title: Vasopressin and angiotensin II stimulate oxygen uptake in the perfused rat hindlimb.
abstract: Vasopressin and angiotensin II markedly stimulated oxygen uptake in the perfused rat hindlimb. The increase due to each agent approached 70% of the basal rate, and was greater than that produced by a maximal concentration of norepinephrine. Half-maximal stimulation occurred at 60 pM vasopressin, 0.5 nM angiotensin II and 10 nM norepinephrine. Angiotensins I and III were less potent than angiotensin II. For each agent, the dose-dependent increase in oxygen uptake coincided with a dose-dependent increase in perfusion pressure. The effects of both vasopressin and angiotensin to increase oxygen uptake and pressure were not inhibited by either phentolamine, propranolol or a combination of the two, but were completely inhibited by the vasodilator, nitroprusside. Nitroprusside also inhibited flow-induced increases in hindlimb oxygen uptake and perfusion pressure. The findings indicate a key role for the vascular system in the control of hindlimb oxygen uptake.
authors.affiliation: Department of Biochemistry, University of Tasmania, Australia.
authors.forename: E Q
authors.initials: EQ
authors.lastname: Colquhoun
authors.forename: M
authors.initials: M
authors.lastname: Hettiarachchi
authors.forename: J M
authors.initials: JM
authors.lastname: Ye
authors.forename: E A
authors.initials: EA
authors.lastname: Richter
authors.forename: A J
authors.initials: AJ
authors.lastname: Hniat
authors.forename: S
authors.initials: S
authors.lastname: Rattigan
authors.forename: M G
authors.initials: MG
authors.lastname: Clark
mesh_terms: D000803:Angiotensin I / Q000494:pharmacology; D000804:Angiotensin II / Q000494:pharmacology*; D000805:Angiotensin III / Q000494:pharmacology; D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology*; D006614:Hindlimb / Q000098:blood supply; D008297:Male; D009599:Nitroprusside / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption / Q000187:drug effects*; D010646:Phentolamine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values
chemical_list: D000804:Angiotensin II; D001127:Arginine Vasopressin; D000805:Angiotensin III; D009599:Nitroprusside; D000803:Angiotensin I; D011433:Propranolol; D010100:Oxygen; D009638:Norepinephrine; D010646:Phentolamine