Biomedical subjects

H Kanayama

Publications and source records attributed to H Kanayama.

At least 37 records · Page 2Linked to original sources

PubMed1999

A case of complete testicular feminization: laparoscopic orchiectomy and analysis of androgen receptor gene mutation.

BACKGROUND: Analysis of an androgen receptor gene mutation and a bilateral laparoscopic orchiectomy were performed on a 19-year-old patient diagnosed as a case of complete testicular feminization. METHODS: DNA sequencing of an androgen receptor gene mutation and laparoscopic orchiectomy were performed. RESULTS: A novel point mutation substituting a proline residue (CCG) for a leucine residue (CTG) was observed in codon 892 of exon 8 in the hormone-binding domain of the androgen receptor gene. Bilateral intra-abdominal testes were resected uneventfully by means of laparoscopic orchiectomy. CONCLUSION: We conclude that genetic analysis of androgen receptor gene mutation is essential for diagnosis of teon and laparoscopic orchiectomy is a useful therapeutic alteration as a minimally invasive treatment.

Adult↗

PubMed1999

A case of renal metanephric adenoma: histologic, immunohistochemical and cytogenetic analyses.

BACKGROUND: A unique case of metanephric adenoma of the left kidney is reported in a 61-year-old woman presenting with an incidental renal mass on ultrasonography. METHODS/RESULTS: On radiographic examination, the presence of hypovascular renal cell carcinoma was suspected and left radical nephrectomy was performed. The resected tumor, measuring 4.9 x 4.7 x 4.5 cm, was well-circumscribed and solid and its cut surface was tan-pink with foci of focal hemorrhage and cystic change. Microscopically, the tumor was composed of uniformly small acini with hyperchromatic round nuclei. Some acini were dilated and occasionally contained glomeruloid-like bodies and psamoma bodies. Immunohistochemically, tumor cells showed positive immunoreaction for vimentin, cytokeratin and Leu 7. Cytogenetically, the tumor did not show numerical aberrations of chromosome 7 or 17 by fluorescence in situ hybridization. CONCLUSIONS: The patient is alive without recurrence or metastasis 4 years after surgery. Metanephric adenoma must be differentiated from other renal tumors, particularly Wilms' tumor or low-grade renal cell carcinoma. Immunohistochemical and cytogenetic analysis may be helpful in difficult cases.

Adenoma↗

PubMed1999

MN/CA9 gene expression as a potential biomarker in renal cell carcinoma.

OBJECTIVE: To compare the levels of MN/CA9 expression with clinicopathological variables in renal cell carcinoma (RCC), and thus evaluate MN/CA9 expression as a possible biomarker for RCC. MATERIALS AND METHODS: The level of expression of MN/CA9 was evaluated in 76 surgically obtained tissue samples (49 from RCC, 22 from normal kidney and five from oncocytoma) using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis. In RCC, MN/CA9 expression was compared with stage, grade and cell type. RESULTS: MN/CA9 was expressed in 42 of 49 (86%) RCC samples, but in only two of 22 (9%) normal kidney and none of five oncocytoma samples. Levels of MN/CA9 expression were significantly higher in tumours consisting only of clear cells than in those containing other cell types (P=0.0189), and MN/CA9 was expressed in 34 of 37 (92%) RCC samples consisting only of clear cells. Tumours of low clinical stage showed a striking increase in MN/CA9 expression, and high MN/CA9 expression was associated with a good patient outcome. CONCLUSION: These results suggest that MN/CA9 expression is a potential diagnostic biomarker of RCC, especially the clear-cell type, and can be targeted using molecular biological techniques.

Adult↗

PubMed1999

[A case of renal oncocytoma with cystic formation].

A 60-year-old man was admitted to our hospital because of a right renal mass incidentally detected by ultrasonography during a general health check. Computerized tomography (CT) and magnetic resonance imaging (MRI) revealed a solid mass measuring 6 cm diameter containing a cystic portion in the right kidney. Cystic renal cell carcinoma was suspected, and right nephrectomy was performed. The gross appearance showed a well circumscribed mahogany brown tumor in the lower portion. On cross section of the tumor, a solid mass was seen in the cystic portion. Microscopically, oncocytic cells with eosinophilic granular cytoplasm were scattered on the cystic wall, and tumor cells formed microcystic structures in the solid part. Therefore, the tumor was diagnosed as renal oncocytoma with cystic formation. Only twelve cases have previously been reported in the literature.

