Role of nitric oxide and cyclooxygenase products in controlling vascular tone in uterine microvessels of rats
| Autor: | M. K. Henzel, E. F. Asher, N. L. Alsip, P. R. Saha |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
Serotonin
Embryology medicine.medical_specialty Vasodilator Agents Prostaglandin Ibuprofen Video microscopy Nitric Oxide Nitroarginine Nitric oxide Rats Sprague-Dawley Phenylephrine chemistry.chemical_compound Endocrinology Internal medicine medicine Animals Fiber Optic Technology Vasoconstrictor Agents Cyclooxygenase Inhibitors Enzyme Inhibitors Microscopy Video biology Chemistry Angiotensin II Microcirculation organic chemicals Uterus Hemodynamics Obstetrics and Gynecology Cell Biology Acetylcholine Rats Nitric oxide synthase Reproductive Medicine Prostaglandin-Endoperoxide Synthases Dilator biology.protein Female Cyclooxygenase Nitric Oxide Synthase medicine.symptom Vasoconstriction |
| Zdroj: | Reproduction. 112:211-216 |
| ISSN: | 1741-7899 1470-1626 |
| DOI: | 10.1530/jrf.0.1120211 |
| Popis: | The importance of nitric oxide (NO) and dilator prostaglandins in uterine resistance arterioles was investigated. In pentobarbital anaesthetized rats at dioestrus-2, the uterine microcirculation in vivo was transilluminated by a fibreoptic probe and microvessels (circumferential arterioles) viewed by video microscopy. Arteriolar diameters were measured while increasing concentrations of acetylcholine (ACh), serotonin (5-HT), phenylephrine (PE), or angiotensin II (AII) were applied topically (suffused) over the uterus. Agonists were applied alone or with ibuprofen (IBU; cyclooxygenase inhibitor), N\g=w\-nitro-L-arginine(L-NA; nitric oxide synthase inhibitor) or both. Circumferential arterioles were dilated by ACh and 5-HT (10\m=-\8\p=n-\10\m=-\4mol l\m=-\1) and constricted by PE (10\m=-\8\p=n-\10\m=-\5 mol l\m=-\1) and AII (10\m=-\11\p=n-\10\m=-\7 mol l\m=-\1). Suffusion of L-NA or L-NA with ibuprofen (10 \m=-\4 mol l\m=-\1 each) abolished ACh-induced dilation; ibuprofen alone blocked dilation at higher ACh concentrations. Serotonin-induced relaxation was significantly attenuated by L-NA alone or in combination with ibuprofen. Vasoconstriction induced by PE was enhanced by L-NA alone and L-NA with ibuprofen, but ibuprofen alone had no effect. In contrast, AII-induced constriction was enhanced significantly by ibuprofen or L-NA and further enhanced when both ibuprofen and L-NA were present. These results suggest that ACh can release either nitric oxide (NO) or cyclooxygenase products to cause uterine arteriolar dilation and that 5-HT-induced uterine microvascular relaxation is mediated via NO only. They also suggest that PE-induced vasoconstriction is attenuated by the release of NO but not cyclooxygenase products and that constrictor responses evoked by AII are attenuated by both NO and dilator prostaglandin release. Thus, both nitric oxide and dilator prostaglandins are important in the control of uterine microvessels. |
| Databáze: | OpenAIRE |
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