To detect distribution and relative frequency of diffuse neuroendocrine system （DNES） cells in the gastrointestinal tract of channel catfish （lctalurus punctatus）, the intestinal tract of channel catfish was divid...To detect distribution and relative frequency of diffuse neuroendocrine system （DNES） cells in the gastrointestinal tract of channel catfish （lctalurus punctatus）, the intestinal tract of channel catfish was divided into seven portions from proximal to distal： the enlarged area after oesophagus, cardia, fundus, pylorus, and anterior, middle, and posterior intestine. Immunohistochemical method using the strept avidin-biotin-complex （SABC） was employed. All antisera between seven portions of the channel catfish were compared statistically using statistical package for the social science （SPSS）. Five types of DNES ceils were determined： neuropeptide Y-immunoreactive （NPY-IR） cells were demonstrated in both anterior and middle intestine; serotonin （5-HT） immunoreactive cells were detected throughout the whole gastrointestinal tract; vasoactive intestinal peptide （VIP） positive cells were at the highest frequency in pylorus; glucagon-immunoreactive （GLU-IR） cells were moderate in number in the fundus and anterior, middle intestine, and no immunoreactivity was determined in the other portions; somatostatin （SOM） positive cells were more abundant in the anterior and middle intestine. The regional distribution and relative frequency of immunoreactive cells in the channel catfish, Ictalurus punctatus, are essentially similar to those of other fish. However, some characteristics are observed in this species, which further proved that the diversity of the physiological function of DNES cells was based on their morphology.展开更多
The channel catfish Ictalurus punctatus was first introduced from the United States to the Krasnodar region of Russia 1972-1979, and it was introduced into Georgia during 1976-1978. Ecological and economic studies of ...The channel catfish Ictalurus punctatus was first introduced from the United States to the Krasnodar region of Russia 1972-1979, and it was introduced into Georgia during 1976-1978. Ecological and economic studies of channel catfish were initiated along with the acclimatization and naturalization of this new species. Channel catfish were initially reproduced and reared in the Japan aquaculture fish farm ponds. Offspring from these ponds were used to stock other ponds, industrial fish farms and natural water bodies （lakes） where natural populations were formed. The climatic conditions of Georgia are close to the natural habitat of channel catfish. The number of days with water temperature higher than 20 ℃ is about 120-140, and the accumulated heat reaches up to 2,400-2,792℃. The purpose of targeted acclimatization was for the development of aquaculture-commercial production and recreational fisheries. During the process the method of staged radial acclimatization was applied, which initially included breeding and growing of fishes in aquaculture farms. Offspring produced in hatchery were then introduced into new fish farms and water bodies to develop populations. The water temperature 22-26 ℃ in the ponds are suboptimal for breeding the channel catfish, nevertheless the productivity in ponds is 3 tons/ha, in cages 50-60 kg/m3, and in pools with thermo-regulation of water 100-150 kg/m3. In some trial water bodies, the natural breeding of channel catfishes were observed, proving the existence of independent （self-breeding） populations. This process however was significantly hampered by severe economical hardship occurred in the country during 1990＇s joined with the uncontrolled fishery. The current economical growth in the country also influences the aquaculture sector and many private fish farmers are interested in commercial breeding of channel catfish, scarce population of which still exists in the former experimental water bodies. The bio-technology of rearing the channel catfish, elaborated during the 1980s, is part of the aquaculture curricula in the universities.展开更多
