Given the task definition and input, reply with output. Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Context: To examine the effect of angiotensin-converting enzyme inhibitor (ACEI) on hydrogen peroxide (H(2)O(2))-induced decrease in contraction of isolated rataortic rings, and to investigate its mechanisms.', 'The thoracic aortic rings with endothelium of male Sprague-Dawley rats were mounted on a bath system. Isometric contractions of aortic rings were measured.', '(1) After incubation with captopril (an ACEI with sulfhydryl groups) or perindoprilate (an ACEI without sulfhydryl groups), the decrease in contraction response to PE was prevented in arteries which were pretreated with 300 micromol/L H(2)O(2). (2) Captopril enhanced the HO-1 activity of thoracic aorta. After inhibition of HO-1 activity by ZnPP IX, the protection effect of captopril was abrogated. Hemin (an inducer of HO-1) and bilirubin (a product of HO-1) could mimic the antioxidative effect of captopril. (3) Both L-NAME (an inhibitor of NOS) and methylene blue (an inhibitor of GC) could abolish the protective effect of captopril. (4) SNAP could protect aortic rings against H(2)O(2) attack, and ZnPP IX could cancel the effect of SNAP.
Answer: Both ACEI with or without sulfhydryl groups could prevent the H(2)O(2) induced decrease in contraction responses to PE in intact aortic rings. The increase of NO and activation of HO-1 might be involved in the mechanism.
Does [ Nitric oxide/heme oxygenase-1 mediate the antioxidant effect of ACEI in rat aortic rings ]?