Biomedical subjects

T Harada

Publications and source records attributed to T Harada.

At least 271 records · Page 15Linked to original sources

PubMed1998

Granulocyte-colony stimulating factor improves suppressed neutrophilic phagocytosis against hypernatremic condition.

Phagocytic activity is an important function of neutrophils in the host defense against burn wound infection. In a previous report we demonstrated hypernatremic suppression of neutrophils at sodium concentrations comparable to these in the zone of stasis in the burn wound. At this site the osmotic pressure will be elevated as a result of several factors, especially to increased water loss from the burn wound surface. In this study the effect of granulocyte-colony stimulating factor (G-CSF) on phagocytic activity of human neutrophils against hypernatremic suppression is investigated in vitro. In the G-CSF group 150 ng of G-CSF was added to four blood samples (5 ml each). Phagocytic activities of the control group (n = 10) showed 88.3+/-4.1 per cent (means+/-SD) at 140 mmol/l of sodium concentration, 68.2+/-6.9 at 180, 57.6+/-10.1 at 220, and 48.6+/-8.6 at 260 mmol/l. The G-CSF group showed 88.2+/-7.0 at 140, 79.9+/-9.4 at 180, 71.4+/-7.4 at 220, and 56.5+/-14.1 at 260 mmol/l. At 180 and 220 mmol/l significant differences were recognized. Results of this study suggest a favourable effect of G-CSF on suppressed neutrophils under the hypernatremic conditions.

Flow Cytometry↗

PubMed1998

Apoptosis of hair follicle cells in the second-degree burn wound unders hypernatremic conditions.

Progressive burn wound necrosis is an important factor as a cause of delayed healing during clinical therapy of burns. Among the causes of progressive necrosis have been attributed an insufficient blood supply or a dehydration at the zone of stasis just beneath the zone of coagulation. In a previous study evidence was presented that hypernatremia, an osmotic injury, may act to promote progressive tissue or cell death of the superficial dermal wound resulting from a heat injury. To test this hypothesis pathological features of cell death in the second-degree burn wound in the rat with hypernatremia were investigated and evidence for apoptosis in hair follicle cells was observed. Rats in the hypernatremic group were administered 10 ml of hypertonic sodium solution (850 meq 1(-1)) and the control rats were treated with 10 ml of hyponatremic solution (100 meq 1(-1)) to prevent hypernatremia. After 24 h postburn the average incidence of hair follicles (ratio to the normal skin) in the hypernatremic group was 30.1 +/-11.6 per cent and significantly lower when compared with the control group (87.6+/-6.0 per cent). The numbers of hair follicles were studied by haematoxylin and eosin stain, and the apoptotic process was investigated by an immunochemical assay and electron microscopy.

Animals↗

PubMed1998

Discovery and structure--activity relationship studies of a novel and specific peptide motif, Pro-X-X-X-Asp-X, as a platelet fibrinogen receptor antagonist.

A novel hexapeptide, H-Pro-Ser-Nva-Gly-Asp-Trp-OH 6, a specific antagonist of platelet fibrinogen receptor (GpIIb/IIIa), was discovered in a structure-activity relationship (SAR) study where the role of the N-terminal Pro moiety of an RGD-containing peptide, H-Pro-Ser-Arg-Gly-Asp-Trp-OH 1, which is a potent but not specific antagonist toward GpIIb/IIIa integrin, was investigated. This novel peptide 6 exhibits very high activity as a human platelet aggregation inhibitor (IC50 0.59 microM, human PRP/collagen) as well as marked specificity for GpIIb/IIIa. A series of substitutions at the third position (Nva residue) in this hexapeptide, focused on the conformational rigidity, led to compounds which are superior to the original novel peptide 6 with regard to anti-platelet activity. The peptides, H-Pro-Ser-Hyp-Gly-Asp-Trp-OH 17 and H-Pro-Ser-delta Pro-Gly-Asp-Trp-OH 18 with the 5-membered ring structure, which restricted the conformation of the peptide backbone at the third position, inhibited the aggregation of human platelets at submicromolar concentrations (IC50 0.39 and 0.30 microM, respectively). Further structure-activity relationship studies at each position of the peptide sequence suggest a novel motif sequence, Pro-X1-X2-X3-Asp-X4, for specific GpIIb/IIIa integrin recognition, in which the N-terminal free Pro residue and the Asp residue at the fifth position are essential to the activity. This motif sequence is summarized as follows: (1) a small amino acid such as Ser, Ala or Gly is preferable at X1 position; (2) X2 may be any amino acid, preferably a bulky amino acid such as Tle or a cyclic amino acid such as Pro; (3) X3 must be a small amino acid such as Gly; and (4) X4 is preferably an amino acid with an aromatic side chain.

