Biomedical subjects

J M Rayó

Publications and source records attributed to J M Rayó.

9 recordsLinked to original sources

PubMed1994

Disaccharidase activities in pregnant and lactating rats.

The changes in intestinal disaccharidase activities in pregnancy and lactation could be explained as a result of an adaptation to the energy demands of each reproductive stage. To examine these changes, disaccharidase activities (lactase, sucrase, maltase, and trehalase) were measured in the jejunum and ileum of virgin, pregnant and lactating Wistar rats. Minor changes in disaccharidase activities were observed in pregnancy, whereas an increase of disaccharidase activities per small intestine length normalized to body mass was observed in lactation.

Animals↗

PubMed1994

Morphological adaptive changes of small intestinal tract regions due to pregnancy and lactation in rats.

In order to know the adaptive changes of small intestine regions (duodenum, and proximal, medial and distal jejunum-ileum) due to the reproductive stage (virgin, pregnancy and lactation), the weight, mucosal proportion, mucosal DNA and protein contents and protein/DNA ratio in female Wistar rats were measured. Pregnancy induces hypertrophy of the proximal half of the small intestine (duodenum and proximal jejunum-ileum), whereas lactation induces hyperplasia in all small intestinal regions and also hypertrophy but only in the duodenum.

Animals↗

PubMed1991

Effect of cafeteria diet on the gastrointestinal transit and emptying in the rat.

1. When gastrointestinal transit and emptying of intraluminal contents were studied using a radioactive tracer marker [( 14C]PEG-4000), the fastest gastric transit and the slowest overall transit time were observed in female Wistar rats (1-3 months old) after they were fed a cafeteria diet (a hypercaloric diet). 2. The small intestine length of cafeteria fed rats was higher than lean rats, whereas the stomach and large bowel length showed no difference between cafeteria and lean rats. 3. A state of mild obesity was obtained after rats were fed a cafeteria diet. This obesity was demonstrated by the highest body weight and the highest gain of white adipose tissue in rats fed a cafeteria diet.

Animals↗

PubMed1991

Gastrointestinal emptying in the final days of incubation of the chick embryo.

1. The gastrointestinal (GI) emptying of the chick embryo was studied in days 19 and 20 of incubation using radioactive (14C-PEG-4000) and coloured (Evans Blue dye) tracer markers. 2. Following administration by oral cannula, the percentages of tracer marker recovered in the yolk sac and the GI tract showed the existence of a GI motor pattern in both 19 d and 20 d chick embryos and suggested that the fluids drunk by the chick embryo during the final days of incubation could have reached the yolk sac from the GI tract via the vitelline diverticulum.

Animals↗

PubMed1989

Effect of glucocorticoids on gastrointestinal emptying in young broilers.

1. The rates of gastrointestinal (GI) emptying of 8- and 15-d-old chickens treated with 17-hydroxycorticosterone was measured using 14C-polyethylene glycol-4000. 2. The rate of progression of intraluminal contents along the GI tract was decreased by 17-hydroxycorticosterone in both 8- and 15-d-old chickens. Glucocorticoid treatment only delayed the rate of progression of intraluminal contents along the large intestine of the older birds. 3. Delayed transit of intraluminal contents could be explained by a precocious maturation of chick GI tract, induced by glucocorticoids. Loss of responsiveness to glucocorticoids occurs during the second week after hatching, except in the large intestine.

17-Hydroxycorticosteroids↗

PubMed1988

Developmental study of digestive motor response to dietary pattern in young broilers.

1. Gastrointestinal (GI) morphometry and motility were measured in young broilers (3, 8 and 15 days old) when they were submitted to three dietary patterns (ad libitum food, acute 48-hr fast and cumulative semi-starvation). 2. All GI regions were hypertrophied when acute or intermittent starvation were applied; lightly when acute starvation was applied and strongly with intermittent starvation. 3. All the 3-, 8- and 15-day-old acutely and intermittently starved chickens increased GI motility at the shortest times (0.5 and 1 hr) after the marker administration, but decreased GI motility at the longest times (2 and 4 hr). 4. The GI motor response of intermittently starved chicks was faster than the observed one in acutely starved chicks. The GI tract of intermittent starved chicks increased its motor response proportionally to the broilers age, while acutely starved chicks decreased their GI motility when the broilers age was increased. 5. A relationship between morphometrical and motor GI responses to dietary pattern has been inferred. From the gizzard and small bowel hypertrophy caused by intermittent starvation, an increased reflex GI motor response can be expected. Acute starvation only caused a light increase of GI motility, because it only increased the gizzard morphometry. 6. We concluded that young chicks respond to acute starvation by means of a short-term mechanism (an increase of GI motor reflexes) and responds to intermittent starvation by means of a medium- and long-term mechanism (a hypertrophy of GI tract and its subsequent increase of GI motor reflexes).

Age Factors↗

PubMed1986

Ontogeny of the gastrointestinal motility in young broilers.

Gastrointestinal motility of young broilers (1, 8 and 15 days old) was measured by means of 14C-polyethylene glycol-4000. Two motor patterns can be observed: GI segments anterior to ileum increased their motility proportionally to the broiler age. GI segments below ileum decreased their motility when the broiler age is increased. It is concluded that these motor patterns are due to immaturity of gastric motility, early learning of food intake regulation and/or interference between prenatal and postnatal nutrition. Proventriculus and duodenal loop showed to be transit segments, with independence of the broiler age.

Age Factors↗

PubMedDate not supplied

Effect of cafeteria diet on alpha-MG intestinal absorption in rats.

The effect of a cafeteria diet (a hypercaloric diet) on the accumulative ability of the mediated and non-mediated small intestine transport of alpha-methyl-D-glucoside (alpha-MG) in developing female Wistar rats was studied using everted intestinal slices. Cafeteria diet increased intestinal active transport and decreased intestinal passive diffusion of alpha-MG in 30-day-old rats. No differences in alpha-MG intestinal absorption were found in cafeteria vs control rats after the development of obesity in cafeteria diet fed rats. A link between gastrointestinal functions and the development of obesity induced by cafeteria diet is suggested.

Animals↗

PubMedDate not supplied

Effect of starvation on the in vivo intestinal absorption of sugars and amino acids in young chickens (Gallus domesticus).

The effect of different patterns of starvation (acute and intermittent) on the in vivo intestinal absorption of glucose and tryptophan during the first days of Gallus domesticus chicks life was measured. Both acute and intermittent starvation increase duodenal absorption of glucose and jejunal absorption of tryptophan. Intermittent starvation tends to reduce the effect of age which normally decreases intestinal uptake of nutrients. This effect is clearer for glucose absorption than for tryptophan absorption.

Animals↗