Results

Fetal rats aged 18 days prenatal :   

1) Control  group: All control subgroups  are the same 
-	By Haematoxylin and Eosin stain, the renal cortex of the fetal rat aged 18 days shows subcapsular zone containing the immature forms of renal developmental stages in the form of renal vesicle, comma shaped, S shaped bodies and immature glomerulus which appears as dense rounded structure.  The proximal tubules are lined by simple cuboidal epithelium with rounded, basal, vesicular nuclei. The distal tubules have a wide lumen and are lined by low cuboidal cells with central spherical nuclei (Figs. 1, 2).
-	 In Masson's Trichrome stain, the connective tissue is minimal in amount (Fig. 3). 

-	By E/M: The cells lining the proximal convoluted tubule have a single rounded nuclei. Its cytoplasm contains many mitochondria. These cells have many microvilli at its apical surfaces. Its lumen is obliterated by microvilli (Fig. 4). The cells lining the distal convoluted tubules showed few microvilli at its apical part. The cells have large nuclei occupying much more of the cell. The cytoplasm of these cells contains few mitochondria (Fig. 5). The glomerular filter consists of three components from inward to outward: fenesterated capillary endothelium, glomerular basal lamina and foot processes of podocytes (Fig. 6).

2) Experimental  group:

a-Lead acetate treated subgroup:
-	By Haematoxylin and Eosin stain, the proximal tubules are dilated and the lining epithelium is flattened with desquamation of cells in its lumen. Some distal tubules are degenerated. The glomeruli are intact (Fig. 7).
 - In Masson's Trichrome stain, the connective tissue is increased in amount   around the glomerulus and the tubules (Fig.8).

-	By E/M: The cells lining the proximal tubule show vacuolated mitochondria, their microvilli are few and the lumen is wide, the cells lining the distal tubules have small sized, shrinked nucleus, the cytoplasm shows multiple vacuoles.  The mitochondria are degenerated and in the form of clusters. The lumenal surface of these cells are irregular (Figs. 9 &10).
In comparison with control group, the glomerular filter show adhesions between the foot processes of podocytes.  The basal lamina show large area of thickening (Fig. 11).

b -  Lead acetate plus curcumin treated subgroup:
-	By Haematoxylin and Eosin stain, the lining epithelium of some proximal tubules is compressed with subsequent dilated lumen. Other proximal tubules are intact. some distal tubules show degeneration (Fig. 12).  
- In Masson's Trichrome stain, minimal amount of connective tissue is found around the glomerulus and the tubules (Fig.13). 

-	By E/M: Some cells lining the proximal tubules show shrinked nucleus and its cytoplasm has multiple vacuoles. The other cell appears intact with heterochromatic nucleus (Fig.14). Some cells lining the distal tubule show signs of degeneration in the form of vacuolated nucleus. Its cytoplasm is vacuolated and has degenerated mitochondria. Other cell has intact nucleus but vacuolated cytoplasm (Fig. 15). The glomerular filter has small areas of thickening in the basal lamina and the foot process are broad , thick and show adhesions between them (Fig. 16).

c-  Lead acetate plus vitamin C treated subgroup: 
-	By Haematoxylin and Eosin stain, the proximal tubules are intact, while other tubules show degeneration of its lining cells.  Some distal tubules show vacuolations in their cells (Fig.17).
-	  In Masson's Trichrome stain, minimal amount of connective tissue is seen around the glomerulus and the tubules (Fig. 18).

-	By E/M: The cell lining the proximal tubule shows normal nucleus. Its cytoplasm contains multiple vacuoles and intact mitochondria. The microvilli are intact and project in its lumen which obliterate it (Fig. 19). The cells lining the distal tubule show shrinked nucleus with indentation.  The cytoplasm is vacuolated. Some mitochondria are intact. The luminal border of these cells is irregular with scanty microvilli (Fig. 20). The glomerular filter show irregular thickening in the basal lamina and adhesions between the foot processes (Fig.21).

d- Lead acetate plus curcumin and vitamin C treated subgroup:
-	By Haematoxylin and Eosin stain the proximal tubule, the distal tubule and the glomerulus appear like normal (Fig. 22). 
-	 (Minimal amount of connective tissue is seen between the glomeruli and the tubule in Masson's Trichrome stain (Fig. 23).