Amino Acid Sequence↗

PubMed1998

Autocrine effects of transforming growth factor-alpha on the development of preimplantation mouse embryos.

PURPOSE: We wished to explore the role of transforming growth factor (TGF)-alpha in mouse embryonic development. METHODS: We examined the gene expression of TGF-alpha and epidermal growth factor receptor (EGFR) in mouse blastocysts by the reverse transcription-polymerase chain reaction and evaluated the effects of TGF-alpha on the development of preimplantation mouse embryos using TGF-alpha antisense oligodeoxynucleotide. Mouse teratocarcinoma F9 cells were also a subject of this study. RESULTS: Gene transcripts of TGF-alpha and EGFR were present in both blastocysts and F9 cells. TGF-alpha significantly stimulated the rate of blastocoel expansion in early-cavitating blastocysts and the proliferation of F9 cells. Northern blot analysis showed that TGF-alpha gene expression in F9 cells was markedly suppressed in the presence of TGF-alpha antisense oligodeoxynucleotide. TGF-alpha antisense oligonucleotide significantly reduced the rate of blastocoel expansion and the growth of F9 cells. The inhibitory effects of TGF-alpha antisense oligonucleotide on blastocysts and F9 cells were reversed by the addition of TGF-alpha. CONCLUSIONS: The present observations suggest that TGF-alpha acts as an autocrine factor in the development of preimplantation mouse embryos.

Animals↗

PubMed1998

Predictive value of vascular endothelial growth factor (VEGF) in metastasis and prognosis of human colorectal cancer.

Vascular endothelial growth factor (VEGF) may affect the phenotype of cancer cells, such as growth velocity and metastatic potential, due to its probable multifunctional property including a mitogenic activity for vascular endothelial cells. The present study was designed to investigate the association of VEGF mRNA expression with progression and metastasis of human colorectal cancer. The level of VEGF mRNA expression was quantified by Northern blot hybridization in tumorous and non-tumorous tissues obtained from 60 primary colorectal cancer patients. The ratio of the former to the latter was defined as the VEGF T/N ratio, and the prognostic significance of this ratio, following surgery, in addition to the relationship to progression and metastatic potential, was evaluated. The value of the VEGF T/N ratio was significantly correlated with the depth of tumour infiltration (P=0.046), the incidence of liver metastasis (P < 0.0001) and lymph node metastasis (P=0.036). Patient prognosis was estimated by the Kaplan-Meier method and the log-rank test. When the VEGF T/N ratio was higher than 4.8 for which the chi2 value of the log-rank test was maximal, the tumour was defined as showing overexpression of VEGF mRNA. Patients with overexpression of VEGF mRNA demonstrated poorer survival than patients without overexpression of VEGF mRNA (P < 0.001). The overall estimated hazard ratio for death in patients with overexpression of VEGF mRNA was 1.94 according to a multivariate analysis (P=0.005). Thus, VEGF is associated with the progression, invasion and metastasis of colorectal cancer, and overexpression of VEGF mRNA in the primary tumour is assumed to be closely correlated with poor prognosis in colorectal cancer patients. Moreover, the VEGF T/N ratio may be used as an independent prognostic marker in colorectal cancer patients.

Adult↗

PubMed1998

Pharmacological detection of AMPA receptor heterogeneity by use of two allosteric potentiators in rat hippocampal cultures.

