Abstract
Presynaptic angiotensin II (AII) receptor-mediated facilitation of vascular adrenergic neurotransmission was studied in the in situ, blood-perfused mesentery of 13- to 16-week-old spontaneously hypertensive rats (SHR) and age-matched normotensive Wistar Kyoto rats (WKY). Mesenteric arterial perfusion pressure frequency-response curves to periarterial adrenergic nerve stimulation (PNS) and dose-response curves to exogenous norepinephrine (NE) were obtained in SHR and WKY. The effects of the following treatments on the mesenteric vascular perfusion pressure responses (PPR) to PNS and NE were studied: All alone infused i.a. at 1 and 5 ng/min; All infused at 5 ng/min after [Sar1-lle8]All infused at 20 ng/min; [Sar1-lle8]All infused at 20 ng/min alone; captopril alone at 0.1 mg/kg i.v.; All infused i.a. at 0.3 and 1 ng/min after captopril at 0.1 mg/kg and angiotensin I injected at 3 dose levels after captopril at 0.1 mg/kg. Control PPR to PNS and NE were greater in SHR than in WKY. Comparisons of PPR in SHR to those in WKY were made, therefore, at the predetermined PPR levels of 15, 20, 30, 40, 50, 60 and 70 mm Hg. All alone shifted the PNS frequency-response curve to the left to a greater extent in the SHR than in the WKY when infused at 5 ng/min but not when infused at 1 ng/min. Both infusion rates of All had significantly different effects on the dose-response curves to NE in WKY and SHR. The effects of All infusion (5 ng/min) on both the response to PNS and to NE were antagonized completely by the concurrent infusion of [Sar1-lle8] All at 20 ng/min.(
ABSTRACT
TRUNCATED AT 250 WORDS)
TY - JOUR
T1 - Enhanced in vivo responsiveness of presynaptic angiotensin II receptor-mediated facilitation of vascular adrenergic neurotransmission in spontaneously hypertensive rats.
A1 - Cline,W H,Jr
PY - 1985/3/1/pubmed
PY - 2001/3/28/medline
PY - 1985/3/1/entrez
SP - 661
EP - 9
JF - The Journal of pharmacology and experimental therapeutics
JO - J Pharmacol Exp Ther
VL - 232
IS - 3
N2 - Presynaptic angiotensin II (AII) receptor-mediated facilitation of vascular adrenergic neurotransmission was studied in the in situ, blood-perfused mesentery of 13- to 16-week-old spontaneously hypertensive rats (SHR) and age-matched normotensive Wistar Kyoto rats (WKY). Mesenteric arterial perfusion pressure frequency-response curves to periarterial adrenergic nerve stimulation (PNS) and dose-response curves to exogenous norepinephrine (NE) were obtained in SHR and WKY. The effects of the following treatments on the mesenteric vascular perfusion pressure responses (PPR) to PNS and NE were studied: All alone infused i.a. at 1 and 5 ng/min; All infused at 5 ng/min after [Sar1-lle8]All infused at 20 ng/min; [Sar1-lle8]All infused at 20 ng/min alone; captopril alone at 0.1 mg/kg i.v.; All infused i.a. at 0.3 and 1 ng/min after captopril at 0.1 mg/kg and angiotensin I injected at 3 dose levels after captopril at 0.1 mg/kg. Control PPR to PNS and NE were greater in SHR than in WKY. Comparisons of PPR in SHR to those in WKY were made, therefore, at the predetermined PPR levels of 15, 20, 30, 40, 50, 60 and 70 mm Hg. All alone shifted the PNS frequency-response curve to the left to a greater extent in the SHR than in the WKY when infused at 5 ng/min but not when infused at 1 ng/min. Both infusion rates of All had significantly different effects on the dose-response curves to NE in WKY and SHR. The effects of All infusion (5 ng/min) on both the response to PNS and to NE were antagonized completely by the concurrent infusion of [Sar1-lle8] All at 20 ng/min.(ABSTRACT TRUNCATED AT 250 WORDS)
SN - 0022-3565
UR - https://www.unboundmedicine.com/medline/citation/2983066/Enhanced_in_vivo_responsiveness_of_presynaptic_angiotensin_II_receptor_mediated_facilitation_of_vascular_adrenergic_neurotransmission_in_spontaneously_hypertensive_rats_
L2 - https://jpet.aspetjournals.org/cgi/pmidlookup?view=long&pmid=2983066
DB - PRIME
DP - Unbound Medicine
ER -
