1. Digestive glands

2. General outline small digestive glands
distributed in the wall of digestive tract
esophageal glands, gastric glands and
intestine glands
large digestive glands
outside the wall of digestive tract
salivary glands, liver and pancreas

3. Large salivary glands Include parotid, submandibular and
sublingual glands
are compound tubuloacinar glands
are composed of acini and ducts

4. Large salivary glands

5. Acinus : acinar epithelium: simple cuboidal or pyramidal cells
myoepithelial cell
basal membrane
Structure:
Serous acini
Mucous acini
Mixed acini
Be divided into

7. Serous acini cytoplasma are deep stained
nucleus are spherical in shape and near
the base
secretion is thin, contains salivary amylase
and a little mucus

8. Serous acini and striated duct

9. Mucous acini cytoplasma are light-blue stained
nucleus are flattened ovoid shaped and
close to the base
secretion is thick; contains mucoprotein

10. Mucous acini

11. Mixed acini consist of above two kinds of cells
demilunes: several serous cells are
attached eccentrically to the mucous acini

12. Mixed acini

13. Ducts: Intercalated ducts diameter: thinnest
wall: simple low cuboidal epithelium

15. Striated duct (secretory duct)
wall: simple columnar epithelium; the nucleus
is near the cell apex; cytoplasm is
acidpphilic; has basal striations
EM: the basal striations created by
membrane infolding and mitochondia
reabsorbing sodium and excreting potassium;
transport water and ions

16. 导管(duct) 闰管：单扁或矮立方；短而细 单柱，胞质嗜酸性，核靠近细胞顶部 基底纵纹（EM：质膜内褶） 转运水和电解质（保钠排钾）
Intercalated duct
单柱，胞质嗜酸性，核靠近细胞顶部
基底纵纹（EM：质膜内褶）
转运水和电解质（保钠排钾）
纹状管
Striated duct
小叶间导管：假复柱
总导管：复扁

17. Intercalated ducts and striated ducts

18. Interlobular duct
Wall: pseudostratified epithelium
Main duct
Near its orifice become stratified
squamous epithelium

19. Parotid gland pure serous gland longer intercalated duct
secrete 25% of saliva, more salivary
amylase, less mucus

20. Parotid gland

21. Submandibular gland mixed gland. Serous acini are more than
mixed or mucous acini
short intercalated duct, longer striated duct
secrete 70% of saliva, less salivary amylase,
more mucus

22. Submandibular gland

23. Sublingual gland mixed gland, mucous and mixed acini
predominant, more demilune
without intercalated duct, obscure striated
duct
secrete 5% of saliva, most mucus

24. Sublingual gland

25. Pancreas Exocrine portion: the features of the acini
a single layer of pyramidal serous cells
surrounded by basal lamina, without
myoepithelial cells
centro-acinar cells: the epithelial cells of
intercalated duct penetrating into the
lumen of the acinus

26. the feature of ducts
the intercalated duct is long and has branches
no striated duct
main duct: lined by simple columnar
epithelium in which a few goblet cells
and endocrine cells can be seen

27. The functions of exocrine portion
Secret abundant trypsinogen,
chymotrypsinogen, amylase, lipase,
sodium bicarbonate and trypsin inhibitor

28. Pancreas

30. Pancreas ( show centro-acinar cells and intercalated ducts)

31. Endocrine portion (pancreatic islet):
rounded clusters of cells embedded within
exocrine pancreatic tissue
are divided into three kinds of cells: A, B,
and D cells
fenestrated capillaries are among the
cells

32. Pancreas (show pancreatic islet)

33. Endocrine portion PP cells: pancreatic polypeptide G cells: gastrin
Size
number
Distribution
Function
A cells
large
20%
Peripheral
glucagon
B cells
small
75%
center
insulin
D cells 5%
Among A and B cells
somatostatin
PP cells: pancreatic polypeptide
G cells: gastrin
Other cells

34. A cells
B cells
D cells

35. Liver Hepatic plates Sinusoid Central vein Liver lobule
Interlobular arteries
Interlobular veins
Interlobular bile ducts
Portal area

37. Functions of liver:
bile secretion
synthesize: protein, glycogen, cholesterin
detoxification and inactivation
defence
hemopoiesis

