In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

[Q]: Context: Opioid-induced spastic paraplegia after transient spinal cord ischemia during aortic surgery has been reported. Opioids modulate neurotransmission through mu () opioid receptors (MORs) in the spinal ventral horn. However, their effects during ischemic insult are not understood.', 'The effects of the selective agonist [D-Ala(2),-N-Me-Phe(4), Gly(5)-ol]enkephalin (DAMGO) on ischemia-induced agonal currents were examined in the spinal lamina IX neurons of neonatal rats by using the whole-cell patch-clamp technique. Ischemia was simulated in vitro by oxygen/glucose deprivation.', 'DAMGO (1 M) produced outward currents in ~60% of spinal lamina IX neurons at a holding potential of -70 mV. Superfusion with ischemia-simulating medium elicited an agonal current. The latency was 457 18 s. Despite its neuromodulatory effects, DAMGO did not significantly change the latencies of the agonal currents with (440 23 s) or without (454 33 s) DAMGO-induced currents.\Question: Does the mu opioid receptor activation affect ischemia-induced agonal currents in rat spinal ventral horn?
[A]: Activation of MORs does not influence ongoing ischemia-induced neuronal death. Our findings indicate that MOR agonist administration should be suitable as an anesthetic during aortic surgery.

[Q]: Context: Approximately 50% of subjects with essential hypertension (EH) are insulin resistant, and this defect in insulin action could contribute to increased cardiovascular disease (CVD) risk in these patients. To test this hypothesis, we attempted to see if there was a link between insulin resistance (IR) and carotid intimal medial thickness (IMT), an early index of CVD, in patients with essential hypertension.', 'Ultrasound quantification of carotid IMT was performed in 79 hypertensive patients, and 63 patients (31 m and 32 f), defined as being free of plaque (IMT < 1.3 mm), were further subdivided into normal (<1.0 mm) and thickened (1-1.3 mm) IMT groups. Subjects in the thickened IMT group were older and had significantly (p < 0.05) higher plasma concentrations of fasting insulin, nitric oxide (NO(x)) and intercellular adhesion molecule 1 (ICAM-1). However, the two groups were not significantly different in terms of blood pressure, overall or regional obesity, fasting lipid levels, uric acid, concentrations of other cellular adhesion molecules or levels of C-reactive protein. There were significant (p < 0.05) correlations in the whole population between IMT and age, fasting insulin and NO(x), and multiple regression analysis identified fasting insulin as an independent predictor of IMT.\Question: Do insulin resistance/compensatory hyperinsulinemia predict carotid intimal medial thickness in patients with essential hypertension?
[A]: The presence of increased IMT is significantly related to several metabolic and endothelial abnormalities associated with IR/hyperinsulinemia, and fasting insulin independently predicts the thickness of the intima-media layer. These results support the view that CVD risk is greatest in those patients with essential hypertension who are also IR/hyperinsulinemic.

[Q]: Context: To investigate the alteration of the retinal nerve fiber thickness (NFLT) before and after vitreous surgery for a macular hole in cases with or without visual field defects.', 'The NFLT of 23 eyes with idiopathic macular hole was measured with scanning laser polarimeter upto 12 months after surgery. The NFLT was divided into superior, inferior, nasal, and temporal quadrants. The mean NFLT of each quadrant was analyzed statistically and compared to the results of visual field tests.', 'In all cases, the NFLT decreased significantly upto 3 months after surgery, but increased gradually upto 12 months. In cases with visual field loss, the thickness of the nerve fiber layer that corresponds to the visual field defect diminished strongly, in contrast with other quadrants. Even in cases without visual field loss, the NFLT decreased significantly a month after surgery, especially in the nasal and inferior quadrants.\Question: Does [ Thickness of retinal nerve fiber layer decrease after vitreous surgery for idiopathic macular hole ]?
[A]:
This study demonstrates that the thickness of retinal nerve fiber layer decreases at least one month after surgery, even in cases without visual field defect. This fact may suggest the existence of a subclinical complication of vitreous surgery.