-	By E/M: The cell lining the proximal tubule is cuboidal in shape. It has rounded nucleus and elongated mitochondria.  The microvilli are condensed and project in its lumen (Fig. 24). The cell lining the distal tubule has large nucleus, its cytoplasm show elongated intact mitochondria (Fig. 25). The glomerular filter consists of basal lamina with regular thickness and fenestrated endothelium, the foot process has slit pores between them (Fig. 26).  

Fetal rats aged 20  days prenatal :

1) Control subgroups: All control subgroups are the same 
-By Haematoxylin and Eosin stain, the renal cortex contains mature glomerulus with appearance of renal space, the proximal tubules consists of columnar cells with rounded basal nuclei (Fig. 27). 
- In Masson's Trichrome stain, there are minimal amount of connective tissue surround the glomeruli and the proximal and distal tubules (Fig. 28).

-	By E/M: The cells lining the proximal convoluted tubules have rounded nuclei with the cytoplasm have large number of elongated mitochondria. They show numerous microvilli at apical part of tubular cells, where the lumen is obliterated by these microvilli (Fig. 29). The cell lining the distal convoluted tubules has large nucleus, the mitochondria arranged in groups (Fig.30). The glomerular filter consisted of three components from inward to outward: fenesterated capillary endothelium, glomerular basal lamina with regular thickness, 1ry and 2ry foot processes of podocytes which have slit pores between them (Fig. 31).

2) Treated groups:

a- Lead acetate treated subgroup:
-	By Haematoxylin and Eosin stain, the glomerulus has a dilated renal space when compared with control group. Some proximal tubules are degenerated while other tubules show flattening of its lining cells and some cells are detached and accumulate in its lumen. Some distal tubules show degeneration (Fig. 32).
- In Masson's Trichrome stain, the connective tissue increased around the glomerulus and the tubules (Fig. 33).

-	By E/M: The cells lining the proximal convoluted tubules show multiple vacuoles of different sizes, lysosomes. Most of mitochondria are intact and few of them are degenerated. Its nucleus show indentations. The microvilli are still intact (Fig. 34). The cell lining the distal tubule has shrinked vacuolated nucleus and its cytoplasm show degenerated mitochondria and many vacuoles (Fig. 35). The glomerular filter show wide endothelial fenestrations and adhesions between the foot processes. There is   increase in the renal space (Fig. 36).

b -  Lead acetate plus curcumin treated subgroup: 
-	By Haematoxylin and Eosin stain, some glomeruli are degenerated with wide renal space, while the others are like normal. Degeneration of some proximal and distal tubules are seen while others like normal (Fig.37).
-	 In Masson's Trichrome stain, the connective tissue are increased around the glomeruli, the proximal and distal tubules (Fig. 38). 
-	By E/M: The cytoplasm of cells lining the proximal tubules contains multiple vacuoles, lysosomes and some degenerated mitochondria. Its nucleus is intact and basal. The microvilli obliterate the lumen of the tubules (Fig. 39). The cell lining the distal tubule has a nucleus with irregular outline and its cytoplasm contains few scattered mitochondria (Fig.40).The basal lamina of the glomerular filter show area of thickening, the renal space is increased and there are adhesions between the foot process (Fig. 41).

c-  Lead acetate plus vitamin C treated  subgroup: 
-	By Haematoxylin and Eosin stain, some proximal tubules are near normal but other tubules show degeneration of its lining cells.  Some distal tubules are degenerated (Fig. 42). 
-	In Masson's Trichrome stain there is decrease in the amount of connective tissue which surround the glomeruli and the tubules (Fig. 43). 
                                                                                              
-	By E/M:  The cytoplasm of cells lining the proximal tubules contain multiple vacuoles, lysosomes and elongated mitochondria, the microvilli are decreased (Fig. 44). The cell lining the distal tubule show degeneration of its nucleus which is large and pale. Some mitochondria are degenerated while others are intact (Fig. 45). The endothelial lining the glomerular filter shows areas of destructions and swollen, there are adhesions between the foot processes of podocytes (Fig.46). 

d- Lead acetate plus curcumin and vitamin C treated subgroup:
-	By Haematoxylin and Eosin stain, the proximal tubules appear intact.  Some glomeruli are intact and other has wide renal space (Fig. 47). 
-	In Masson's Trichrome stain, considerable amount of connective tissue are seen surrounding the glomeruli and the tubules (Fig.48).                                                        
-	By E/M:  The cells lining the proximal tubule have rounded nucleus and elongated mitochondria. The microvilli are intact and condensed in its lumen (Fig.49). The distal tubule is lined by cuboidal celles with large pale nucleus.  The cytoplasm contains few mitochondria (Fig.50). The glomerular filter show regular basal lamina, the primary and secondary process have slit pores (Fig.51).

