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Lázaro-Suárez, M.L., Gómez-Zamudio, J.H., Gallardo-Ortíz, I.A., Tanoue, A., Tsujimoto, G., Farias-Rodríguez, V.M. and Villalobos-Molina, R. (2005) Chloroethylclonidine Reveals That Alpha (1 A)-Adrenoceptors Mediate Contraction in Aorta of Alpha (1 D)-Adrenoceptor Knockout Mice. Autonomic and Autacoid Pharmacology, 25, 179-183.
https://doi.org/10.1111/j.1474-8673.2005.00348.x

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.