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.

Neurotensin-1 (NT1) receptor agonists have been proposed as putative antipsychotic drugs. Recently, brain-penetrating NT analogs produced by stability-enhancing modification of the smallest NT fragment, NT(8-13), have demonstrated antipsychotic-like efficacy after acute systemic injection in several preclinical animal tests predictive for antipsychotic efficacy. However, the evidence regarding the persistence versus tolerance of these effects after repeated administration is ambiguous. Previous studies have used compounds that nonselectively activated both NT1 and NT2 receptors or used continuous slow, central infusion of doses rather than daily acute administration, both factors which may have contributed to the ambiguity in the literature regarding the emergence of tolerance.', 'To determine if tolerance develops to the antipsychotic-like effects of NT1 receptor agonists, we investigated the effects of subchronic daily systemic administration of PD149163, a brain-penetrating NT analog with selectivity for the NT1 receptor, on amphetamine-induced locomotor activation, a classic preclinical test of antipsychotic efficacy.', 'Sprague-Dawley rats were pretreated with eight consecutive daily subcutaneous (SC) injections of PD149163 or saline. On the ninth day, rats received a pair of SC injections consisting of PD149163 or saline, followed by amphetamine (0.5 mg/kg) or saline. Locomotor activity was then measured in photobeam-equipped cages.', "The results indicated that repeated daily administration of PD149163 was able to antagonize amphetamine's locomotor-activating effect comparable to that of the first dose, despite that repeated administration of PD149163 produced an increase in baseline locomotor activity not seen after the first dose.
Does the reversal of amphetamine-induced locomotor activation by a selective neurotensin-1 receptor agonist exhibit tolerance?

Bariatric surgery not only elicits weight loss but also rapidly resolves diabetes. However, the mechanisms remain unclear. The present study investigates how diabetes and liver steatosis are improved after duodenal-jejunal bypass (DJB) compared with a glucagon-like peptide-1 (GLP-1) analog and correlations between bile acids and GLP-1 secretion.', 'We initially determined the effects of bile acids on GLP-1 in vitro and then assigned 12 male 16-week-old Otsuka Long-Evans Tokushima Fatty rats to groups that underwent DJB, a sham operation, or were treated with the GLP-1 receptor agonist, liraglutide (n\u2009=\u20094 each). Blood glucose, insulin, GLP-1, serum bile acids, liver steatosis, and the number of GLP-1 positive cells (L cells) in the small intestine and colon were investigated in the three groups at eight weeks postoperatively.', 'Levels of GLP-1mRNA were upregulated and GLP-1 secretion increased in cells incubated with bile acids in vitro. Weight gain was suppressed more in the DJB than in the sham group in vivo. Diabetes was more improved and GLP-1 levels were significantly higher in the DJB than in the sham group. Serum bile acids were significantly increased, the number of L cells in the ileum was upregulated compared with the sham group, and liver steatosis was significantly improved in the DJB compared with the other two groups.
Does duodenal-jejunal bypass improve diabetes and liver steatosis via enhanced glucagon-like peptide-1 elicited by bile acids?

The sphingomyelin pathway is an important intracellular mechanism in regulating cell growth. The first step in this pathway is catalysed by sphingomyelinases. Alkaline sphingomyelinase is specifically located in the intestinal tract. Markedly reduced alkaline sphingomyelinase activities have been found in sporadic colorectal tumours and in familial adenomatous polyposis adenomas. Since the adenomatous polyposis coli (APC) gene is mutated in about 80% of sporadic colorectal tumors, and familial adenomatous polyposis is the consequence of a germline mutation of the same gene, we examined whether low alkaline sphingomyelinase activity is linked to APC gene mutations.', 'Both germline and sporadic adenomatous polyposis coli gene mutations were studied. Alkaline, neutral, and acid sphingomyelinase activities were measured in the intestinal mucosa and content of multiple intestinal neoplasia mice, a murine model of familial adenomatous polyposis and compared to control mice. Alkaline sphingomyelinase activity was also measured in 11 human rectal tumors with APC gene mutation and compared with 9 control tumors without mutation.', 'Alkaline, neutral, and acid sphingomyelinase activities were present in the small intestine and colon in both mice types with no differences in hydrolytic capacity or distribution pattern. In sporadic rectal tumors similar alkaline sphingomyelinase activities were identified in tumors with somatic APC gene mutations as in samples without mutations. In the tumors without detectable APC mutations beta-catenin was analyzed, but no mutation was detected.

Is reduction in alkaline sphingomyelinase in colorectal tumorigenesis related to the APC gene mutation?