Adenoma, Oxyphilic↗

PubMed1999

[Clinical statistics of stage I testicular tumor].

PURPOSE: A survey of stage I testicular tumors in the Chugoku-Shikoku district was taken in order to explore the clinical characteristics. PATIENTS AND METHODS: Three hundred and forty eight cases of stage I testicular tumor treated at 46 facilities in the Chugoku-Shikoku district between 1984 and 1992 were collected. Subjects' background factors, treatment methods and prognosis were studied. RESULTS: Tissue types were 249 (71.6%) seminoma and 99 (28.4%) non-seminoma. Adjuvant therapy for seminoma cases included 138 post-operative radiotherapy (4 recurrences, 3 cancer deaths), 57 chemotherapy (no recurrences, 2 contralateral testis tumor cases) and 48 were under surveillance (no recurrence). Adjuvant therapy for non-seminoma cases included 47 chemotherapy (1 recurrence) and retroperitoneal lymph node dissection was performed on 6 cases. Forty cases were under surveillance (1 recurrence). Of 8 (2.3%) cases with recurrence, 6 showed onset within two years and 2 after two years. Four of the 8 cases with recurrence were seminoma (1.1% of seminoma cases) and the other 4 were non-seminoma (4.0% of non-seminoma cases). All 3 (0.9% of all cases) of the cancer death cases were seminoma that received post-operative radiotherapy, while there were no cancer deaths in non-seminoma cases. CONCLUSION: Prognosis of stage I testicular tumor is good. Although the recurrence rate was higher in non-seminoma cases, cancer deaths were only observed in seminoma cases.

Adolescent↗

PubMed1999

[Extravasation into a renal sinus cyst due to ureteral calculus: a case report].

A 71-year-old man who had been treated conservatively for advanced prostate cancer with hormonal therapy presented with complaint of left flank pain. Intravenous urography demonstrated obstruction caused by a left upper ureteral calculus and leakage of contrast medium outside the renal pelvis and calyces. Left percutaneous nephrostomy was performed, and subsequent nephrostography showed extravasation into a parapelvic renal sinus cyst previously recognized on follow-up computed tomography (CT). The left ureteral calculus was treated with extracorporeal shock wave lithotripsy (ESWL), after which obstruction and extravasation disappeared. One month later, abdominal CT demonstrated no left renal nor ureteral calculi, as well as a reduction in the left renal sinus cyst. Urinary extravasation sometimes occurs as a complication of acute urinary obstruction. However, extravasation into a cyst is very rare. We have found only one case reported in the literature, so far.

Aged↗

PubMed1999

[The so-called megaureter-megacystis syndrome: a case report].

We encountered a patient with megaureter-megacystis syndrome showing a giant bladder and dilated ureters with marked reflux, which is very rare; to our knowledge, only 2 patients have been reported in Japan. The patient was a 4-year-old boy, who showed inborn polyposia and polyuria, and proteinuria at the age of 1 year. He visited the pediatric department in our hospital complaining of cold-like symptoms, stomachache and diarrhea. Urinary infection and kidney dysfunction were observed, and the patient was hospitalized for close examination. Bilateral pyelocaliceal hydronephrosis was detected by ultrasonography, and the patient was referred to our department. CT revealed bilateral hydronephrosis (right atrophic kidney), hydroureters and megacystis. Bilateral grade V vesicoureteral reflux, an increase in the bladder volume (> 300 ml), and urination without residual urine were noted by voiding cystourethrography. Uroflowmetry revealed that maximum flow rate was 21.6 ml/sec, voided volume was 110 ml, and residual volume was 24 ml. From these examinations, the patient was diagnosed as having megaureter-megacystis syndrome, and underwent antireflux operation of the bilateral ureters using Cohen's procedures.

Child, Preschool↗

PubMed1999

[Postoperative prophylactic intravesical instillation of tetrahydropyranyl-adriamycin (THP) for superficial bladder cancer].

