The ameliorating effect of oral ascorbic acid (AA) was evaluated against changes in sperm parameters in New Zealand White (NZW) rabbits treated with endosulfan. Rabbits (6 to 8 months old) were divided into four groups of six animals each. Rabbits in TRT-I served as control and received corn oil by oral gavage for 6 weeks. Rabbits in TRT-II received endosulfan (1 mg/kg bw per day) in corn oil. TRT-III group received oral corn oil daily and ascorbic acid (AA; 20 mg/kg bw) every other day for 6 weeks. TRT-IV group received the same amounts of endosulfan and AA. Endosulfan alone significantly reduced the sperm count and motility and increased the presence of sperm with morphologic problems. AA treatment showed significant amelioration when coupled with endosulfan. Ameliorations were up to control levels in all cases except for sperm motility. The data suggested that AA has beneficial influences in neutralizing the toxic effects of endosulfan in the spermatologic parameters of NZW males.

We investigated the endosulfan-induced alterations and the effect of vitamin C supplementation on endosulfan-induced alterations in serum biochemical markers of oxidative stress and antioxidant capacity in rabbits. Basal, 4th and 6th week serum levels of total oxidant status (TOS), thiobarbituric acid reactive substances (TBARS), advanced oxidation protein products (AOPP), total antioxidant capacity (TAC), total protein sulfhydryl (T-SH) and glutathione-S-transferase (GST) were measured in rabbits administered endosulfan (1 mg/kg) alone or in combination with vitamin C (20 mg/kg) for 6 weeks. Control rabbits received either vehicles or vitamin C. Serum TOS, TBARS and AOPP levels at 4th and 6th week were significantly higher whereas T-SH levels were significantly lower than basal values in endosulfan-administered rabbits. GST increased significantly at 4th week but decreased below basal value at 6th week. Similarly, TAC decreased significantly at 6th week. Vitamin C supplementation increased TAC at 4th and 6th weeks in controls and increased T-SH and GST and decreased TOS, TBARS and AOPP at 4th week in endosulfan-administered rabbits. TAC increased significantly at 6th week by vitamin C supplementation in endosulfan-administered rabbits. There were significant increments in TBARS and decrements in TAC and GST levels at 6th week compared to 4th week in endosulfan-administered rabbits. Present findings indicated to an increased and progressively uncompensated oxidant stress in endosulfan-administered rabbits that was substantially ameliorated by vitamin C supplementation through an improvement in antioxidant capacity. It was suggested that vitamin C supplementation might be helpful in preventing the detrimental effects of increased oxidative stress caused by endosulfan exposure.

The present study was conducted using 6 to 8 month old New Zealand white male rabbits (nine rabbits per treatment group). Daily gavages of 3, 1.5, 0.75, or 0 mg endosulfan/kg BW in corn oil resulted in the death of five (55%), three (33%), zero (0%), and zero (0%) rabbits, respectively, in 30 days. All rabbits were monitored for any observable toxic symptoms throughout the experimental period (30 d) and they also were weighed weekly to monitor body weight gain. All deaths occurred within the first 3 weeks and nervous symptoms were observed only for a few minutes before death. Alterations recorded in hematological parameters within the groups (hemoglobin, packed cell volume, and total erythrocyte count) were due to endosulfan exposure. Serum alkaline phosphatase (ALP) and aspartate aminotransferase (AST) levels were significantly elevated in the 3 mg/kg dose group. Gross post-mortem and histopathological changes in various organs (lung, liver, kidney, and testes) of rabbits treated with endosulfan were observed with typical organochlorine dose-dependent signs of toxicity. Although some animals appeared to adjust to relatively high daily doses of endosulfan for 30 days, biochemical and histological evidence indicated varied liver and kidney damage relative to dosage administered to these animals. The current subacute (30 day) study suggested a NOAEL of 0.75 mg endosulfan/kg in New Zealand white rabbits.

Çalışmamızda endosülfan uygulaması yapılan erkek Yeni Zellanda tavşanlarında C vitamini (VitC) ilavesinin bazı kan ve biyokimyasal parametreler ile oksidan-antioksidan denge üzerine düzeltici etkisinin araştırılması amaçlanmıştır. Bu amaçla, yaşları 6 ile 8 ay arasında değişen 24 tavşan, her grupta 6 tavşan olacak şekilde, rastgele 4 çalışma grubuna ayrıldı. Kontrol grubundaki tavşanlara (TRT-I) mısır yağı verildi. İkinci grupta bulunan tavşanlara (TRT-II) günlük 1 mg/kg endosülfan mısır yağında eritilerek verildi. Üçüncü gruptaki tavşanlara 20 mg/kg dozunda VitC gün aşırı olarak uygulandı (TRT-III). Son gruptaki tavşanlara (TRT-IV) aynı oranlarda endosülfan ve VitC verildi. Oral yolla yapılan bu uygulamalar 6 hafta boyunca devam etti. Çalışmamızda toplam eritrosit ve trombosit, hemoglobin, hematokrit, ve lökosit değerleri yönünden gruplar arasında fark gözlenmezken, toplam lökosit sayılarında anlamlı bir fark bulundu. Ayrıca serum glukoz, alanin aminotransferaz (ALT), malondialdehit (MDA), glukoz 6 fosfat dehidrojenaz (G6PD), glutatyon peroksidaz (GPx) ve eritrosit katalaz (CAT) aktivitelerinde de farklılık tespit edilmedi. TRT-III grubunda serum VitC seviyesi yükselirken, TRT-II grubunda serum alkalen fosfataz (ALP) ve aspartat aminotransferaz (AST) seviyeleri arttı. Bununla birlikte VitC uygulamasının TRT-IV grubundaki tavşanlarda ALP ve AST seviyelerini TRT-II grubuna göre azalttığı gözlendi. Elde edilen bulgulara göre, VitC uygulamasının endosülfanın bazı zararlı etkilerine karşı erkek Yeni Zellanda tavşanlarında koruyucu olabileceği sonucuna varıldı. Anahtar kelimeler: kan parametreleri, biyokimyasal parametreler, oksidan-antioksidan denge, endosülfan toksikasyonu, insektisit kullanımı, Vitamin C