Publications by authors named "Yukinao Yamauchi"

We have prepared a series of quinazolinone derivatives linked with piperazinylquinoline for the treatment of irritable bowel syndrome (IBS). Using pharmacophore analysis, we designed and synthesized compounds which bind to both serotonin receptor subtype 1A (5-HT(1A)) and subtype 3 (5-HT(3)). Quinazolinone derivatives with a sulfur atom in the linker showed high affinity in in vitro assays, but low in vivo activity.

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Article Synopsis
  • Researchers developed piperazinylpyridine derivatives aimed at treating irritable bowel syndrome (IBS), focusing on specific receptor interactions.
  • The compounds were designed using pharmacophore analysis, highlighting crucial elements like the nitrogen atom of isoquinoline, a methoxy group, and piperazine for effective receptor binding.
  • One promising compound, TZB-20810, showed strong affinity for serotonin receptors and exhibited both agonistic and antagonistic properties, indicating its potential as a therapeutic option for IBS.
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3-Amino-5,6,7,8-tetrahydro-2-[4-[4-(quinolin-2-yl)piperazin-1-yl]butyl]quinazolin-4(3H)-one (TZB-30878) is a novel compound with both 5-hydroxytryptamine (5-HT)(1A) agonism and 5-HT(3) antagonism effects. We hypothesized that TZB-30878 might have benefits from these dual effects as a medication for diarrhea-predominant irritable bowel syndrome (d-IBS), and these studies were designed to confirm the pharmacological properties of TZB-30878 and its efficacy in an IBS-like animal model. The binding assays demonstrated that [(3)H]TZB-30878 selectively binds to human 5-HT(1A) and 5-HT(3) receptors, with K(d) values of 0.

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Purpose: Arginase shares L-arginine as a common substrate with nitric oxide (NO) synthase (NOS). We examined whether increased arginase activity is involved in impaired cavernous relaxation with aging in the rabbit.

Materials And Methods: Young adult (3 to 5 months old) and aged (36 to 48 months old) rabbits were used for the current experiments.

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Purpose: We investigated the possible role of the endogenous nitric oxide (NO) synthase (NOS) inhibitors N-monomethyl-L-arginine (L-NMMA) and asymmetrical N, N-dimethyl-L-arginine (ADMA) in inhibiting urethral relaxation following estrogen supplementation in ovariectomized rabbits.

Materials And Methods: A total of 16 mature Japanese White female rabbits were divided into 2 groups. In the control group rabbits were sacrificed 2 weeks after bilateral ovariectomy.

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In postmenopausal breast cancer tissue, steroid sulfatase (STS) activity is high and much estrone sulfate also exists; these facts reveal that estrone sulfate may be involved in the growth of breast cancer as an estrogen source. Steroid sulfatase is an enzyme, which catalyzes hydrolysis from estrone sulfate to estrone, and the development of steroid sulfatase inhibitors is expected as novel therapeutic drugs for postmenopausal breast cancer. We have developed a novel compound 2',4'-dicyanobiphenyl-4-O-sulfamate (TZS-8478), which has potent steroid sulfatase-inhibitory activity and exhibits no estrogenicity in vitro and in vivo.

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Danazol and gonadotropin-releasing hormone agonists which are used as therapeutic drugs for endometriosis, develop adverse reactions in association with their long-term use. The efficacy of anti-estrogens for endometriosis, an estrogen-dependent disorder, has not been demonstrated. A novel, orally active anti-estrogen, TZE-5323 ((2-cyclohexy-6-hydroxybenzo[b]thien-3-yl)[4-[2-(1- piperidinyl)ethoxy]phenyl] methanone hydrochloride, CAS 150797-71-0; free salt formula) was developed.

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Present experiments were designed to investigate whether the facilitated polyol pathway is involved in the augmentation of intimal hyperplasia with hyperglycemia. Twelve weeks after a single bolus intravenous injection of alloxan (100 mg/kg) or saline, rabbits underwent a unilateral endothelial denudation of the carotid artery. Intimal hyperplasia was evident 4 weeks after denudation and significantly augmented in hyperglycemic animals treated with alloxan.

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Endothelin (ET)-1, which had been discovered as the most potent vasoconstrictive peptide, plays active roles in the various biological responses. However, it is controversial how is ET-1 involved in the vascular remodeling process. Therefore, present experiments were performed to investigate the role of ET-1 for the initiation/progression of intimal hyperplasia.

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