Infrared Radiation Influence on Molt and Regeneration of Neohelice granulata Dana, 1851 (Grapsidae, Sesarminae)

Abstract

This paper analyzes the influence of infrared radiation (IR) on regeneration, after autotomy of limb buds of Neohelice granulata and consequently the time molt. Eyestalks were ablated to synchronize the start of molt. Afterward, animals were autotomized of five pereopods and divided into control and irradiated groups. The irradiated group was treated for 30 min daily until molt. Limb buds from five animals of days 4, 16 and 20 were collected and histological sections were made from them. These sections were photographed and chitin and epithelium content measured. Another group was made, and after 15 days limb buds were extracted to analyze mitochondrial enzymatic activity from complex I and II. The irradiated group showed a significant reduction in molt time (19.38+/-1.22 days) compared with the control group (32.69+/-1.57 days) and also a significant increase in mitochondrial complex I (388.9+/-27.94%) and II (175.63+/-7.66%) in the irradiated group when compared with the control group (100+/-17.90; 100+/-7.82, respectively). However, these effects were not accompanied by histological alterations in relation to chitin and epithelium. This way, it was possible to demonstrate that IR increases complex I and II activity, reduces the time molt and consequently increases the appendage regeneration rate.

Histopathological Analysis of UVB and IR Interaction in Rat Skin

“…Animals had their whole body irradiated inside polypropylene boxes similar to those used for maintenance for 15 days and were sacrificed on the 16th day. Irradiation times were determined in previous experiments by our group and co‐workers . To account for the biological differences between crabs and rats, a small initial test group was irradiated with different times of IR and UVB.…”