Alarm cells and their distribution in different regions of Barbus sharpeyi's skin

Abstract

Skin of 20 normal, mature and same size fish (27.27±3.33cm) were subjected to microscopic assessment in different regions including lip, pectoral fin, head, back, side (on lateral line) and abdomen. The skin sections were prepared using routine paraffin embedding and stained by H&E and PAS. The alarm cells distribution were counted in 100 µ length of epidermis. Microscopic results showed that voluminous cells existed in the middle to deeper layers of non-keratinization stratified squamous epidermis in all regions except for lip. These cells contained large and achromatic nucleus in the center of cytoplasm. The cytoplasm has negative reaction to PAS staining. Histo-metrical results showed that shape and number of these cells vary in different regions of skin, with the differences being significant in all regions except for the back, abdomen and pectoral fin skin (P<0.05). Based on the distribution of alarm cells, we could divide the epidermis into four regions: I - The skin of lip region carrying no alarm cells. 2- The skin of head region with 14.814±0.304 alarm cells in I length of epidermis. 3- The skin of dorsal and ventral regions and pectoral fin containing 27.628±1.167, 28.228 .54 and 29.629±0.314 alarm cells in 100 µ length of epidermis respectively. 4- The skin of lateral region with 47.4971±0.512 alarm cells in 100µ length of epidermis.