were determined using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The concentration of transforming growth factor-beta1 (TGFbeta1) in cell culture supernatants was measured by enzyme-linked immunosorbent assay, and type I collagen protein and matrix metalloproteinase-I (MMP-I) were detected by indirect immunofluorescence in cultured cells incubated for 48 h with 10 ng/ml of IL-10 and/or 10 ng/ml of TNFalpha. IL-10 itself had no effect on fibroblast proliferation, but reduced TNFalpha-induced fibroblast proliferation. The concentration of TGFbeta1 in cell culture supernatants was significantly lower in the presence of TNFalpha and IL-10 than in the presence of TNFalpha alone. Immunolabeling of fibroblasts for type I collagen protein was decreased in cells incubated with IL-10 and/or TNFalpha compared to controls. MMP-I immunolabeling was increased in cells incubated with IL-10, IL-10 and TNFalpha compared to control and cells incubated with TNFalpha. It is suggested that IL-10 is an inhibitory factor for the remodeling of the ECM during wound healing.     

人参皂甙Rb1促进大鼠雪旺细胞增殖的实验研究

目的：观察人参皂甙Rb1对体外培养的大鼠坐骨神经经雪旺经细胞增殖能力的影响，探讨其促进神经再生的作用机制。方法：取SD雄性大鼠坐骨骨神经体外培养第2代第5天，加入不同浓度的人参皂甙Rb1，利用MTT比色分析，^3H－胸腺嘧啶核甙测定法检测不同浓度人参皂甙Rb1在不同培养时间对体外培养大鼠旺细胞增殖的影响。结论：人参皂甙Rb1在10μg/ml的浓度对雪旺细胞增殖有明显促进作用，高浓度的人参皂甙Rb1 1mg/ml则显示抑制作用。而200μg/ml人参皂甙Rb1对细胞增殖的促进作用与对照组相近。结论：人参皂甙Rb1在适当浓度范围内可以促进雪旺细胞的增殖，从而为促进活体神经损伤的修复途径提供了一些研究基础。     

Sodium fluoride modulates caprine osteoblast proliferation and differentiation

The cellular and molecular pathways of fluoride toxicity in osteoblasts are not very well understood. Therefore, the objective of the present study was to evaluate the effects of sodium fluoride (NaF) on caprine osteoblasts cultured in vitro. Caprine osteoblasts at 2.0 x 10(-4) cells/ml were incubated in vitro with NaF at 0, 10(-8), 10(-7), 10(-6), 10(-5), 10(-4), 5.0 x 10(-4), and 10(-3) M, and then proliferation, differentiation, apoptosis, calcification, and alkaline phosphatase activity were examined. Also, the effect of NaF on osteoblastic cell viability and the molecular events leading to apoptosis were determined. Electron microscopy revealed cytoplasmic and nuclear alterations in the ultrastructure of osteoblasts exposed to various NaF concentrations. A cell-based quantitative evaluation of the MTT assay showed that NaF at concentrations of 10(-8) to 10(-5) M promoted cell proliferation, whereas at 10(-4) to 10(-3) M it suppressed cell proliferation and induced apoptosis. Alkaline phosphatase (ALP) activity and mineralization ability increased in cells treated at 10(-8) to 10(-5) M with sodium versus the controls, but decreased at 5.0 x 10(-4) to 10(-3) M dosage. The highest incidence of early apoptotic cells and late apoptotic cells was reached (3.33% and 2.92%, respectively) under NaF concentration of 10(-4) M. In conclusion, results of this study indicated that NaF modulates osteoblast proliferation and differentiation in a dose-dependent manner and modified osteoblast metabolism bidirectionally, suggesting NaF may play a significant role in osteoblast physiology.     

In Vitro Effects of Prolactin and Dexamethasone on Rat Leydig Cell Aromatase Activity

In Percoll purified adult rat Leydig cells, the estradiol secretion, in presence of exogenous testosterone (200 ng/ml) is stimulated 2-fold by either LH (100 ng/ml) or dbcAMP (1 mM). The addition of prolactin (1 microgram/ml) or dexamethasone (10(-7) M) to the Leydig cell incubation medium induces a 20% increase of the basal estradiol production, whereas, under LH or dbcAMP stimulations, 46 and 41% decreases are noted; moreover, a synergistic effect between prolactin and dexamethasone was observed in presence of dbcAMP leading to a 53% diminution of the estradiol synthesis. There results suggest that either hyperprolactinemia or high doses of glucocorticoids might inhibit the Leydig cell aromatase activity in presence of LH.     

