Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats
Ninety-six weanling male Wistar rats were fed for four weeks one of two different chows: a normal rat chow containing 55.5% (w/w) starch (control group, N = 48) or a rat chow in which starch was partially replaced by lactose, in such a way that the experimental group (N = 48) received 35.5% (w/w) st...
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| Format: | Article |
| Language: | English |
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Associação Brasileira de Divulgação Científica
1997-06-01
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| Series: | Brazilian Journal of Medical and Biological Research |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000600004 |
| _version_ | 1811324799519031296 |
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| author | E.A.L. da-Costa-Pinto E.F. Collares |
| author_facet | E.A.L. da-Costa-Pinto E.F. Collares |
| author_sort | E.A.L. da-Costa-Pinto |
| collection | DOAJ |
| description | Ninety-six weanling male Wistar rats were fed for four weeks one of two different chows: a normal rat chow containing 55.5% (w/w) starch (control group, N = 48) or a rat chow in which starch was partially replaced by lactose, in such a way that the experimental group (N = 48) received 35.5% (w/w) starch and 20% (w/w) lactose. The gastric emptying of fluid was then studied by measuring the gastric retention of four test meals containing lactose (5% or 10%, w/v) or glucose + galactose (5% or 10%, w/v). Homogenates of the small intestine were assayed for lactase activity. The gastric retention values were obtained 15 min after orogastric infusion of the liquid meals. The median values for gastric retention of the 5% lactose solutions were 37.7% for the control group and 37.0% for the experimental group (P>0.02). For the 10% lactose solution the median values were 51.2% and 47.9% (P>0.02) for the control and experimental groups, respectively. However, for the 2.5% glucose + 2.5% galactose meal the median gastric retention was lower (P<0.02) in the group fed a lactose-enriched chow (38.5%) than in the control group (41.6%). For the 5% glucose + 5% galactose solution the median values were not statistically different between groups, 65.0% for the control group and 58.8% for the experimental group. The median values of the specific lactase activity in the small intestine homogenate was 0.74 U/g in the control group and 0.91 U/g in the experimental group. These values were not statistically different (P>0.05). These results suggest that the prolonged ingestion of lactose by young adult rats changes the gastric emptying of a solution containing 5% monosaccharides. This adaptation may reflect the desensitization of intestinal nutrient receptors, possibly by an osmotic effect of lactose present in the chow. |
| first_indexed | 2024-04-13T14:20:47Z |
| format | Article |
| id | doaj.art-480404f7ec444f8ba2eeb32b3c634100 |
| institution | Directory Open Access Journal |
| issn | 0100-879X 1414-431X |
| language | English |
| last_indexed | 2024-04-13T14:20:47Z |
| publishDate | 1997-06-01 |
| publisher | Associação Brasileira de Divulgação Científica |
| record_format | Article |
| series | Brazilian Journal of Medical and Biological Research |
| spelling | doaj.art-480404f7ec444f8ba2eeb32b3c6341002022-12-22T02:43:28ZengAssociação Brasileira de Divulgação CientíficaBrazilian Journal of Medical and Biological Research0100-879X1414-431X1997-06-0130672310.1590/S0100-879X1997000600004Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling ratsE.A.L. da-Costa-PintoE.F. CollaresNinety-six weanling male Wistar rats were fed for four weeks one of two different chows: a normal rat chow containing 55.5% (w/w) starch (control group, N = 48) or a rat chow in which starch was partially replaced by lactose, in such a way that the experimental group (N = 48) received 35.5% (w/w) starch and 20% (w/w) lactose. The gastric emptying of fluid was then studied by measuring the gastric retention of four test meals containing lactose (5% or 10%, w/v) or glucose + galactose (5% or 10%, w/v). Homogenates of the small intestine were assayed for lactase activity. The gastric retention values were obtained 15 min after orogastric infusion of the liquid meals. The median values for gastric retention of the 5% lactose solutions were 37.7% for the control group and 37.0% for the experimental group (P>0.02). For the 10% lactose solution the median values were 51.2% and 47.9% (P>0.02) for the control and experimental groups, respectively. However, for the 2.5% glucose + 2.5% galactose meal the median gastric retention was lower (P<0.02) in the group fed a lactose-enriched chow (38.5%) than in the control group (41.6%). For the 5% glucose + 5% galactose solution the median values were not statistically different between groups, 65.0% for the control group and 58.8% for the experimental group. The median values of the specific lactase activity in the small intestine homogenate was 0.74 U/g in the control group and 0.91 U/g in the experimental group. These values were not statistically different (P>0.05). These results suggest that the prolonged ingestion of lactose by young adult rats changes the gastric emptying of a solution containing 5% monosaccharides. This adaptation may reflect the desensitization of intestinal nutrient receptors, possibly by an osmotic effect of lactose present in the chow.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000600004gastric emptyingintestinal motilitylactaselactose |
| spellingShingle | E.A.L. da-Costa-Pinto E.F. Collares Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats Brazilian Journal of Medical and Biological Research gastric emptying intestinal motility lactase lactose |
| title | Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats |
| title_full | Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats |
| title_fullStr | Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats |
| title_full_unstemmed | Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats |
| title_short | Chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats |
| title_sort | chronic lactose intake modifies the gastric emptying of monosaccharides but not of disaccharides in weanling rats |
| topic | gastric emptying intestinal motility lactase lactose |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000600004 |
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