The objectives of this study were as follows: 1) to establish a baseline ethoxyresorufin-O-deethylase (EROD) activity level in channel catfish (Ictalurus punctatus), 2) to assess changes in induction of cytochrome P45...The objectives of this study were as follows: 1) to establish a baseline ethoxyresorufin-O-deethylase (EROD) activity level in channel catfish (Ictalurus punctatus), 2) to assess changes in induction of cytochrome P450 enzyme in channel catfish following exposure to creek water at the discharge point from the Troy (Alabama) Wastewater Treatment Plant (TWWTP) compared to upstream samples from Walnut Creek, 3) to compare EROD activity in populations maintained in laboratory and field settings, and 4) to quantify cytochrome P450 gene expression. Enzyme activity was measured fluorometrically and CYP1 gene expression was analyzed by quantitative real-time reverse transcription polymerase chain reaction. A mean EROD baseline was established at 0.03 nmol/min/μg of protein. The overall mean field effluent (TF) EROD had a significant 5-fold increase over field upstream (UF) exposed catfish;and overall mean laboratory effluent (TL) exposed catfish EROD had a significant 1.8-fold increase over laboratory upstream (UL) exposed catfish. Field exposures generally showed more robust enzyme induction over laboratory exposures on all sampling days. Ex- pression of the CYP1B gene following TF exposure was 6-fold over UF. Results suggested that in situ exposure to wastewater pollutants using caged test organisms provided a much more sensitive local monitor of pollutant exposure and biological impact than ex situ toxicological studies.展开更多
PBDEs are widely used brominated flame retardant, which are increasingly reported in the environment. Concentrations of thirteen PBDEs in a large number of channel catfish and fish feeds collected from Hubei province ...PBDEs are widely used brominated flame retardant, which are increasingly reported in the environment. Concentrations of thirteen PBDEs in a large number of channel catfish and fish feeds collected from Hubei province of China were investigated in this study. A fast isotopic dilution GC-MS method was firstly developed to simultaneously determine thirteen PBDEs in channel catfish and fish feeds in this study, and especially for the first time PBDEs in fish feeds. Pressurized liquid extraction and multi-layer silica gel column chromatography cleanup were used, some important steps and crucial parameters were modified and intensified compared with other literatures, and GC and MS conditions were optimized. The limits of quantitation values of 0.25 - 5 μg·kg-1 wet weight in channel catfish were calculated for PBDEs;so did 1 - 20 μg·kg-1 wet weight in fish feeds. In addition, good repeatability and accuracy of the whole method were achieved. The established methods were therefore suitable for the simultaneous determinations of thirteen PBDEs in these samples at trace contamination levels. Using the established methods, PBDEs emerged in 10 of 180 channel catfish and 13 of 115 fish feeds, and the dominant PBDEs homologues were PBDE-28, PBDE-47, PBDE-100, PBDE-99, PBDE-154, PBDE-153 and PBDE-183. The detection rates of seven PBDEs congeners were in turn respectively 1.74%, 7.83%, 4.35%, 5.22%, 3.48%, 2.61% and 2.61% in fish feeds, and detection rates of seven PBDEs congeners were in turn respectively 1.11%, 3.89%, 2.22%, 1.67%, 1.11%, 1.11% and 1.11% in channel catfish. There was significant correlation in PBDEs between matching channel catfish and fish feeds (R2 = 0.742, P < 0.001, n = 30), suggesting that fish feeds contaminated with PBDEs possibly resulted in PBDEs residual in channel catfish through biological transfer.展开更多
以7 mg/L的孔雀石绿浸泡斑点叉尾苗种5min后将其饲养于池塘的网箱中,研究了在养殖模式下孔雀石绿及其代谢物隐色孔雀石绿在斑点叉尾苗种各组织中的分布及消除规律。采用高效液相色谱串联质谱法(HPLC-MS/MS)分析孔雀石绿及其代谢物...以7 mg/L的孔雀石绿浸泡斑点叉尾苗种5min后将其饲养于池塘的网箱中,研究了在养殖模式下孔雀石绿及其代谢物隐色孔雀石绿在斑点叉尾苗种各组织中的分布及消除规律。采用高效液相色谱串联质谱法(HPLC-MS/MS)分析孔雀石绿及其代谢物隐色孔雀石绿在斑点叉尾血液、肌肉、皮肤、肝脏、肾脏组织中的浓度水平。采用药代动力学分析软件3p97对血药浓度时间数据进行分析。结果表明,孔雀石绿和隐色孔雀石绿血药浓度时间曲线符合有吸收二室模型,动力学方程分别为:C孔雀石绿=683.063 e 0.248 t+11.176e 0.006 t 694.239e 0.333 t,C隐色孔雀石绿=757.240 e 0.222 t+14.474 e 0.007 t–771.714 e 0.382 t。血液中孔雀石绿和隐色孔雀石绿达峰时间Tpeak分别为3.480和3.623h,峰浓度值Cmax分别为81.560和159.619 ng/mL,表观分布容积Vd/F分别为37.689和21.125 L/kg,分布相的一级速率常数α分别为0.248和0.222/h,消除相的一级速率常数β分别为0.006和0.007/h,吸收半衰期T(1/2)α分别为2.794和3.124h,消除半衰期T(1/2)β分别为113.068和105.841h,中央室向周边室转运的一级速率常数K12分别为0.020和0.015/h,周边室向中央室转运的一级速率常数K21分别为0.159和0.121/h,药-时曲线下面积AUC分别为2493.944和3601.863 ng.h/mL。肌肉、皮肤、肝脏和肾脏组织中孔雀石绿和隐色孔雀石绿浓度水平的结果表明,孔雀石绿在斑点叉尾4种组织中浓度由高到低的顺序是皮肤>肌肉>肾脏>肝脏,其中斑点叉尾皮肤组织易蓄积孔雀石绿,其残留时间最长,肝脏组织由于对孔雀石绿有极强的代谢转化功能而浓度较低。孔雀石绿在肌肉、皮肤、肝脏和肾脏组织中的消除方程分别为C=5.570 e 0.009t、C=6.302 e 0.007t、C=4.791 e 0.006t和C=4.591 e 0.002t,相关系数r2≥0.773,消除半衰期T1/2肌肉、皮肤、肝脏和肾脏分别为3.2、4.1、4.8和14.4d。肌肉、皮肤、肝脏和肾脏组织中孔雀石绿分别在45、60、30和60d才未被检测到;隐色孔雀石绿在斑点叉尾4种组织中浓度由高到低的顺序是肝脏>皮肤>肌肉>肾脏,残留时间最长的组织也是皮肤组织。隐色孔雀石绿在肌肉、皮肤、肝脏和肾脏组织中的消除方程分别为C=6.491 e 0.004t、C=6.958 e 0.003t、C=6.722 e 0.007t和C=6.162 e 0.002t,相关系数r2≥0.673,消除半衰期T1/2肌肉、皮肤、肝脏和肾脏分别为7.2、9.6、4.1和14.4d。肌肉、皮肤、肝脏和肾脏组织中隐色孔雀石绿分别在90、90、60和90d才未被检出。试验期间(2011年5月17日至7月15日)平均水温为26.4℃,孔雀石绿和隐色孔雀石绿90d后在各组织中才未检测到,因此,使用7 mg/L孔雀石绿浸泡2龄斑点叉尾苗种孔雀石绿及其代谢物隐色孔雀石绿至少应经过2376℃.d后才能消除。展开更多