酸性成纤维细胞生长因子及表皮生长因子对兔韧带细胞增殖的影响

目的：观察酸性成纤维细胞生长因子(aFGF)和表皮生长因子(EGF)对内侧副韧带(MCL)和前十字韧带(ACL)细胞增殖行为的影响。方法：培养10周龄新西兰白兔内侧副韧带和前十字韧带细胞，在培养液中分别加入aFGF和EGF，以XTT方法测定细胞的增殖行为。结果：aFGF在1ng／ml时即对两种细胞具有显著的促进增殖作用，其浓度达50ng／ml时，对MCL细胞的促进作用最大，达100ng／ml时对ACL细胞的促进作用最大。EGF在0．78ng／ml时即对MCL细胞有显著的促增殖作用，在1．56ng／ml时始对ACL细胞有显著的促增殖作用，其浓度达3．125ng／ml时对2种细胞的促进作用最大。aFGF和EGF在超过其最佳浓度后，随浓度升高促进作用均下降。结论：aFGF和EGF可以促进韧带成纤维细胞增殖。     

Effects of prolactin on explant cultures of rat ventral prostate: Morphological and immunohistochemical study

Specimens derived from rat ventral prostate were cultured by an explant culture technique using differents concentrations of ovine prolactin. Sacrified explants embedded on paraffin were sectioned for morphologic and immunocytochemical studies using antibodies against prostatic acid phosphatase, prostatic specific antigen, and wide-spectrum monoclonal keratin. Prolactin significantly stimulated the growth of these cells in the concentration range of 1 × 10^?2 ui/ml, but was inhibitory at a concentration of 1 and 0.1 ui/ml. The 1 × 10^?3 and 1 × 10^?4 ui/ml prolactin concentrations demonstrated the preservation of a glandular epithelium with a columnar shape, similar to the normal appearance of ventral prostate from rats. © 1993 Wiley-Liss, Inc.     

胰岛素样生长因子对体外培养豚鼠肋软骨细胞的影响

目的：了解胰岛素样生长因子(insulin-1ike growthfactor-1，IGF-1)对体外培养豚鼠肋软骨细胞分裂增殖及功能代谢的影响。方法：体外单层培养豚鼠肋软骨细胞，对照组培养液为无血流清DMEM，实验组在培养液DMEM中加入IGF-1使其终浓度分别为10ng／ml、50ng／ml、100ng／ml，作用6天后，检测细胞DNA含量和培养液中糖醛酸的含量。结果：IGF-1在10～100ng／ml浓度范围能明显增加培养软骨细胞的DNA及糖醛酸的含量，且以50ng／ml作用效果最明显，与对照组相比，有统计擘意义(P＜0．01)。结论：IGF-1对体外培养肋软骨细胞有刺激，并以剂量依赖性方式影响细胞的增殖及功能代谢。     

Vitamin E inhibits proliferation of primary cultured human mesangial and endothelial cells

BACKGROUND: Vitamin E (VE) has been used as an antioxidant and has been suggested to inhibit the proliferation of mesangial cells in rat and vascular endothelial cells. The direct effect of VE on primary cultures of mesangial cells (MC) and endothelial cells (EC) from the human glomerulus was studied. METHODS: (1) MC (in 17 or 2.5% FCS DMEM) or EC (in 10 or 5% FCS CSC) at 5,000 cells/well was incubated with serial concentrations of VE from 0.05 to 50 microg/ml (0.06 to 60 IU/l). (2) MC was cocultured with 160, 80, 40 or 20 microg/ml of low-density lipoprotein (LDL) or oxidized LDL (ox-LDL) in 17 or 2.5% FCS DMEM with or without VE. After 3 days of incubation at 37 degrees C in 5% CO(2), cell proliferation was measured by the Premix WST-1 Assay System. RESULTS: The concentration of VE that significantly inhibited the proliferation of MC cultured in 17 or 2.5% FCS DMEM was 50 or 2.5 microg/ml (60 or 3.0 IU/l), respectively, and that of EC in 10 or 5% FCS medium was 50 or 25 microg/ml (60 or 30 IU/l). VE at 25 microg/ml (30 IU/l) inhibited the LDL proliferative effect on MC cultured in 2.5 FCS DMEM by 21.79-93.21% in a LDL concentration-dependent manner. There was little difference between the effects of LDL and ox-LDL on the VE inhibitory effect on MC under our experimental conditions. CONCLUSION: VE at low concentrations had no effect on the proliferation of both MC and EC, but at high concentrations, it showed an inhibitory effect on both cells.     