1. In order to examine whether a recently developed allosteric potentiator for AMPA receptors, 4-[2-(phenylsulphonylamino)ethylthio]-2,6-difluoro-phenoxyaceta mide (PEPA), can be utilized as an indicator of AMPA receptor heterogeneity, the action of PEPA upon the increase of intracellular free calcium ion concentration ([Ca2+]i) elicited by AMPA was investigated in rat hippocampal cultures, and the action was compared with that of cyclothiazide, a well characterized allosteric modulator of AMPA receptors. 2. PEPA dose-dependently potentiated AMPA-induced increase of [Ca2+]i. In 90% (72 out of 80) of the cells in which cyclothiazide acts, PEPA potentiated the increased [Ca2+]i induced by AMPA with pronounced cell-to-cell variation in rat hippocampal cultures. 3. The ratio of the potentiation by PEPA to the potentiation by cyclothiazide (P/C ratio) also varied with cells between 0 and 2.15. It was found that the cultured hippocampal cells consisted of multiple populations with different P/C ratios. Among them two populations exhibited characteristic P/C ratios; low (0 to 0.15; 27 out of 80 cells, 34%) and high (> or = 2.00; 1 out of 80 cells, 1%) P/C ratios. The P/C ratios of the other populations were between 0.25 and 1.20, and these cells constituted 65% (52 out of 80 cells) of the cells tested. 4. Reverse transcriptase-polymerase chain reaction analysis suggested that GluR2-flip, GluR1-flip, GluR2-flop, and GluR1-flop were abundantly expressed (in this rank order) in the cultures used. 5. In Xenopus oocytes expressing GluR1, GluR3, or these subunits plus GluR2, the potentiation of AMPA response by PEPA and by cyclothiazide varied with subunit and splice-variant combinations, and the P/C ratio was between 0.19 and 2.20. Oocytes with low P/C ratios (0.19 to 0.50) and low sensitivity to PEPA potentiation (1.9 fold to 6.41 fold) were those expressing flip variants predominantly, and oocytes with high P/C ratios (1.8 to 2.2) were those expressing flop variants predominantly. Oocytes with intermediate P/C ratios (0.51 to 1.20) were those expressing various combinations of flip and flop variants, and it was impossible to specify the relative abundance of flip and flop variants in these cells. Therefore, the P/C ratio can be used to infer subunit/splice variant expression only when the ratio is low or high. 6. These results suggest that the potentiation by PEPA alone reveals cell-to-cell heterogeneity of AMPA receptors, but a comparison of the actions of PEPA and cyclothiazide further facilitates the detection of the heterogeneity.

Allosteric Regulation↗

PubMed1998

Expression of endothelial and inducible nitric oxide synthase in human glomerulonephritis.

The presence of nitric oxide (NO) in the kidney has been implicated in the pathogenesis of human glomerulonephritis. However, the exact type of glomerular cells that express NO synthase (NOS) and the NOS isoform involved in the local production of NO has not been identified in the human diseased kidney. We examined the expression of three isoforms of NOS, inducible NOS (iNOS), endothelial NOS (eNOS) and brain NOS (bNOS) in the renal tissue of patients with IgA nephropathy (IgAN, N = 10), lupus nephritis (LN, N = 5), membranous nephropathy (MN, N = 5) and minimal change nephrotic syndrome (MCNS, N = 5). Sections were immunostained and the correlation between the expression of each NOS and the degree of glomerular injury in that section was also examined. Normal portions of surgically resected kidneys served as controls. eNOS was present in glomerular endothelial cells and endothelium of cortical vessels in the control and diseased kidneys. iNOS was localized in mesangial cells, glomerular epithelial cells and infiltrating cells in the diseased glomeruli, whereas immunostaining for iNOS was hardly detected in control kidneys. In addition, the expression pattern of eNOS in each glomerulus was the reverse of that of iNOS. In IgAN and LN, the extent of staining for eNOS correlated negatively with the degree of glomerular injury, while the extent of staining for iNOS correlated positively with the degree of glomerular injury in the same tissues. bNOS was not detected in normal or nephritic glomeruli. Our results indicate the presence of a NO pathway in human diseased kidney, and suggest that NO derived from eNOS and iNOS may be involved in the progression of renal diseases and that NO derived from each NOS may play an important role in different way in human inflamed glomeruli.

Adult↗

PubMed1998

Expression of decay accelerating factor mRNA and complement C3 mRNA in human diseased kidney.

