1. Lab 2 Connective tissue (I)
Jun Zhou(周俊）, Ph.D & M.D
School of Medicine,Zhejiang University

2. Connective tissue （part 1)
1.Spread slide (No. 4) (Drawing)
2.Loose CT (No.1) (small intestine)
3.Dense CT ( No.14) (finger skin)
4.Adipose tissue (No.14/No.6)
5.Reticular tissue (No.6) (lymph node)

3. Classification Connective tissue proper:
Loose connective tissue
Dense connective tissue
Adipose tissue
Reticular tissue
Specialized connective tissue:
Cartilage
Bone
Blood

4. Characteristics Fewer cells, more matrix, more cell types
No polarization
Numerous blood vessles
From mesoderm-mesenchyme

5. Loose connective tissue
macrophage
fibroblast
The mesentery of rabbit.
Injected some biological granules into the abdominal cavity, so that macrophage can display obvious phagocytotic activity, e.g.,visible ingested material within their cytoplasm.
No.4 Spread slide H&E × 400
Collagenous fiber, Elastic fiber, Fibroblast, Macrophage

6. Loose connective tissue
Elastic fiber
macrophage
Collagenous fiber

7. Loose connective tissue
submucosa
Loose connective tissue in the submucosa of small intestine.
No.1 Small intestine: H&E × 40

8. Submucosa of small intestine: H&E × 400
Fibroblast
Collagenous fiber
Fibroblasts in connective tissue.
Photomicrograph of a connective tissue specimen in a routin H&E-stained,paraffin-embedded preparation shows nuclei in inactive fibroblasts-fibrocyte.
Submucosa of small intestine: H&E × 400

9. Small intestine: H&E × 400
Refracted elastic fiber

10. Dense connective tissue
dermis
Dense connective tissue is composed of thick collagen bundles and stain deeply with eosin. It has relatively few cells, most of which are fiboblasts. Usually elastic fibers are visible only with special staining methods.
No.14 Skin: DCT H&E × 40

11. E.F
C.F
fibroblast
Skin: DCT H&E × 400

12. Skin: DCT H&E × 400

13. Adipose tissue
Adipose tissue
No.6 Lymph node: HE X40

14. Lymph node: Adipose tissue H&E × 400
Adipocyte differentiate from undifferentiated mesenchymal cells and gradually accumulate fat in their cytoplasm. When adipocytes accumulate in large numbers, they are called adipose tissue.
Lymph node: Adipose tissue H&E × 400

15. Reticular tissue
No.6 Lymph node: Reticular tissue HE X400

16. Lymph node: Reticular tissue Silver X100

17. Lymph node: Reticular tissue Silver X400

18. Fibroblast Macrophage
During the repair process of a wound, the activated fibroblasts exhibit more basophilic cytoplasm. which is readily observed with the light microscope.

19. Mast cell
Mast cells stained by H.& E., The granules stain intensely and ,because of their numbers, tend to appear as a solid mass in some areas. The nucleus of the cell is represented by the pale-staining area.

20. Plasma cell
The photomicrograph shows the typical features of plasa cells as seen in a routine H&E preparation. Note clumps of peripheral heterochromatin alternating with clear euchromatin in the nucleus. Also note the negative Golgi and basophilic cytoplasm.

21. Collagenous fibers collagenous fibril
Electron micrograph of collagen fibers. The thread like collagen fibrils are aggregated in some areas to form relatively thick bundles, in other areas, the fibrils are more dispersed.
A longitudinal section collagen fibril from the left specimen seen at higher magnification. Note the banding pattern repeat every 68 nm along the length of the fibril.
Collagenous fibers
collagenous fibril

22. fibroblast Plasma cell macrophage Mast cell Electron micrograph.
Fibroblast: RER and Golgi apparatus. Have several processes.
Plasma cell: extensive RER occupies most of the cytoplasm of the plasma cell. The Golgi apparatus is also relatively large, a further refection of the cell’s secretory activity.
Mast cell: the cytoplasm of a mast cell that is virtually filled with granules
Macrophage: The most distinctive feature of the macrophage is its population of endocytotic vesicles, early and late endosomes, lysosomes, and phagolysosomes.The surface of the cell reveals a number of fingerlike projections, some of which may be sections of surface folds.
macrophage

23. THE END!