表皮生长因子对子宫内膜细胞体外增殖的影响

本研究观察了表皮生长因子（ＥＧＦ）在体外对子宫内膜上皮细胞及基质细胞增殖的影响。采用酶消化加物理方法分离人子宫内膜上皮细胞及基质细胞,分别在体外培养,细胞汇合后消化,一部分用盖片法培养,用特异性抗体鉴定细胞纯度,另一部分做细胞增殖实验。在细胞中加入不同浓度的ＥＧＦ,培养２４、４８、７２小时,用ＭＴＴ法及流式细胞仪测定ＥＧＦ对子宫内膜上皮细胞及基质细胞增殖的作用。结果：ＥＧＦ浓度为５．０及１０．０ｎｇ／ｍｌ时,明显刺激子宫内膜上皮细胞及基质细胞的增殖,ＭＴＴ与流式细胞仪两法一致。ＥＧＦ不刺激细胞凋亡。结论：采用酶消化结合物理方法分离的人子宫内膜基质细胞及上皮细胞,方法简便、快速,细胞纯度高,在体外生长良好,可用于体外研究着床及异位子宫内膜生长的机制。当ＥＧＦ浓度为５．０及１０．０ｎｇ／ｍｌ时,确实刺激子宫内膜细胞的增殖。     

吡咯喹啉醌对许旺细胞增殖及c-fos、c-jun、CREB和PCNA表达的影响

目的 观察吡咯喹啉醌(PQQ)对许旺细胞(Sc)的增殖作用,并探讨其对Sc c-fos、c-jun、CREB及PCNA表达的影响.方法 体外原代培养、纯化及鉴定Sc;行无血清培养细胞周期同步化,应用不同浓度PQQ(0、1、10、100、1 000、10 000 nmol/L)作用sc 72 h;流式细胞仪检测细胞周期比例;RT-PCR检测c-fos、c-jun、CREB的mRNA含量;Western blot技术检测PCNA蛋白表达.结果 PQQ处理组表现为G0/G1期细胞比例减少,S期和G2/M期细胞所占比例增加;100 nmol/L PQQ可使c-fos、c-jun、CREB mRNA含量分别增加0.33、0.42和0.52倍(P＜0.05);PQQ浓度为1 000 nmol/L时,上述因子mRNA含量与对照组比较差异无统计学意义(P＞0.05);PQQ浓度为10 000 nmol/L时,上述因子mRNA的含量均降低(P＜0.05);PQQ浓度在1～100 nmol/L时,PCNA蛋白表达上调,且当PQQ浓度为100 nmol/L时PCNA蛋白上调效果最为明显,与对照组比较增加了1.17倍(P＜0.05);当PQQ浓度为1000 nmol/L时PCNA的表达与对照组比较差异无统计学意义(P＞0.05);当PQQ浓度为10 000 nmol/L时PCNA表达降低(P＜0.05).结论 10～100 nmol/L PQQ可促进Sc增殖,且c-fos、c-jun、CREB、PCNA在PQQ促Sc增殖过程中表达上调.

Abstract：

Objective To investigate the effects of pyrroloquinoline quinine ( PQQ ) on proliferation and expression of c-fos, c-jun, CREB and PCNA in cultured Schwann cells. Methods Schwann cells were cultured and purified in vitro. The purity of Schwann cells was identified by immunofluorescence of S-100. After synchronization of cell cycle by serum-free medium, different concentration of PQQ(0,1,10,100,1 000,10 000 nmol/L ) were added into culture medium for 72 h. Flow cytometry was used to determine cell cycle. The content of c-fos, c-jun, and CREB mRNA were detected by RT-PCR, and the expression of PCNA protein was detected by Western blot. Results After PQQ treatment, the percentage of cells in G0/G1 phase decreased and the percentage of cells in S and G2/M phase increased. After treated by PQQ at concentration of 1-10 000nmol/L, content of c-fos,c-jun, CREB mRNA was increased by 0. 33 , 0. 42 and 0. 52 fold (P＜0. 05 ) . However, at concentration of 1 000 nmo1/L, there was no difference in mRNAs content when compare to control(P ＞0. 05). And it showed a decline at concentration of 10 000 nmol/L(P＜0. 05). PCNA protein expression was up-regulated at PQQ concentration of 1-100 nmol/L. At 100 nmol/L, the expression increased by 1.17 fold (P＜ 0. 05 ) ; However, at 1 000 nmol/L, there was no difference in PCNA expression when compared to control. And 10 000 nmol/L of PQQ inhibited the expression of PCNA (P＜0. 05). Conclusions When treated with PQQ at concentration of 10-100 nmol/L, the proliferation of Schwann cells increased and the expression of c-fos,c-jun,CREB and PCNA was up-regulated.     