Intravesical instillation of tetrahydropyranyl-adriamycin (THP) was performed on 51 patients with superficial bladder cancer after transurethral resection (TUR) for prophylaxis of recurrence. The instillation was carried out with 20 mg of THP dissolved in 40 ml of distilled normal saline. Instillation was performed once 24 hours postoperatively, 9 times every 2 weeks, and 8 times every 4 weeks. These drugs were instilled for 30 to 60 minutes. The recurrence-free survival at 1, 2 and 3 years was 74.5%, 64.6% and 58.0%, respectively. Side effects of THP instillation were observed in only 4 cases (7.8%) as slight urinary frequency or micturition pain. Cases involving 5 or more tumors, or tumors measuring 3 cm or larger, more frequently demonstrated recurrence. The cases that did not respond to preoperative intravesical instillation of THP demonstrated a high frequency of recurrence. Intravesical instillation of THP as a prophylaxis against recurrence of superficial bladder cancer was effective in selected patients.

Administration, Intravesical↗

PubMed1999

Biologic markers in prostatic intraepithelial neoplasia: immunohistochemical and cytogenetic analyses.

OBJECTIVE: We evaluated the biological properties of High-grade prostatic intraepithelial neoplasia (PIN) by immunohistochemistry and fluorescence in situ hybridization (FISH) analysis in relation to normal tissue and carcinoma lesions. MATERIALS AND METHODS: Immunohistochemical staining and FISH were performed on 23 formalin-fixed radical prostatectomy specimens taken from patients with PIN. Assays were performed using MIB-1, chromogranin A (CGA) and an anti-androgen receptor antibody (AR). A centromere probe for chromosome 8 was used to test for aneuploidy. RESULTS: The MIB-1 index of cancerous specimens (16.2 +/- 10.5%) was significantly higher than that of benign (1.9 +/- 1.6%, p < 0.0001) or PIN (4.0 +/- 4.5%, p < 0.0001) specimens. The percentage of CGA positive cells was significantly lower in normal tissue (1.2 +/- 1.8%) than in PIN (3.5 +/- 2.9%, p = 0.012) or carcinoma (5.4 +/- 4.9%, p = 0.005) lesions. Positive staining for AR was consistently observed in the nuclei of both benign and malignant epithelial cells, but positive cytoplasmic staining was also seen in PIN epithelial cells. No significant difference in FISH detected anomalies were found between PIN and carcinoma specimens. CONCLUSIONS: Our studies concerning proliferative activity, NE differentiation and chromosomal anomalies of prostatic specimens support the hypothesis that PIN is a biologically intermediate stage in the pathogenesis of prostatic carcinoma. The cellular distribution of AR was altered in PIN cells, but the role of AR in PIN is not yet clear.

Aged↗

PubMed1999

Prevention of the initial testosterone surge induced by a luteinizing hormone-releasing hormone analogue in prostate cancer patients: the endocrinological effects of pretreatment with chlormadinone acetate.

We investigated the endocrinological effects of pretreatment with chlormadinone acetate (CMA) in preventing the initial testosterone surge induced by a luteinizing hormone-releasing hormone (LH-RH) analogue. A total of 25 patients with previously untreated prostate cancer were included in this study. The patients were randomly assigned to 2 treatment groups: Group 1; CMA therapy was begun 4 weeks before the initial LH-RH analogue injection. Group 2; CMA therapy was begun 2 weeks before the initial LH-RH analogue injection. After the initial LH-RH analogue injection, CMA was administered during this study. After LH-RH analogue application, the mean values of serum luteinizing hormone (LH) and testosterone increased in both groups on day 3. However, LH and testosterone levels remained beneath pretreatment values in both groups. The mean relative PSA levels did not significantly increased on day 3 and day 7 in both groups. Our results indicate that pretreatment with CMA for 2 weeks was sufficient to prevent the initial testosterone surge in the maximal androgen blockade which was associated with CMA.

Administration, Oral↗

PubMed1999

[Serum alkaline phosphatase flare in prostate cancer accompanied by bone metastases and treated with hormonal therapy. TEKK Study Group].