BACKGROUND: Decay accelerating factor (DAF), a product of mesangial cells in vitro, is expressed on the surface of cells and is a candidate for the focal suppression of complement activation. It is not clear at present whether the levels of expression of DAF and intrarenal C3 synthesis correlate with the level of tissue injury. METHODS: Immunohistochemistry for DAF and C3 and nonradioactive in situ hybridization with digoxigenin-labeled oligonucleotide probe for DAF and C3 mRNA were performed in 22 tissue samples of kidneys from patients with IgA nephropathy (IgAN), 6 with membranous nephropathy (MN), 6 with lupus nephritis (LN), and five normal kidneys. RESULTS: In the normal kidney, DAF was confined to the juxtaglomerular apparatus and little or no C3 was detected; however, a few glomerular cells were positive for DAF mRNA but no C3 mRNA positive cells were detected. In diseased kidneys, DAF and C3 as well as their mRNAs were detected in mesangial cells, tubular cells and infiltrating cells. Glomerular epithelial cells and Bowman's capsule cells contained little or no DAF and C3 but were positive for their mRNAs. The mean percentages of mesangial cells positive for DAF and C3 mRNAs were 49.3 +/- 11.5% and 50.7 +/- 10.3% in IgAN, and 17.0 +/- 6.3% and 19.4 +/- 9.0% in MN, respectively. The percentage of mesangial cells positive for DAF and C3 mRNAs among intraglomerular cells correlated positively with the degree of mesangial proliferation and glomerular sclerosis in IgAN. In contrast, in LN the percentage of glomerular cells positive for DAF mRNA correlated negatively with the degree of glomerular injury, while the percentage of cells positive for C3 mRNA did not change with the progression of the disease. The ratio of C3 mRNA/DAF mRNA of glomerular cells correlated with the degree of glomerular injury in both IgAN and LN. In the tubulointerstitium, the percentage of cells expressing mRNA, and C3 mRNA/DAF mRNA radio correlated with the degree of tubular atrophy and interstitial broadening in both IgAN and LN. CONCLUSIONS: We conclude that DAF and C3 mRNAs are synthesized in human diseased kidneys, and that a balance between locally synthesized DAF and C3 may be important in the progression of glomerulonephritis.

Adult↗

PubMed1998

Expression of VLA-4 on peripheral mononuclear cells in patients on chronic haemodialysis with carpal tunnel syndrome.

BACKGROUND: Carpal tunnel syndrome (CTS) is a major complication in long-term haemodialysis patients and is thought to be a form of haemodialysis-associated amyloidosis. CTS may be due to the deposition of amyloid as well as local inflammatory process in the carpal tunnel. Although macrophage-like cells infiltrating the tenosynovium of carpal tunnel are known to express mRNA for adhesion molecules, the level of expression of adhesion molecules on peripheral blood mononuclear cells (PBMC) in patients with CTS is unknown. METHODS: We compared the expression of very late activation antigen (VLA-4) on PBMC by flow cytometry in 14 patients on haemodialysis (6-21 years) with CTS, nine on haemodialysis (1-6 years) but without CTS and six patients on chronic ambulatory peritoneal dialysis (CAPD, 1-5 years) without CTS. RESULTS: The expression of VLA-4 on peripheral lymphocytes was not different among the groups. However, the FACScan fluorescence histogram of VLA-4 expression on peripheral monocytes showed a bimodal pattern in the CTS group, and the rate of the high intensity portion of the expressed VLA-4 on monocytes was significantly higher in CTS than other groups (P<0.05). The observed differences were not based on differences in the type of the dialysis membrane. We also examined the adhesion of PBMC to fibronectin-coated plates. The number of adherent PBMC was significantly higher in patients with CTS than in other groups (P<0.05). CONCLUSION: Our results suggest that increased expression of VLA-4 on peripheral monocytes and augmented adhesion capacity of PBMC to fibronectin may be involved in the development of CTS in haemodialysis patients.

Carpal Tunnel Syndrome↗

PubMed1998

Quantitative cytology of nasal secretions with perennial allergic rhinitis in children: comparison of noninfected and infected conditions.

This study was performed to quantify the number of inflammatory cells in nasal secretions from pediatric patients with perennial allergic rhinitis under noninfected and infected conditions. Nasal secretions were obtained from seven children under both noninfected and infected conditions with perennial allergic rhinitis to house dust mites, and secondary quantitative cytology was performed on the secretions. The number of neutrophils under infected condition was significantly higher than that under noninfected condition (P < .05), whereas the number of eosinophils in infected condition was significantly lower than that in noninfected condition (P < .05). The ratio of eosinophil count to neutrophil count was more than 0.1 in noninfected condition. The ratio was significantly decreased in infected condition (P < .02). These results suggest that the distribution of inflammatory cells in the nasal mucus of children with allergic rhinitis would be modified under infected condition.

Adolescent↗

PubMed1998

Atypical form of the fourth criterion for transient entrainment.