基金supported by the Special Founda-tion for Young Leaders Fellowship in the Sichuan Agri-cultural University, China (45078925-5).
文摘To detect distribution and relative frequency of diffuse neuroendocrine system （DNES） cells in the gastrointestinal tract of channel catfish （lctalurus punctatus）, the intestinal tract of channel catfish was divided into seven portions from proximal to distal： the enlarged area after oesophagus, cardia, fundus, pylorus, and anterior, middle, and posterior intestine. Immunohistochemical method using the strept avidin-biotin-complex （SABC） was employed. All antisera between seven portions of the channel catfish were compared statistically using statistical package for the social science （SPSS）. Five types of DNES ceils were determined： neuropeptide Y-immunoreactive （NPY-IR） cells were demonstrated in both anterior and middle intestine; serotonin （5-HT） immunoreactive cells were detected throughout the whole gastrointestinal tract; vasoactive intestinal peptide （VIP） positive cells were at the highest frequency in pylorus; glucagon-immunoreactive （GLU-IR） cells were moderate in number in the fundus and anterior, middle intestine, and no immunoreactivity was determined in the other portions; somatostatin （SOM） positive cells were more abundant in the anterior and middle intestine. The regional distribution and relative frequency of immunoreactive cells in the channel catfish, Ictalurus punctatus, are essentially similar to those of other fish. However, some characteristics are observed in this species, which further proved that the diversity of the physiological function of DNES cells was based on their morphology.
文摘The channel catfish Ictalurus punctatus was first introduced from the United States to the Krasnodar region of Russia 1972-1979, and it was introduced into Georgia during 1976-1978. Ecological and economic studies of channel catfish were initiated along with the acclimatization and naturalization of this new species. Channel catfish were initially reproduced and reared in the Japan aquaculture fish farm ponds. Offspring from these ponds were used to stock other ponds, industrial fish farms and natural water bodies （lakes） where natural populations were formed. The climatic conditions of Georgia are close to the natural habitat of channel catfish. The number of days with water temperature higher than 20 ℃ is about 120-140, and the accumulated heat reaches up to 2,400-2,792℃. The purpose of targeted acclimatization was for the development of aquaculture-commercial production and recreational fisheries. During the process the method of staged radial acclimatization was applied, which initially included breeding and growing of fishes in aquaculture farms. Offspring produced in hatchery were then introduced into new fish farms and water bodies to develop populations. The water temperature 22-26 ℃ in the ponds are suboptimal for breeding the channel catfish, nevertheless the productivity in ponds is 3 tons/ha, in cages 50-60 kg/m3, and in pools with thermo-regulation of water 100-150 kg/m3. In some trial water bodies, the natural breeding of channel catfishes were observed, proving the existence of independent （self-breeding） populations. This process however was significantly hampered by severe economical hardship occurred in the country during 1990＇s joined with the uncontrolled fishery. The current economical growth in the country also influences the aquaculture sector and many private fish farmers are interested in commercial breeding of channel catfish, scarce population of which still exists in the former experimental water bodies. The bio-technology of rearing the channel catfish, elaborated during the 1980s, is part of the aquaculture curricula in the universities.