Neonatal  rats at weaning (2weeks after birth):

1) Control subgroups:  All control subgroups are the same 
-	By Haematoxylin and Eosin stain, the mature glomeruli have parietal layer, visceral layer and renal space in between. The proximal tubule consists of columnar cells with rounded basal nuclei. The distal tubules have low cubical cells with wide lumen (Fig. 52). 
-	In Masson's Trichrome stain, the connective tissue is minimal in amount around the glomeruli and tubules (Fig. 53).

-	By E/M: The proximal tubules are lined with columnar cells which have large rounded nuclei, apical microvilli. The cytoplasm contains elongated mitochondria (Fig. 54). The cells lining the distal tubule have large oval nucleus. Its cytoplasm contains multiple groups of mitochondria. Its lumen has no microvilli (Fig. 55). The glomerular filter consists of fenesterated endothelium, basal lamina with regular thickness and the primary and secondary foot processes have slit pores between them (Fig. 56).
2) Treated groups:
a- Lead acetate treated  subgroup
-	By Haematoxylin and Eosin stain, the glomeruli are degenerated with wide renal space when compared with control group. The proximal and distal tubules are also degenerated (Fig .57). 
-	In Masson's Trichrome stain, there is condensed connective tissue around the glomerulus and the proximal and distal tubules (Fig. 58).

-	By E/M: The cells lining the proximal convoluted tubule show apical multiple vacuoles and cytoplasmic extension towards the lumen. The groups of mitochondria are intact (Fig.59). The cells of distal tubule have different sizes of nuclei and the cytoplasm contains large vacuoles, few mitochondria are degenerated while most of mitochondria are intact (Fig. 60). The glomerular filter show areas of thicknenig in the basal lamina and there are adhesions between the foot processes of podocyte (Fig. 61).

     b -  Lead acetate plus curcumin treated subgroup:
-	By Haematoxylin and Eosin stain, the glomeruli are degenerated with irregular parietal layer. Most of the proximal tubules are degenerated and vacuolated. Also, the distal tubules are degenerated (Fig. 62).
-	 In Masson's Trichrome stain, the amount of connective tissue is increased around the degenerated glomeruli and the proximal and distal tubules (Fig. 63).

-	By E/M: The proximal tubule is lined with columnar cells. Its cytoplasm shows multiple vacuoles. Most of the mitochondria   are intact (Fig. 64).  The cell lining the distal tubule shows pale apical nucleus. Its cytoplasm shows sowllen mitochondria (Fig.65). The glomerular filter show area of thicknenig in the basal lamina. There are adhesions between the foot processes of the podocytes (Fig.66).

c-  Lead acetate plus vitamin C treated subgroup:
-	By Haematoxylin and Eosin stain, some proximal tubules show degeneration and vacuolation of its lining cells, other tubules are intact. The glomeruli also show degeneration (Fig. 67).
-	 In Masson's Trichrome stain there are considerable amount of connective tissue around the glomerulus and the tubules (Fig.68).

-	By E/M: The proximal tubule is lined with columnar cells. Its cytoplasm shows apical vacuoles and many lysosomes. The microvilli are intact (Fig. 69). The cells lining the distal tubule show indentation of the nuclear membrane. The cytoplasm contains many vacuoles and some mitochondria are degenerated while other mitochondria are intact (Fig. 70). The glomerular filter shows area of thickness in the basal lamina (Fig. 71). 

d- Lead acetate plus curcumin and vitamin C treated subgroup:
-	By Haematoxylin and Eosin stain, the glomeruli are intact but its renal space is wide, the proximal and distal tubules appear like normal (Fig. 72).
-	In Masson's Trichrome stain, minimal amount of connective tissue lies between the tubules and around the glomerulus (Fig.73).

-	By E/M: The cells lining the proximal tubule are columnar with large oval nucleus. The cytoplasm contains elongated mitochondria and few vacuoles (Fig. 74). The cell lining the distal tubule has dark nucleus with central nucleolus, the cytoplasm has groups of intact mitochondria. There is apical extension of cytoplasm in the luminal cavity (Fig. 75). The glomerular filter show basal lamina with regular thickness, there are slit pores between the foot processes of the podocyte (Fig. 76).