To clarify the roles of alkaline phosphatase (ALP) flare in prostate cancer accompanied by bone metastases and treated with hormonal therapy, we evaluated the clinicopathological character, treatment efficacy and outcome for patients with and without ALP flare. We evaluated 60 patients with newly diagnosed prostate cancer accompanied by bone metastases and treated with hormonal therapy, whose response in terms of serum prostate specific antigen (PSA) levels showed a partial response (PR) or better response. The patients were classified into two groups, an ALP flare group (13 cases) and a non-ALP flare group (47 cases). The former showed serum ALP elevation of more than double, and the latter less than double that of pretreatment levels following hormonal therapy. Patient characteristics, PSA response and outcome were compared between the two groups. Extent of disease (EOD) as grade of bone metastasis was significantly higher in the ALP flare group than in the non-flare group (p = 0.0352). Pre-treatment serum PSA levels were also significantly higher in the ALP flare group (p = 0.0010). However, there were no significant differences in pretreatment serum ALP levels. Serum PSA levels were normalized in 37 of the 47 patients (78.7%) in the non-ALP flare group compared with 6 of the 13 (46.2%) in the ALP flare group (p = 0.0211). Moreover, the period until biochemical failure was significantly shorter for the ALP flare than the non-flare group (p = 0.0027). These results suggest that prostate cancer patients with bone metastases in whom ALP flare is observed in response to hormonal therapy tend to have more extensive bone metastases, high pretreatment PSA levels, to be resistant to PSA normalization and more likely to experience biochemical failure.

Aged↗

PubMed1998

Enhanced secretion of insulin plays a role in the development of atherosclerosis and restenosis of coronary arteries: elective percutaneous transluminal coronary angioplasty in patients with effort angina.

OBJECTIVES: We investigated the relation between insulin and coronary atherosclerosis and restenosis of the coronary arteries, by performing elective percutaneous transluminal coronary angioplasty (PTCA). BACKGROUND: Insulin is known to promote atherosclerosis of the arteries and has been implicated in the development of restenosis after PTCA. METHODS: Of 210 angina patients who underwent PTCA, newly detected lesions in 35 consecutive nondiabetic subjects without previous intervention on the same main coronary arteries were analyzed after a 75-g oral glucose tolerance test (OGTT) and follow-up coronary angiography. Atherosclerotic lesions were evaluated by pattern, severity and extent. Restenosis was defined as loss of gain, the percentage of loss of the initial gain in the coronary diameter achieved by PTCA > or = 50%. RESULTS: Patients with restenosis had a significantly higher extent index (a marker of atherosclerosis), insulin area, ratio of insulin area to glucose area, insulinogenic index and minimal lumen diameter after PTCA than those without restenosis (p=0.001, 0.011, 0.002, 0.016 and 0.041, respectively). Simple regression analysis revealed that only the ratio of insulin area to glucose area (a relative marker of enhanced insulin secretion) significantly correlated with the extent index (p=0.035). Extent index, insulin area, the ratio of insulin area to glucose area and insulinogenic index significantly correlated with loss of gain (p=0.001, 0.010, 0.002 and 0.032, respectively). Stepwise multiple regression analyses revealed that extent index and the ratio of insulin area to glucose area significantly correlated with loss of gain. CONCLUSIONS: Enhanced secretion of insulin during the OGTT might be useful as a predictor of coronary atherosclerosis and of restenosis after elective PTCA in nondiabetic patients with effort angina.

Aged↗

PubMed1998

Prognostic values of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 expression in bladder cancer.

BACKGROUND: Matrix metalloproteinase-2 (MMP-2), which degrades the extracellular matrix or the basement membrane, has an essential role in tumor invasion and metastasis. To evaluate the roles of MMP-2, its inhibitor (tissue inhibitor of metalloproteinase-2 [TIMP-2]), and its activator (membrane-type matrix metalloproteinase-1 [MT1-MMP]) in tumor invasion or as a prognostic factor in patients with bladder carcinoma, the authors investigated the expression of MMP-2, TIMP-2, and MT1-MMP in patients with bladder carcinoma. METHODS: Tissues obtained from 41 patients with bladder carcinoma were used for analysis. Expression of MMP-2, TIMP-2, MT1-MMP, and glyceraldehyde-3-phosphate dehydrogenase was examined by reverse transcriptase-polymerase chain reaction analysis. Correlations between the levels of MMP-2, TIMP-2, and MT1-MMP expression and histologic findings or patient outcome were evaluated. RESULTS: Expression of MMP-2 and TIMP-2 was significantly higher in muscle invasive pT2< or = bladder tumors than in pT1a tumors (MMP-2: P < 0.0005; TIMP-2: P < 0.005). Moreover, high levels of MMP-2 and TIMP-2, as well as MT1-MMP expression, all were strongly associated with decreased survival (MMP-2: P < 0.0001; TIMP-2: P < 0.0001; and MT1-MMP: P < 0.005). Even within the radically cystectomized muscle invasive pT2< or = tumor group, patients with a high expression of any of these three genes had a worse prognosis than those with low expression (MMP-2: P < 0.05; TIMP-2: P < 0.05; and MT1-MMP: P = 0.0641). CONCLUSIONS: MMP-2 and TIMP-2 are believed to contribute to the invasive properties of bladder carcinoma. The authors report that expression of MMP-2, TIMP-2, and MT1-MMP are useful prognostic indicators in patients with bladder carcinoma and may be helpful in designing treatment protocols.