胰岛素样生长因子-Ⅰ对兔关节软骨细胞增殖及代谢的影响

目的　探讨胰岛素样生长因子 - (IGF- )对体外生长的关节软骨细胞分裂增殖及功能代谢的影响。方法　采用体外单层培养的方法 ,应用兔关节软骨细胞 ,对照组培养液为 10 %小牛血清 DMEM,实验组在培养液DMEM中加入 IGF- 使其终浓度分别为 3、10、30、10 0及 30 0 ng/ ml,作用细胞 2、4和 6天 ,检测细胞 DNA含量和基质中糖醛酸的含量。结果　 IGF- 在 3～ 30 0 ng/ ml浓度范围能明显增加培养软骨细胞的 DNA及糖醛酸的含量 ,且以30～ 10 0 ng/ ml作用 4天刺激效果最明显 ,与对照组相比 ,有统计学意义 (P<0 .0 1)。结论　 IGF- 对体外培养软骨细胞有刺激 ,并以剂量时间依赖性方式影响增殖及功能代谢。     

The effect of oxytocin on cell proliferation in the human prostate is modulated by gonadal steroids: implications for benign prostatic hyperplasia and carcinoma of the prostate

BACKGROUND: Oxytocin (OT) is implicated in regulating prostate growth. OT concentrations are increased in benign, and decreased in malignant prostate disease. This study investigated whether the altered concentrations of OT present in prostate disease affect the proliferation of malignant and non-malignant human prostate cells. METHODS: The effects of varying concentrations of OT and gonadal steroids on cell proliferation of non-malignant prostatic epithelial (PrEC) and stromal (PrSC) cells and androgen dependent (LNCaP) and independent (PC-3) malignant cell lines were assessed. RESULTS: OT (>0.5 nmol . L(-1)) had no effect on PrEC proliferation when cells were cultured alone. When co-cultured with PrSC and gonadal steroids, OT inhibited epithelial cell proliferation. OT inhibited PrSC proliferation, when cells were cultured alone. When PrSC were co-cultured in the presence of estrogen physiological concentrations of OT were inhibitory. No effect on cell proliferation was observed with higher concentrations of OT. OT did not affect the proliferation of malignant cell lines in the absence of androgens but, in the presence of testosterone, low concentrations of OT (<1 nmol . L(-1)) stimulated proliferation of PC-3 cells. Disruption of caveolae in the plasma membrane removed the inhibitory effect of OT on PrSC proliferation but did not affect the stimulatory effect of OT on PC-3 cells cultured in the presence of androgens. CONCLUSIONS: Changes in prostatic concentrations of OT that occur with aging and malignant disease may act to facilitate cell proliferation. The localization of the OT receptor within the plasma membrane modulates OT's proliferative response in the prostate.     

