title: Interaction between norepinephrine release and intrarenal angiotensin II formation during renal nerve stimulation in dogs.
abstract: We examined possible interactions between intrarenal angiotensin II (ANG II) formation and norepinephrine (NE) release during renal sympathetic nerve stimulation (RNS) in anesthetized dogs. During 10 min of continuous RNS (1.5-2 Hz), the ANG II formation rates (ANG II-FR) and NE secretion rates (NE-SR) were determined at 1 and 10 min. Under control conditions, almost the same extent of increase in the NE-SR was observed at 1 and 10 min of RNS, whereas a significant increase in ANG II-FR was observed at 10 min but not at 1 min. During intrarenal arterial infusion of enalaprilat or losartan, the increase in NE-SR and reduction in renal blood flow at 10 min of RNS were suppressed, whereas the NE release and vasoconstriction responses at 1 min remained unaffected. The RNS-induced increases in ANG II-FR were completely abolished during infusion of enalaprilat. These results suggest that NE release on continuous RNS is enhanced by concomitantly formed ANG II, and this interaction depends on the time-related changes in intrarenal ANG II formation during RNS in the canine kidney.
authors.affiliation: Laboratory of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Aobayama, Sendai, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Yamaguchi
authors.forename: M
authors.initials: M
authors.lastname: Suzuki-Kusaba
authors.forename: H
authors.initials: H
authors.lastname: Hisa
authors.forename: Y
authors.initials: Y
authors.lastname: Hayashi
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: S
authors.initials: S
authors.lastname: Satoh
mesh_terms: D000804:Angiotensin II / Q000096:biosynthesis* / Q000097:blood / Q000494:pharmacology; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D004285:Dogs; D015773:Enalaprilat / Q000494:pharmacology; D005260:Female; D007668:Kidney / Q000187:drug effects / Q000294:innervation* / Q000378:metabolism*; D019808:Losartan / Q000494:pharmacology; D008297:Male; D009638:Norepinephrine / Q000097:blood / Q000378:metabolism*; D012079:Renal Circulation / Q000187:drug effects; D013564:Sympathetic Nervous System / Q000502:physiology; D013997:Time Factors
chemical_list: D000959:Antihypertensive Agents; D000804:Angiotensin II; D015773:Enalaprilat; D019808:Losartan; D009638:Norepinephrine