Aged↗

PubMed1998

Usefulness of enhanced insulin secretion during an oral glucose tolerance test as a predictor of restenosis after direct percutaneous transluminal coronary angioplasty during acute myocardial infarction in patients without diabetes mellitus.

To determine predictive factors of the development of restenosis after percutaneous transluminal coronary angioplasty (PTCA), 25 nondiabetic nonobese patients aged <80 years old and 57 consecutive patients with successful direct PTCA with acute myocardial infarction were subjected to a 75-g oral glucose tolerance test (OGTT) and underwent follow-up coronary angiography 4 months later. The relation between the development of restenosis (late loss index: the decrease in the absolute minimal lumen diameter [MLD] at follow-up coronary angiography divided by MLD measured 1 day after PTCA) and the results of OGTT together with basic patient characteristics like age, body mass index, plasma levels of cholesterol, triglycerides, and high-density lipoprotein cholesterol were analyzed. Spearman's rank correlation analysis revealed that neither age, body mass index, nor plasma lipids correlated with late loss index, but only insulin area (p = 0.041) and insulin area/glucose area (p = 0.038) significantly correlated with the development of restenosis; a stepwise multiple regression analysis revealed that the insulin area was the only independent predictor of restenosis (p = 0.019). These results suggest that enhanced insulin secretion in response to glucose plays an important role in the development of restenosis after direct PTCA in non-diabetic patients, which may be through the direct action of insulin on smooth muscle cells of the coronary artery. This study also suggests the importance of performing OGTT for patients undergoing PTCA for the prediction of the development of restenosis.

Aged↗

PubMed1998

Role of the matrix metalloproteinase and tissue inhibitors of metalloproteinase families in noninvasive and invasive tumors transplanted in mice with severe combined immunodeficiency.

OBJECTIVES: To elucidate the role of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in human urothelial cancers, we studied gene expressions of MMPs, TIMPs, and membrane-type 1 matrix metalloproteinase (MT1-MMP) in noninvasive or invasive tumor lines transplanted in mice with severe combined immunodeficiency (SCID). METHODS: The UCT-1 tumor line, derived from bladder cancer, is a noninvasive transplantable tumor with no evidence of metastasis. The UCT-2 tumor line, derived from a renal pelvic tumor, extensively invades without metastasis. We examined gene expressions of MMPs-1, 2, 3, 7, 8, 9, 10, and 11, TIMPs-1, 2, and 3, and MT1-MMP in UCT-1 and 2 by semiquantitative polymerase chain reaction analysis. RESULTS: Significantly higher gene expression of MMP-2 was detected in the invasive UCT-2 tumor line than in the noninvasive UCT-1 tumor line. Although both tumor lines expressed TIMP-1 and MT1-MMP, stronger gene expression of MT1-MMP was observed in the UCT-2 tumor line than in the UCT-1 tumor line. The other MMPs or TIMPs were not detected in either of the lines. CONCLUSIONS: MMP-2 and MT1-MMP may have an important role in the invasion mechanism of urothelial cancers.

Aged↗

PubMed1998

Immunohistochemical analysis of Ki-67 antigen and Bcl-2 protein expression in prostate cancer: effect of neoadjuvant hormonal therapy.

OBJECTIVE: To determine differences in the immunohistochemical (IHC) expression of Bcl-2 protein and Ki-67 antigen in patients with prostatic cancer who underwent radical prostatectomy with or without neoadjuvant hormonal therapy. MATERIALS AND METHODS: Ki-67 antigen and Bcl-2 protein were detected by IHC using MIB-1 and Bcl-2 antibodies in prostatectomy specimens from 28 patients who received hormonal therapy before surgery (group 1) and 51 patients who did not (group 2). RESULTS: In group 2, the mean MIB-1 index increased with increasing grade of tumour, from 11.6% in low-grade to 24.7% in high-grade tumours (P = 0.002). Bcl-2 expression did not correlate with either tumour grade or stage. In group 1, there were no correlations between Bcl-2 expression or MIB-1 index and tumour grade or stage. More tumours in group 1 were Bcl-2-positive (16 of 28, 57%) than were tumours in group 2 (11 of 51, 22%; P = 0.003). The mean (SD) MIB-1 index of tumours in group 2 [15.6 (14.4)%], was significantly greater than that of tumours in group 2 [6.8 (7.5)%; P = 0.004]. CONCLUSIONS: These results indicate that Bcl-2 positivity is increased by androgen ablation therapy and conversely, that the proliferative activity of cancer cells is significantly reduced. The expression of Bcl-2 protein may play a role in the ability of prostate cancer cells to survive in an androgen-deprived environment.