血小板源性生长因子BB对体外培养肌腱细胞增殖的影响

Objective To study the effect of platelet-derived growth factor-BB (PDGF-BB) in dif-ferent concentrations on proliferation of tendon cells cultured in vitro. Methods Rat tendon cells were cultured and identified in vitro. The rat tendon cells were cultured in PDGF-BB nutrient solution in different concentrations. They were then divided into 1, 5, 10, 20, 50, 100, 150, 200, 250 ng/mL PDGF-BB groups (cultured with 0.1 mL 0.5% PBS with addition of 1, 5, 10, 20, 50, 100, 150, 200, 250 ng/mL PDGF-BB respectively). Tendon cells in control group were cultured with 0.1 mL 0.5% FBS. Proliferation of tendon cells was detected by MTT test. The absorbance values of tendon cells in control group and 20 ng/mL PDGF-BB group before culture and after cultured for 12, 24, 36, 48, 60, 72 hs were determined. Results The isolated cells were identified to be rat tendon cells as they were Type Ⅰ collagen staining posi-tive and Type Ⅲ collagen staining negative. Compared with that of control group, the absorbance values of other groups were all increased, except for that of 250 ng/mL PDGF-BB group (P<0.05 or P<0.01). Besides, the absorbance value rose gradually with the increase of the concentration of PDGF-BB on, and then diminished gradually with the increase of the concentration of PDGF-BB from 20 ng/mL on. Tendon cells in 20 ng/ml PDGF-BB group began to increase in number when cultured for 12 hs, and it reached the highest level (0.53±0.04) at 48 h, which were obviously higher than those of control group at 24-72 h (P<0.01). The absorbance value of tendon cells in 20 ng/mL PDGF-BB group was significantly higher than that of control group at 24, 36, 48, 60, 72 h after culture (P<0.01 ). Conclusions PDGF-BB can promote the proliferation of tendon cells in a definite range of concentration and time.     

4-羟基他莫昔芬对前列腺基质细胞增殖与凋亡的作用

目的:研究4-羟基他莫昔芬(OHT)对原代培养的前列腺基质细胞增殖与凋亡的影响。方法:以10-8~10-5mol/L的雌二醇(E2)、己烯雌酚(DES)、OHT以及10-8~10-6mol/L的E2与10-7mol/L的OHT混合物分别作用于原代培养的前列腺基质细胞,采用MTT法和TUNEL法分别检测细胞增殖和凋亡。结果:OHT对前列腺基质细胞增殖和凋亡的作用与E2和DES比较均有显著差异(P均<0.05),在10-7~10-5mol/L浓度下表现出与浓度相关(r=-0.383,P=0.005)的抑制增殖作用(P<0.05),10-7mol/L的OHT可以抑制相同甚至更高浓度(10-6mol/L)E2的促增殖作用(P<0.05);OHT在10-8~10-5mol/L浓度下显示与浓度相关(r=0.349,P=0.012)的促凋亡作用(P<0.05),且10-7mol/L OHT的促凋亡作用不能被相同甚至更高浓度(10-6mol/L)E2所逆转(P>0.05)。结论:OHT在一定浓度范围内对原代培养的前列腺基质细胞具有明显的抑制增殖和促凋亡作用,该作用可能不完全是通过竞争性抑制雌激素受体而实现的。     

EGF和IGF对体外培养兔关节软骨细胞的影响

目的　了解表皮生长因子 (EGF)和胰岛素样生长因子 (IGF)对体外培养兔关节软骨细胞存活数目和分裂增殖百分数的影响。方法　体外培养兔关节软骨细胞传至第 2代 ,分别以EGF、IGF ,以及二者不同的浓度组合作用于软骨细胞。通过酶联免疫检测仪 (MTT)测定软骨细胞存活数 ,流式细胞仪测定软骨细胞分裂增殖百分数。结果　不同浓度EGF对兔关节软骨细胞存活和分裂增殖均有促进作用 ,作用浓度强度次序为 :10ng/ml>0 1ng/ml>10 0ng/ml。不同浓度IGF对兔关节软骨细胞的存活和分裂增殖均有较强促进作用 ,浓度为 5 0ng/ml时 ,刺激效果最显著。EGF与IGF联合使用时 ,刺激效果优于任何一种因子单独使用 ,而以EGF 10ng/ml和IGF 5 0ng/ml为最佳浓度组合。 结论　EGF和IGF都可促进兔关节软骨细胞存活和分裂增殖 ,但以协同作用效果最佳。     

降钙素对体外培养成骨细胞增殖的影响

目的　观察降钙素对体外培养成骨细胞增殖的影响。方法　降钙素与成骨细胞体外共同培养 3d ,采用MTT法 ,检测成骨细胞的增殖情况。用地塞米松作为阳性对照药。结果　除 1mIU L组 ,降钙素其他浓度组均能促进成骨细胞增殖 (P <0 0 5或P <0 0 0 1) ,各组间作用差异无显著性。但在 10～ 10 0mIU L范围内 ,作用强度随剂量上升有增强趋势。地塞米松各浓度均能促进成骨细胞增殖 ,并显示一定的浓度依赖性。结论　降钙素能促进体外培养成骨细胞增殖 ,使成骨细胞数量不断上升。这可能是降钙素治疗骨质疏松症的机制之一。