Enhanced myogenic response in resistance small arteries from spontaneously hypertensive rats: relationship to the voltage-dependent calcium channel
| Autor: | Jun Shibuya, Mitsumasa Ohyanagi, Tadaaki Iwasaki |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
medicine.medical_specialty
Myogenic contraction chemistry.chemical_element Calcium In Vitro Techniques Rats Inbred WKY Calcium in biology Muscle Smooth Vascular Nitrendipine Internal medicine Rats Inbred SHR Internal Medicine medicine Pressure Animals Antihypertensive Agents Voltage-dependent calcium channel business.industry Calcium channel Anatomy Mesenteric Arteries Rats Endocrinology medicine.anatomical_structure chemistry Vasoconstriction Cremaster muscle Vascular Resistance Calcium Channels business Artery medicine.drug Muscle Contraction |
| Zdroj: | American journal of hypertension. 11(7) |
| ISSN: | 0895-7061 |
| Popis: | To characterize the myogenic response during the development of hypertension, we evaluated the myogenic response of small arteries isolated from the cremaster muscle of spontaneously hypertensive rats (SHR) aged 4-5 and 7-8 weeks, as compared with age-matched Wistar-Kyoto rats (WKY), using an in vitro system. The myogenic response of SHR aged 7-8 weeks (but not those aged 4-5 weeks) significantly exceeded that of WKY. Measurement of intracellular levels of free calcium ([Ca 2+ ] i ) in small arteries of the 7-8-week-old SHR and WKY loaded with a calcium-sensitive dye showed that the increase in [Ca 2+ ] i in SHR was significantly greater than that in WKY during the myogenic response. The inhibitory effects of nitrendipine on the increased myogenic response and [Ca 2+ ] i were greater in SHR. Thus, the myogenic response was enhanced in SHR and may be explained in part by an increase in Ca 2+ entry through the voltage-dependent calcium channel (VDCC). The myogenic response and Ca 2+ entry through the VDCC may be increased in association with the elevation of blood pressure. Am J Hypertens 1998;11:767-773 © 1998 American Journal of Hypertension, Ltd. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|