38. Human liver
Pork liver

39. Liver lobule: hepatic plates: are composed of a single
layer of hepatocytes arranged in radial
sinusoid: situated between the hepatic
plates, forming a complex network
central vein: occupies the centre of the
liver lobule

40. Liver lobule

42. Hepatic plates

43. Hepatic cords and liver sinusoids

44. Hepatocytes polyhedral in shape, eosinophilic cytoplasm,
one or two large rounded nuclei with one or 2
typical nucleoli
EM: Mi, RER, SER, Golgi apparatus,
lysosomes, microbodies, inclusions

45. Mitochondria
provide the energy for the hepatocytes
Rough endoplasmic reticulum
synthesize some plasma proteins
Golgi apparatus
participate in the formation of bile and lipoprotein

46. Smooth endoplasmic reticulum
synthesize bile, triglyceride and LDL
metabolism of the lipid, hormones and
cholerythrin
inactivate steroid hormone
biotransformation of some materials
detoxification of noxious substances

47. Lysosomes
actively participate the metabolism of
hepatocyte and renewal of organelles
play a role in metabolism and transport of
cholerythrin
storage of iron

48. Microbodies
detoxification: catalase and peroxidase;
reduce the hydrogen peroxide into H2O
Inclusions
include glycogen, lipid droplets, pigment etc;
These contents vary according to physiologic state of human body

49. Bile canaliculi between two adjacent hepatocytes
the membrane of hepatocyte projects to
the lumen, forming many microvilli
the cell membranes near the bile canaliculi
are firmly bound by junctional complexes

50. Bile canaliculi

51. Liver sinusoid spaces between the hepatic plates irregular in shape
composed of only one discontinuous layer of
fenestrated endothelial cells, no diaphragm,
no basement membrane
Kupffer cells are located within the sinusoid
cavities

52. 肝血窦 Hepatic sinusoid 分布：位于肝板之间 内皮不连续，有孔无隔膜，吞饮小 泡，无基膜 结构： 功能：
通透性大，有利于肝细胞与血液间
物质交换
枯否细胞
窦周隙： 贮脂细胞、网状纤维
（Disse 隙）

53. Kuffer cells in liver sinusoid

54. Liver sinusoid and space of Disse

55. Space of Disse separates the endothelium from the hepatocytes
contains some reticular fibers and fat-storing
cells

57. 肝细胞超微结构

58. Portal space: the connective tissue separating the lobules including
Interlobular arteries
Interlobular veins
Interlobular bile ducts

59. Portal spaces

60. Blood circulation: portal V. interlobular V. sinusoids central V.
（functional vessel)
sinusoids
central V.
hepatic A.
interlobular A.
sublobular V.
(nutrient vessel)
hepatic V.

61. 肝的血液循环：
门V 小叶间V
肝血窦 中央V 小叶下V
肝A 小叶间A 肝V
下腔V

62. Blood vessels of liver
(prepared Chinese ink injection through portal vein)

63. Discharge way of bile: Bile canaliculi Hering’s canals
Interlobular bile ducts
Gallbladder
Hepatic duct
Common bile duct
Cystic duct
duodenum

64. 胆汗排出途径：
肝细胞
胆小管 闰管
小叶间胆管
左、右肝管
胆总管
十二指肠
胆囊管 胆囊

65. Gallbladder Simple columnar Epi. , no Goblet cells
Laminar propria: C.T.
mucosa
muscle layer: composed of an inner circular,
an outer longitudinal layers of smooth muscle
adventitia: most are fibrosa, some are serosa

66. Gallbladder

67. 肝细胞超微结构及其相关功能： Mi：供能 RER：合成蛋白质（白蛋白、纤维蛋白原、酶） SER：合成、转运胆汁；糖、脂、类固醇激素
代谢；解毒
Golgi：加工运输蛋白质、分泌胆汁
lysosome ：自噬、异噬、胆红素转运、储存铁
微体：解毒

68. 复习思考： 简答
胰岛外分泌部，胰岛，肝血窦，窦周隙
胆小管，肝细胞邻接面 问答
联系超微结构说明肝细胞的功能