Source Paper
Source Paper
Journal of Clinical Investigation • 1996
We tested the hypothesis that angiotensin II-induced hypertension is associated with an increase in vascular.O2- production, and characterized the oxidase involved in this process. Infusion of angiotensin II (0.7 mg/kg per d) increased systolic blood pressure and doubled vascular.O2- production (assessed by lucigenin chemiluminescence), predominantly from the vascular media. NE infusion (2.75 mg/kg per d) produced a similar degree of hypertension, but did not increase vascular.O2- production. Studies using various enzyme inhibitors and vascular homogenates suggested that the predominant source of.O2- activated by angiotensin II infusion is an NADH/NADPH-dependent, membrane-bound oxidase. Angiotensin II-, but not NE-, induced hypertension was associated with impaired relaxations to acetylcholine, the calcium ionophore A23187, and nitroglycerin. These relaxations were variably corrected by treatment of vessels with liposome-encapsulated superoxide dismutase. When Losartan was administered concomitantly with angiotensin II, vascular.O2- production and relaxations were normalized, demonstrating a role for the angiotensin type-1 receptor in these processes. We conclude that forms of hypertension associated with elevated circulating levels of angiotensin II may have unique vascular effects not shared by other forms of hypertension because they increase vascular smooth muscle.O2- production via NADH/NADPH oxidase activation.
Objective: To test the hypothesis that angiotensin II-induced hypertension is associated with increased vascular superoxide production and to characterize the oxidase involved, and to demonstrate the role of angiotensin type-1 receptor in these processes using Losartan co-administration
This is a Losartan Co-administration Study protocol using rat as the model organism. The procedure involves 7 procedural steps, 3 equipment items, 9 materials. Extracted from a 1996 paper published in Journal of Clinical Investigation.
Model and subjects
rat • Not specified • unknown • Not specified • Not specified
Study window
Estimated timing pending
Core workflow
Angiotensin II infusion • Norepinephrine infusion control • Measure vascular superoxide production
Primary readouts
Key equipment and reagents
Verified items
0
Direct vendor links
0
Use this page as an execution guide, then fall back to the source paper whenever you need exact exclusions, dosing details, or assay-specific caveats.
Confirm first
Use the page like this
Start here. The step list is optimized for running the experiment, with direct vendor links available inline when you need to source a cited item.
Infuse angiotensin II to induce hypertension and measure resulting vascular superoxide production
Note: Dose: 0.7 mg/kg per day. This treatment increased systolic blood pressure and doubled vascular superoxide production
“Infusion of angiotensin II (0.7 mg/kg per d) increased systolic blood pressure and doubled vascular.O2- production”
Infuse norepinephrine as a control hypertensive agent to compare vascular effects
Note: Dose: 2.75 mg/kg per day. Produced similar degree of hypertension but did not increase vascular superoxide production
“NE infusion (2.75 mg/kg per d) produced a similar degree of hypertension, but did not increase vascular.O2- production”
Assess vascular superoxide production using lucigenin chemiluminescence, with focus on vascular media
Note: Superoxide production was predominantly from the vascular media
“doubled vascular.O2- production (assessed by lucigenin chemiluminescence), predominantly from the vascular media”
Use various enzyme inhibitors and vascular homogenates to characterize the oxidase source
Note: Studies identified the predominant source as an NADH/NADPH-dependent, membrane-bound oxidase
“Studies using various enzyme inhibitors and vascular homogenates suggested that the predominant source of.O2- activated by angiotensin II infusion is an NADH/NADPH-dependent, membrane-bound oxidase”
Test vascular relaxations to acetylcholine, calcium ionophore A23187, and nitroglycerin
Note: Angiotensin II-induced hypertension was associated with impaired relaxations to these agents, while NE-induced hypertension was not
“Angiotensin II-, but not NE-, induced hypertension was associated with impaired relaxations to acetylcholine, the calcium ionophore A23187, and nitroglycerin”
Treat vessels with liposome-encapsulated superoxide dismutase to assess correction of impaired relaxations
Note: Relaxations were variably corrected by this treatment, supporting superoxide involvement
“These relaxations were variably corrected by treatment of vessels with liposome-encapsulated superoxide dismutase”
Administer Losartan concomitantly with angiotensin II to determine angiotensin type-1 receptor involvement
Note: Losartan co-administration normalized both vascular superoxide production and relaxations
“When Losartan was administered concomitantly with angiotensin II, vascular.O2- production and relaxations were normalized, demonstrating a role for the angiotensin type-1 receptor”
This section explains what the experiment is doing, which readouts matter, what the data artifacts usually look like, and how the analysis should flow from raw capture to reported result.
