Abstract:
:Previous studies have demonstrated that the D-enantiomer of isoidide dinitrate (IIDN) is 10-fold more potent than the L-enantiomer for relaxation and cyclic GMP accumulation in isolated rat aorta. To test whether preferential biotransformation of D-IIDN to a species that activates guanylate cyclase is the basis for this observed enantioselectivity, paired segments of rat aorta were exposed to D- and L-IIDN and the tissue accumulation of the parent compound and the formation of their respective metabolites (D- and L-isoidide mononitrate, IIMN) were determined. The extent of relaxation of rat aorta following exposure to 2 microM D-IIDN was greater than that by L-IIDN over a 5-minute time course, and this was associated with a higher rate of D-IIDN biotransformation to D-IIMN at all time points. In addition, the rate of D-IIDN biotransformation was greater than that of L-IIDN at most IIDN concentrations tested. By contrast, the amount of D- and L-IIDN in the tissue was the same at all time points and concentrations tested, indicating that selective uptake of D-IIDN into blood vessels did not occur. When tissues were made tolerant to organic nitrate-induced relaxation by treatment with a high concentration of glyceryl trinitrate, the biotransformation of both D- and L-IIDN was attenuated. This suggests that mechanism-based biotransformation may be affected during tolerance development. Furthermore, the association of preferential D-IIDN biotransformation with its greater potency for vasodilation and cyclic GMP accumulation suggests than an enantioselective site for biotransformation is an important component of organic nitrate-induced vasodilation.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Stewart DH,Hayward LD,Bennett BMdoi
10.1139/y89-225subject
Has Abstractpub_date
1989-11-01 00:00:00pages
1403-8issue
11eissn
0008-4212issn
1205-7541journal_volume
67pub_type
杂志文章abstract::Cumulative data suggest the significant role of the renin-angiotensin system in the development of the pathological consequences of diabetes mellitus (DM). Newly synthesized AT2 receptor agonists gained importance as a target for creating new antihypertensives. The aim of the present work was to study the effects of p...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
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更新日期:1989-08-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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doi:10.1139/y85-207
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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pub_type: 杂志文章
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pub_type: 杂志文章
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-172
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y84-034
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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更新日期:2001-05-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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journal_title:Canadian journal of physiology and pharmacology
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更新日期:2000-11-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
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