1. © 2003 Science Press Internet Services FISIOLOGIA DIGESTIVA Clase 5: Secreción y digestión gástrica Dr. Michel Baró Aliste

2. © 2003 Science Press Internet Services Nutrients provided by animal and vegetable products

3. © 2003 Science Press Internet Services Digestive process is initiated by sensory signals

4. © 2003 Science Press Internet Services The effect of discussion, sight, and smell of food

5. © 2003 Science Press Internet Services Oral cavity has important functions in initial processing

6. © 2003 Science Press Internet Services

8. Secreción salival Estímulos gustativos (amargos) Tactiles (lisos)

9. © 2003 Science Press Internet Services Fases de la secreción gástrica Fase cefálica (30%) Fase gástrica (70%) -reflejos vago-vagales -reflejos entéricos locales -gastrina Fase intestinal Acetilcolinamoco Gastrinapepsinógeno HistaminaHCl

10. © 2003 Science Press Internet Services The arrival of a swallowed food bolus in the stomach (20-30% de la digestión total)

11. © 2003 Science Press Internet Services The emptying of food from the stomach

12. © 2003 Science Press Internet Services Passage of acidic, hyperosmolar gastric chyme into duodenum

13. © 2003 Science Press Internet Services Glándulas de la mucosa gástrica -80% oxínticas (cuerpo y fondo gástrico) -ácido clorhídrico -pepsinógeno I y II -factor intrínseco -moco -20% pilóricas -moco -pepsinógeno -gastrina Otras enzimas -lipasa gástrica (tributirasa) -amilasa gástrica -gelatinasa capa de moco protector 1mm rico en bicarbonato

14. © 2003 Science Press Internet Services

15. Célula parietal u oxíntica ( H+) = 160 mmol/L pH = 0,8 (H+)lum = 3.000.000 (H+)pl 1500 cal/L mitocondrias pepsinógeno (42500) pepsina (35000) activa a pH 1,8 a 3,5

16. © 2003 Science Press Internet Services Producción de ácido clorhídrico anhidrasa carbónica

17. © 2003 Science Press Internet Services Central nervous system: Regula células secretoras NMD del vago n. tracto solitario hipoglicemia aferentes del gusto y viscerales fondo antro fondo antro SSTR2= receptor somastostatina CCK-B= receptor CCK y gastrina pepsinógeno ácido clorhídrico mucus

18. © 2003 Science Press Internet Services The parietal cell

19. © 2003 Science Press Internet Services Stimulation of acid secretion

20. © 2003 Science Press Internet Services Peptides that affect gastric acid secretion

21. © 2003 Science Press Internet Services Gastrin effects on ECL cells are shown HDC: histidina decarboxilasa

22. © 2003 Science Press Internet Services Sources of gastric histamine

23. © 2003 Science Press Internet Services Interaction between histamine and other hormones Célula Parietal

24. © 2003 Science Press Internet Services Enterochromaffin-like (ECL) cell receptor

25. © 2003 Science Press Internet Services Histamine-producing (enterochromaffin-like) cell (a)

26. © 2003 Science Press Internet Services Histamine-producing (enterochromaffin-like) cell (b)

27. © 2003 Science Press Internet Services Gastrin: chronology of discoveries

28. © 2003 Science Press Internet Services Gastrin has multiple physiologic effects

29. © 2003 Science Press Internet Services Stimulations of gastrin release

30. © 2003 Science Press Internet Services Depressant factors of gastrin release

31. © 2003 Science Press Internet Services Human antral gastrin-producing (G) cell (a)

32. © 2003 Science Press Internet Services Human antral gastrin-producing (G) cell (b)

33. © 2003 Science Press Internet Services Human antral gastrin-producing (G) cell (c)

34. © 2003 Science Press Internet Services The G cell

35. © 2003 Science Press Internet Services Inhibition of gastrin release gastrina (+)

36. © 2003 Science Press Internet Services Chronology of gastrin-releasing peptide

37. © 2003 Science Press Internet Services GRP-releasing nerves in human gastric mucosa (a)

38. © 2003 Science Press Internet Services Gastrin-releasing nerves in human gastric mucosa (b)

39. © 2003 Science Press Internet Services Gastric distribution of gastrin-releasing peptide

40. © 2003 Science Press Internet Services Somatostatin chronology, chemistry, and localization

41. © 2003 Science Press Internet Services Human somatostatin-producing (D) cell (a)

42. © 2003 Science Press Internet Services Human somatostatin-producing (D) cell (b)

43. © 2003 Science Press Internet Services Human somatostatin-producing (D) cell (c)

44. © 2003 Science Press Internet Services Somatostatin functions and receptors

45. © 2003 Science Press Internet Services Combination that regulates gastric acid secretion

46. © 2003 Science Press Internet Services Digestión Gástrica

47. © 2003 Science Press Internet Services Carbohydrate is the major energy source in the diet + sucrosa lactosa %5 boca 30-40% En estómago (Maltosa) 50% Endoglucosidasa

48. © 2003 Science Press Internet Services Lipids have highest energy content of 3 macronutrients a-grasos esenciales: ac.linoleico ac.linolénico

49. © 2003 Science Press Internet Services The initial event in lipid digestion in the stomach Formación de gotas de emulsión Más relevante en el Período de lactante pH óptimo 4-5,5 Tributirasa: tributirina o grasa de la mantequilla Gotas de emulsión

50. © 2003 Science Press Internet Services Average daily protein intake is about 70-100 g in adults pH óptimo 2 – 3 Inactiva a pH 5 Digestión del colágeno de la carne Proteosas, peptonas, polipéptidos

51. © 2003 Science Press Internet Services Protein digestion begins in the stomach

52. © 2003 Science Press Internet Services Vitamin B12 is one of water-soluble vitamins (1 ug diario)

53. © 2003 Science Press Internet Services FIN