17 TESTICULAR HISTOPATHOLOGICAL CHARACTERISTICS OF RAMS TREATED WITH LOW-LEVEL LASER THERAPY: PRELIMINARY RESULTS

Abstract

Testicular degeneration is caused by the loss of testicular thermoregulation induced by high environmental temperature, reproductive disruptions, fever, and others processes. Low-level laser therapy (LLLT) is an important tool to induce cellular proliferation and to stimulate mitosis. This biostimulatory effect was observed in the seminiferous epithelium of rats treated with LLLT, obtaining better results using a cumulative dose of 28.05 J cm–2 rather than 46.80 J cm–2 (Taha and Valojerdi 2004 Lasers Surg. Med. 34, 352–359). Thus, the aim of this study was to evaluate the effect of different LLLT protocols on testes histopathological characteristics of rams submitted to scrotal insulation for the induction of the testicular degeneration. For this, 6 rams were divided in 3 groups: (1) control, without LLLT treatment (n = 2); (2) LLLT treatment with a cumulative dose of 28 J cm–2 (n = 2); and (3) LLLT treatment with a cumulative dose of 56 J cm–2 (n = 2). Treatment was performed once a day and repeated every 48 h during a 15-day interval in the treated groups (2 and 3). The output power used was the same for the treated groups (30 mW). Scrotal insulation was done in all rams at 72 h before the beginning of the treatment period. The rams were castrated after 35 days of scrotal insulation. Both testes were divided in 3 parts: ventral, medium, and dorsal. The testes segments were fixed using Bouin fluid and stained using hematoxylin-eosin. Analyses were performed by light microscopy (model 80i; Nikon, Tokyo, Japan) using the NIS-Elements AR® to measure the lumen of the seminiferous tubules and the seminiferous tubules total area. Ten different areas of each testicular segment were analysed and, in each area, 2 seminiferous tubules were chosen randomly. For this analysis, the percentage of the lumen area of the seminiferous tubule in relation to the total area of the seminiferous tubule (lumen/lumen + tubule) was determined. In parallel, degree of degeneration was classified by blind analysis, as light, moderate, or severe, in each testicular segment. The data was analysed employing SAS (SAS Institute Inc., Cary, NC, USA). The treatment effect was tested using PROC GLM (ANOVA). Tukey's test was used to compare the averages. A treatment effect (P < 0.001) was observed. Group 2 (14.55 ± 2.08%) presented a lower percentage of lumen than did group 1 (36.78 ± 3%) and 3 (30.98 ± 2.24%). The degeneration degree of ram testes of group 1 was classified as moderate for 1 ram and severe for the other, whereas, in group 2, it was classified as light for both rams. For group 3, it was classified as moderate for both rams. Thus, it is possible to conclude that LLLT treatment is efficient, and that the cumulative dose of 28 J cm–2 is more efficient than the cumulative dose of 56 Jcm–2, a corroboration of previous results in rats (Ibid.). However, the results are preliminary and more studies are being done by our group. The authors acknowledge FAPESP processes 2012/00040-0 and 2011/16744-3.