The typical fourth criterion for transient entrainment is defined when both a sudden shortening in conduction interval to and a distinct change in electrogram morphology at a bipolar recording site are demonstrated while performing overdrive pacing of a reentrant tachycardia from a single pacing site at two different constant rates. The purpose of this article was to test the hypothesis that if an intracardiac recording site showing both orthodromic and antidromic capture with entrainment pacing is located suitably distant from the circuit, sudden shortening in conduction interval to that site may occur without any significant change in the bipolar electrogram morphology (i.e., atypical form of the fourth criterion). Atrial overdrive pacing of orthodromic tachycardia was performed in 20 patients with either left anterior (12 patients) or left posterior (8 patients) accessory pathways. We investigated the effects of overdrive pacing from the proximal or distal coronary sinus, specifically effects on the electrogram interval and the electrogram morphology at the right atrial appendage. Overdrive pacing of orthodromic tachycardia from the proximal coronary sinus was performed in 10 of the 12 patients with left anterior accessory pathways; those 10 patients demonstrated the first entrainment criterion at the right atrial appendage site. Overdrive pacing of orthodromic tachycardia at still shorter cycle lengths demonstrated a sudden shortening in conduction interval to the right atrial appendage site. Despite shortening in conduction interval the morphology of the right atrial appendage electrogram was completely or almost identical to that during orthodromic tachycardia, indicating an atypical form of the fourth criterion. This criterion was not demonstrated in patients with left posterior accessory pathways. Thus, atypical fourth entrainment criterion was demonstrated during overdrive pacing of orthodromic tachycardia from the proximal coronary sinus only in patients with left anterior accessory pathways. Demonstration of atypical fourth criterion seems largely dependent on the location of the accessory pathway, the pacing, and the recording sites.

Adolescent↗

PubMed1998

Catheter ablation of ventricular tachycardia in patients with right ventricular dysplasia: Identification of target sites by entrainment mapping techniques.

OBJECTIVE: To identify target sites for radiofrequency ablation of ventricular tachycardia (VT) by entrainment mapping techniques in patients with arrhythmogenic right ventricular dysplasia. METHODS: Entrainment mapping and radiofrequency ablation of eight VTs was performed in seven patients. Radiofrequency ablation was applied at 31 reentry circuits sites that were classified based on findings during entrainment. RESULTS: By entrainment criteria the 31 sites were classified as: exit sites (n = 12), proximal sites (n = 6), and outer loop sites (n = 13). Radiofrequency current application terminated VT at 7 of 31 sites: 2 of 12 exit sites (17%), 4 of 6 proximal sites (67%), and 1 of 13 outer loop sites (8%). CONCLUSION: Radiofrequency ablation terminated VTs most often at sites proximal to the exit as opposed to outer loop sites and exit sites (P = 0.05). The critical isthmus for ablation of VT in right ventricular dysplasia often may be distant to the exit.

Arrhythmogenic Right Ventricular Dysplasia↗

PubMed1998

S-100 protein-positive dendritic cells in follicular lesions of the thyroid.

Little is known about the role of S-100 protein-positive dendritic cells in follicular lesions of the thyroid. In 36 cases of adenomatous goitre, 18 cases of follicular adenoma, and 7 cases of follicular carcinoma, we investigated the incidence and distribution of S-100 protein-positive dendritic cells using immunohistochemical staining. Four cases (10.5%) of adenomatous goitre, five cases (31.3%) of follicular adenoma, and 6 cases (85.7%) of follicular carcinoma contained S-100 protein-positive dendritic cells in the subcapsular area and/or the hyalinized stroma. Dendritic cells in the subcapsular area were observed only in lesions with thick capsules and not those with thin capsules. In most cases of follicular carcinoma, + + to + + + of the dendritic cells was seen together with a few lymphocytes and fibroblasts in the subcapsular areas. In contrast, cases of adenomatous goitre and follicular adenoma showed only a few dendritic cells without any inflammatory cells. Dendritic cells in follicular thyroid lesions may play some role in capsular formation or may be a secondary phenomenon due to capsular formation.

Adenocarcinoma, Follicular↗

PubMed1998

Therapeutic apheresis for renal diseases.

Plasma exchange is used frequently in renal diseases for the removal of the humoral components of immune responses. Various pathological circulating factors are recognized in primary and secondary renal diseases. Recent advances in medical technology have allowed a wider clinical application of plasmapheresis in the clinical management of a variety of conditions. However, the clinical efficacy of plasmapheresis in renal diseases is still controversial. In this article, we review the therapeutic use of apheresis in different renal diseases.

Anti-Glomerular Basement Membrane Disease↗

PubMed1998

Downward gaze palsy caused by bilateral lesions of the rostral mesencephalon.

A 55-year-old man with diabetes mellitus developed diplopia and experienced difficulty in moving his eyes in the vertical plane, especially downward. Horizontal movement of each eye was normal with exotropia. Magnetic resonance imaging revealed small and high signals on both sides of the midbrain near the interstitial nucleus of Cajal (INC). Based upon the recent experimental evidence, we speculate that bilateral lesions involving the INC may have caused downward gaze palsy in our patient.

