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Nishimura (Hano), T., Nishio, I., Ohtani, H., Jimbo, S., Kuchii, M. and Masuyama, Y. (1979) Plasma Catecholamines Determination Using High Pressure Liquid Chromatography and Their Roles in Blood Pressure Regulation and Experimental Hypertension in Rats. Japanese Circulation Journal, 43, 855-865.
https://doi.org/10.1253/jcj.43.855

has been cited by the following article:

• TITLE: Altered Calcium Handling in Peripheral Nerve Terminals and Blood Vessels in Spontaneously Hypertensive Rats

  AUTHORS: Naomi Iwane, Yumi Koike, Takuzo Hano

  KEYWORDS: Hypertension, Calcium, Sympathetic Nerve, Blood Vessel

  JOURNAL NAME: Health, Vol.9 No.2, February 21, 2017

  ABSTRACT: The present study was designed to clarify the roles of N-type and P/Q-type calcium channels in the increased sympathetic activity of spontaneously hypertensive rats (SHR/Izm). We also tested in SHR/Izm the contribution to increased vascular tone of α1A adrenoceptor-linked L-type calcium channels and α1B receptor-mediated calcium mobilization from the sarcoplasmic reticulum. Methods: Six-week-old SHR/Izm and Wistar-Kyoto rats (WKY/Izm) were used. A superior mesenteric arterial preparation was electrically stimulated before and after treatment with ω-conotoxin GVIa (N-type calcium channel blocker [CgTX]) and ω-agatoxinIVa (P/Q-type calcium channel blocker [AgaTX]). Pressor response to norepinephrine was measured before and after treatment with the α1A blocker WB-4101 and the α1B blocker chloroethyl clonidine (CEC). To determine the intracellular calcium store size, the effects of ryanodine on pressor response and caffeine-induced vascular contraction were also tested. Results: Norepinephrine overflow evoked by electrical stimulation was increased in SHR/Izm. CgTX but not AgaTX suppressed the increased NE overflow in SHR/Izm. WB-4101 suppressed the pressor response to norepinephrine in SHR/Izm but not WKY/Izm rats. CEC had no effects on pressor response to norepinephrine in both types of rats. Caffeine-induced contraction to a high potassium-induced maximal contraction ratio was reduced in SHR/Izm. The effect of ryanodine on pressor response was reduced in SHR/Izm. Conclusion: N-type calcium channels but not P/Q-type calcium channels play an important role in the increased sympathetic tone in SHR/ Izm. Although α1A adrenoceptor-linked L-type calcium channels contribute to the increased vascular tone, the intracellular calcium store size was reduced in SHR/Izm.