Teacher:Given a passage, 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.
Teacher: Now, understand the problem? Solve this instance: We sought to define the mechanisms and correlates of leptin's vascular actions in humans with coronary artery disease.", "In 131 patients (age 65.7+/-0.7 years mean+/-SEM), ex vivo vascular reactivity to leptin (10(-13)-10(-7) M) was assessed in saphenous vein (SV) rings. Leptin led to SV relaxation (maximal relaxation 24.5+/-1.6%). In separate experiments, relaxation to leptin was unaffected by L-NMMA (17.4+/-3.4 vs.17.8+/-3.3%, P = 0.9) or endothelial denudation (17.4+/-4.4 vs. 22.5+/-3.0%, P = 0.4). We explored the possibility that leptin's vascular effects are mediated via smooth muscle hyperpolarization. In the presence of KCl (30 mmol/L) to inhibit hyperpolarization, the vasodilator effect of leptin was completely blocked (0.08+/-4.1%, P < 0.001 vs. control). Similar results were demonstrated in internal mammary artery rings. The only independent correlate of leptin-mediated vasodilatation was plasma TNF-alpha (r = 0.25, P < 0.05). Neither body mass index nor waist circumference correlated with leptin-mediated vasorelaxation. This lack of a correlation with markers of total body fat/fat distribution suggests that leptin resistance may not extend to the vasculature.
Student:
Is leptin an endothelial-independent vasodilator in humans with coronary artery disease : Evidence for tissue specificity of leptin resistance?