Aged↗

PubMed1998

Semi-quantitative analysis of telomerase activity in exfoliated human urothelial cells and bladder transitional cell carcinoma.

OBJECTIVE: To determine the utility of detecting telomerase activity in transitional cell bladder cancer, using the telomeric repeat amplification protocol (TRAP) assay, and thus provide a test for the detection and monitoring of bladder cancer, especially low-grade tumours. PATIENTS, SUBJECTS AND METHODS: Telomerase activity was assayed in bladder cancer tissues and the exfoliated urothelial cells from 29 patients with bladder cancer, 10 with benign disease, and in 10 healthy subjects using the TRAP assay. The levels were assessed semiquantitatively by calculating the ratio to an internal telomerase assay standard. RESULTS: Telomerase activity was very low in the exfoliated urothelial cells from all healthy subjects and patients with benign disease, with a mean (SD) ratio of 0.25 (0.03) and 0.33 (0.04), respectively. A threshold ratio of 0.4 was calculated as the mean +/- 2 SD of the telomerase activity level of the exfoliated urothelial cells from patients with benign disease. Using this threshold, telomerase activity was negative in exfoliated urothelial cells from all benign cases (100% specificity) and positive in all 26 bladder cancer tissue samples assayed. In tumour tissue, telomerase activity was not associated with tumour grade, size or stage. Telomerase activity in exfoliated urothelial cells from patients with bladder cancer was positive in 25 of 29 samples (86% sensitivity). The sensitivity of telomerase activity in exfoliated cells was seven of nine in G1, 10 of 12 in G2 and all eight G3 tumours; the corresponding sensitivity for voided urine cytology in G1, G2 and G3 tumours was two of nine, six of 12 and six of eight, respectively. CONCLUSION: These results indicate that telomerase activation occurs as an early step in carcinogenesis and the semi-quantitative analysis of telomerase activity in exfoliated urothelial cells could be a minimally invasive and useful method for detecting bladder cancer, even in low-grade tumours.

Aged↗

PubMed1998

Activation of the Ca2+-activated K+ channel via protein kinase A-dependent phosphorylation in human prostatic smooth muscle cells.

BACKGROUND: We investigated the functional importance of the Ca2+-activated K+ channel (K(Ca)-channel) of human prostatic smooth muscle cells in cyclic adenosine 3',5'-monophosphate (cAMP)-induced relaxation, to clarify signal transduction pathways and intracellular mechanisms of relaxation in prostatic smooth muscle. METHODS: Using the patch-clamp technique, we characterized the K(Ca)-channel of cultured human prostatic smooth muscle cells. We also investigated the effects on the K(Ca)-channels of forskolin, an activator of adenylate cyclase, amrinone, a phosphodiesterase inhibitor, and protein kinase A (A-kinase)-dependent phosphorylation. RESULTS: Single-channel current recordings from cultured human prostatic smooth muscle cells revealed the presence of K(Ca)-channels (conductance 296.7 +/- 5.67 pS, n = 7). In cell-attached patch configurations, the K(Ca)-channel was activated by forskolin (10(-4) mol/L) and amrinone (10(-4) mol/L). In inside-out patch configurations, it was activated by catalytic subunits of A-kinase (10 U/mL). CONCLUSIONS: We conclude that the K(Ca)-channel of human prostatic smooth muscle cells is regulated by intracellular cAMP levels and that A-kinase mediates the cAMP-induced activation of the K(Ca)-channel. This regulation of the K(Ca)-channel by cAMP may at least partially explain cAMP-induced prostatic smooth muscle relaxation and the effectiveness of certain drugs for treatment of obstruction in benign prostatic hyperplasia.

Adenylyl Cyclases↗