Ontogeny of rat gastric H+-K+-ATPase activity
Autor: | Robert Ducroc, F. Hervatin, E. Moreau, P. Millet, P. Avril, J. P. Geloso, B. Garzon |
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Rok vydání: | 1987 |
Předmět: |
Male
Aging medicine.medical_specialty Physiology ATPase Weaning Biology H(+)-K(+)-Exchanging ATPase chemistry.chemical_compound Fetus Physiology (medical) Internal medicine medicine Animals Incubation Omeprazole Parietal cell Adenosine Triphosphatases chemistry.chemical_classification Hepatology Stomach Gastroenterology Rats Inbred Strains Enzyme assay Rats medicine.anatomical_structure Endocrinology Enzyme Animals Newborn chemistry Gastric Mucosa biology.protein Gastric acid Female Histamine Subcellular Fractions medicine.drug |
Zdroj: | American Journal of Physiology-Gastrointestinal and Liver Physiology. 252:G28-G32 |
ISSN: | 1522-1547 0193-1857 |
DOI: | 10.1152/ajpgi.1987.252.1.g28 |
Popis: | Gastric H+-K+-ATPase activity was examined in subcellular fractions (P1, 1,000 g; P2, 20,000 g; P3, 100,000 g) obtained from fundic mucosae of fetal, newborn, and adult rats. Depending on the tissue secretory state the distribution of this enzyme activity predominates in P3, i.e., resting adult, or in P2, i.e., stimulated adult, while total enzyme activity (P2 + P3) remains constant. Enzyme activity was detected as soon as day 19 of gestation and P2 + P3 reached 2.2 +/- 0.2 mumol Pi X mg prot-1 X h-1 at parturition. H+-K+-ATPase activity steadily decreased from 4.0 +/- 0.7 mumol Pi X mg prot-1 X h-1 on day 6 after birth to approximately 0 on day 12. This activity recovered as soon as day 13 (3.5 +/- 0.6 mumol Pi X mg prot-1 X h-1) and continued to rise slowly until adulthood. Incubation of subcellular fractions with 0.1 mM omeprazole resulted in a total loss of H+-K+-ATPase activity at all the stages of development examined. These studies of functional relationship during the development between gastric acid secretion and distribution of gastric H+-K+-ATPase activity among P2 and P3 fractions indicate that this last could be considered as an index of the secretory state of the parietal cell. This enzyme's pattern of development in P2 + P3, correlated with the one previously observed for stimulated H+ secretion in intact tissue, suggest that the H+-K+-ATPase is the limiting step in response to secretagogues during postnatal period. |
Databáze: | OpenAIRE |
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