To test the hypothesis that angiotensin II-induced hypertension is associated with increased vascular superoxide production and to characterize the oxidase involved, and to demonstrate the role of angiotensin type-1 receptor in these processes using Losartan co-administration
Objective
To test the hypothesis that angiotensin II-induced hypertension is associated with increased vascular superoxide production and to characterize the oxidase involved, and to demonstrate the role of angiotensin type-1 receptor in these processes using Losartan co-administration
Subjects
From paperrat • Not specified • unknown • Not specified • Not specified
Cohort notes
From paperNone specified
Angiotensin II infusion (Not specified)
Norepinephrine infusion control (Not specified)
Measure vascular superoxide production (Not specified)
Enzyme inhibitor studies (Not specified)
Systolic blood pressure
From paperNot specified in the provided text
Artifact type
Endpoint measurements summarized by group or timepoint
Comparison focus
Compare endpoint magnitude between groups, timepoints, or both
Vascular superoxide production (measured by lucigenin chemiluminescence)
From paperNot specified in the provided text
Artifact type
Endpoint measurements summarized by group or timepoint
Comparison focus
Compare endpoint magnitude between groups, timepoints, or both
Vascular relaxation responses to acetylcholine
From paperNot specified in the provided text
Artifact type
Endpoint measurements summarized by group or timepoint
Comparison focus
Compare endpoint magnitude between groups, timepoints, or both
Vascular relaxation responses to calcium ionophore A23187
From paperNot specified in the provided text
Artifact type
Endpoint measurements summarized by group or timepoint
Comparison focus
Compare endpoint magnitude between groups, timepoints, or both
Systolic blood pressure
From paperRaw artifact
Per-sample or per-animal endpoint measurements collected during the experiment
Processed artifact
Structured table with cleaned measurements ready for comparison
Final reported form
Summary statistics and between-group or across-timepoint comparisons
Vascular superoxide production (measured by lucigenin chemiluminescence)
From paperRaw artifact
Per-sample or per-animal endpoint measurements collected during the experiment
Processed artifact
Structured table with cleaned measurements ready for comparison
Final reported form
Summary statistics and between-group or across-timepoint comparisons
Vascular relaxation responses to acetylcholine
From paperRaw artifact
Per-sample or per-animal endpoint measurements collected during the experiment
Processed artifact
Structured table with cleaned measurements ready for comparison
Final reported form
Summary statistics and between-group or across-timepoint comparisons
Vascular relaxation responses to calcium ionophore A23187
From paperRaw artifact
Per-sample or per-animal endpoint measurements collected during the experiment
Processed artifact
Structured table with cleaned measurements ready for comparison
Final reported form
Summary statistics and between-group or across-timepoint comparisons
Acquisition
Collect raw experimental outputs with enough metadata to preserve sample identity, condition, and timing.
Preprocessing / cleaning
Not specified in the provided text
Scoring or quantification
Quantify the primary readouts for this experiment: Systolic blood pressure; Vascular superoxide production (measured by lucigenin chemiluminescence); Vascular relaxation responses to acetylcholine; Vascular relaxation responses to calcium ionophore A23187.
Statistical comparison
Statistical method not yet structured for this page.
Reporting output
Report representative outputs alongside summary comparisons for Systolic blood pressure, Vascular superoxide production (measured by lucigenin chemiluminescence), Vascular relaxation responses to acetylcholine, Vascular relaxation responses to calcium ionophore A23187.
Source links and direct wording from the methods section for validation and deeper review.
Citation
S Rajagopalan et al. (1996). Angiotensin II-mediated hypertension in the rat increases vascular superoxide production via membrane NADH/NADPH oxidase activation. Contribution to alterations of vasomotor tone.. Journal of Clinical Investigation
“”
“”
“”
“”
Direct vendor pages are linked from the protocol above. This section stays focused on the full comparison view and the prep checklist.
Gather these items before starting the experiment. Check off items as you prepare.
Not specified • Not specified • Not specified • Not mentioned
Not specified • Not specified • Not specified • Not mentioned
Not specified • Not specified • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
Not specified • Not applicable • Not specified • Not mentioned
1 item with ReplicateScience direct pages
Estimated: $1,490.00
Use this section as the page quality checkpoint. It keeps section navigation, evidence access, readiness, and verification meaning in one place.
Current status surfaces were computed from experiment data updated Feb 28, 2026.
Source access
Jump back into the original paper or the methods evidence section when you need exact wording, exclusions, or method-specific caveats.
This protocol has structured steps plus evidence quotes, and is ready for canonical sync.
Steps
7
Evidence Quotes
19
Protocol Items
12
Linked Products
1
Canonical Sync
Pending
What this means
The completeness score reflects how much structured protocol data is present: steps, methods evidence, listed materials, linked products, and paper provenance.
Computed from the current experiment record updated Feb 28, 2026.
Canonical Sync shows whether a ConductGraph-backed protocol is available for this experiment route right now. It is a sync-status signal, not a claim that every downstream vendor link or step detail is perfect.
Steps
7
Evidence
19
Specific Products
1/1
Canonical Sync
Pending
What this score means
The verification score reflects evidence coverage, subject detail, paper provenance, step depth, and whether linked products resolve to specific item pages instead of generic searches.
Computed from the current experiment record updated Feb 28, 2026.
A page can have structured steps and still need review when evidence is thin, product links are generic, or canonical protocol coverage is still pending.