Blepharoptosis↗

PubMed1998

Anti-CD8 monoclonal antibody protects against spontaneous IgA nephropathy in ddY mice.

We investigated the effects of anti-CD4 monoclonal antibody (mAb) and/or anti-CD8 mAb in ddY mice, an animal model of spontaneous IgA nephropathy. Female ddY mice were treated with 18 intravenous injections of anti-CD4 and/or anti-CD8 mAb at 2-week intervals. This was based on our observation that a single injection of anti-CD4 mAb or anti-CD8 mAb caused a selective depletion in CD4+ T cells for 2 weeks and CD8+ T cells for 4 weeks, respectively. The level of proteinuria, serum IgA, and changes in the histopathological features of renal tissue samples were assessed in treated mice between the age of 4 and 40 weeks. The level of proteinuria increased with age, but there was not significant difference among the groups. No animal developed microhematuria throughout the study. Treatment with anti-CD4 mAb produced a mild to moderate level of mesangial hypertrophy at 20 and 40 weeks, similar to the results in untreated mice. The lowest degree of mesangial hypertrophy occurred in mice treated with anti-CD8 mAb up to the age of 40 weeks. Treatment with a combination of anti-CD4 and anti-CD8 mAbs produced effects that were similar to those observed on treatment with anti-CD8 mAb alone. Our results suggest that CD8+ T cells mediate mesangial proliferation and the progression of nephropathy in ddY mice.

Animals↗

PubMed1998

Coexpression of collagens and collagen-binding heat shock protein 47 in human diabetic nephropathy and IgA nephropathy.

The mechanism of structural changes of the kidney in human diabetic nephropathy (DN) and IgA nephropathy (IgAN) is not yet completely known, but excessive deposition of extracellular matrix (ECM), including various collagens, may be crucial to this process. Heat shock protein (HSP) 47 has been identified as collagen-binding stress protein, shown to have a specific role in the intracellular processing of procollagen molecules during collagen assembly. To determine whether increased deposition of collagens in human DN and IgAN is related to HSP47, we investigated the expression of HSP47 in renal biopsy and autopsy sections obtained from 22 DN and 45 IgAN patients. Five renal biopsy specimens, diagnosed as minor glomerular abnormalities, were simultaneously studied as controls. Monoclonal antibodies specific for HSP47, type III collagen and type IV collagen were used to assess the relative expression of their proteins in paraffin-embedded renal sections by immunohistochemistry. Increased deposition of collagens was closely related to the sclerotic activity of the disease process in DN and IgAN; increased deposition of collagens was often present in relation to a strong expression of HSP47, a stress protein known to regulate collagen synthesis/assembly. By double immunostaining, we found colocalization of collagens and their molecular chaperone HSP47 in the sclerotic glomeruli and tubulointerstitium in DN and IgAN. Our results strongly support a pathologic role for HSP47 in both these diseases and that increased levels of HSP47 may play an important role in the excessive assembly of collagens resulting in glomerulosclerosis and interstitial fibrosis found in DN and IgAN patients.

Actins↗

PubMed1998

Expression of c-kit messenger ribonucleic acid in human oocyte and presence of soluble c-kit in follicular fluid.

The c-kit protooncogene receptor and its ligand stem cell factor (SCF) regulate the proliferation and survival of germ cells as well as hematopoietic cells and melanocytes. In adult rodent ovary, c-kit and SCF play important roles in follicular development. However, little information about c-kit in the human ovary is available. In this study, we examined the expressions of c-kit messenger ribonucleic acid (mRNA) and c-kit protein in human oocytes, granulosa cells, and follicular fluid obtained from the women who underwent in vitro fertilization or laparoscopic examination. Expression of c-kit mRNA was detected by RT-PCR in the oocytes and granulosa cells. Western blot analysis showed the presence of soluble c-kit protein in the follicular fluid, and lower levels of c-kit protein were detected in the granulosa cells and the supernatant of granulosa cell cultures. The concentration of soluble c-kit in follicular fluid measured by enzyme-linked immunosorbent assay showed significant correlation with fluid volume and follicular fluid concentrations of estradiol, testosterone, and androstenedione. In summary, we found for the first time the presence of c-kit mRNA and soluble c-kit protein in human oocytes and follicular fluid. The results suggested that in human ovary, c-kit may play an important role in follicular development.

Adult↗