文摘The objectives of this study were as follows: 1) to establish a baseline ethoxyresorufin-O-deethylase (EROD) activity level in channel catfish (Ictalurus punctatus), 2) to assess changes in induction of cytochrome P450 enzyme in channel catfish following exposure to creek water at the discharge point from the Troy (Alabama) Wastewater Treatment Plant (TWWTP) compared to upstream samples from Walnut Creek, 3) to compare EROD activity in populations maintained in laboratory and field settings, and 4) to quantify cytochrome P450 gene expression. Enzyme activity was measured fluorometrically and CYP1 gene expression was analyzed by quantitative real-time reverse transcription polymerase chain reaction. A mean EROD baseline was established at 0.03 nmol/min/μg of protein. The overall mean field effluent (TF) EROD had a significant 5-fold increase over field upstream (UF) exposed catfish;and overall mean laboratory effluent (TL) exposed catfish EROD had a significant 1.8-fold increase over laboratory upstream (UL) exposed catfish. Field exposures generally showed more robust enzyme induction over laboratory exposures on all sampling days. Ex- pression of the CYP1B gene following TF exposure was 6-fold over UF. Results suggested that in situ exposure to wastewater pollutants using caged test organisms provided a much more sensitive local monitor of pollutant exposure and biological impact than ex situ toxicological studies.
文摘PBDEs are widely used brominated flame retardant, which are increasingly reported in the environment. Concentrations of thirteen PBDEs in a large number of channel catfish and fish feeds collected from Hubei province of China were investigated in this study. A fast isotopic dilution GC-MS method was firstly developed to simultaneously determine thirteen PBDEs in channel catfish and fish feeds in this study, and especially for the first time PBDEs in fish feeds. Pressurized liquid extraction and multi-layer silica gel column chromatography cleanup were used, some important steps and crucial parameters were modified and intensified compared with other literatures, and GC and MS conditions were optimized. The limits of quantitation values of 0.25 - 5 μg·kg-1 wet weight in channel catfish were calculated for PBDEs;so did 1 - 20 μg·kg-1 wet weight in fish feeds. In addition, good repeatability and accuracy of the whole method were achieved. The established methods were therefore suitable for the simultaneous determinations of thirteen PBDEs in these samples at trace contamination levels. Using the established methods, PBDEs emerged in 10 of 180 channel catfish and 13 of 115 fish feeds, and the dominant PBDEs homologues were PBDE-28, PBDE-47, PBDE-100, PBDE-99, PBDE-154, PBDE-153 and PBDE-183. The detection rates of seven PBDEs congeners were in turn respectively 1.74%, 7.83%, 4.35%, 5.22%, 3.48%, 2.61% and 2.61% in fish feeds, and detection rates of seven PBDEs congeners were in turn respectively 1.11%, 3.89%, 2.22%, 1.67%, 1.11%, 1.11% and 1.11% in channel catfish. There was significant correlation in PBDEs between matching channel catfish and fish feeds (R2 = 0.742, P < 0.001, n = 30), suggesting that fish feeds contaminated with PBDEs possibly resulted in PBDEs residual in channel catfish through biological transfer.
文摘以7 mg/L的孔雀石绿浸泡斑点叉尾苗种5min后将其饲养于池塘的网箱中,研究了在养殖模式下孔雀石绿及其代谢物隐色孔雀石绿在斑点叉尾苗种各组织中的分布及消除规律。采用高效液相色谱串联质谱法(HPLC-MS/MS)分析孔雀石绿及其代谢物隐色孔雀石绿在斑点叉尾血液、肌肉、皮肤、肝脏、肾脏组织中的浓度水平。采用药代动力学分析软件3p97对血药浓度时间数据进行分析。结果表明,孔雀石绿和隐色孔雀石绿血药浓度时间曲线符合有吸收二室模型,动力学方程分别为:C孔雀石绿=683.063 e 0.248 t+11.176e 0.006 t 694.239e 0.333 t,C隐色孔雀石绿=757.240 e 0.222 t+14.474 e 0.007 t–771.714 e 0.382 t。血液中孔雀石绿和隐色孔雀石绿达峰时间Tpeak分别为3.480和3.623h,峰浓度值Cmax分别为81.560和159.619 ng/mL,表观分布容积Vd/F分别为37.689和21.125 L/kg,分布相的一级速率常数α分别为0.248和0.222/h,消除相的一级速率常数β分别为0.006和0.007/h,吸收半衰期T(1/2)α分别为2.794和3.124h,消除半衰期T(1/2)β分别为113.068和105.841h,中央室向周边室转运的一级速率常数K12分别为0.020和0.015/h,周边室向中央室转运的一级速率常数K21分别为0.159和0.121/h,药-时曲线下面积AUC分别为2493.944和3601.863 ng.h/mL。肌肉、皮肤、肝脏和肾脏组织中孔雀石绿和隐色孔雀石绿浓度水平的结果表明,孔雀石绿在斑点叉尾4种组织中浓度由高到低的顺序是皮肤>肌肉>肾脏>肝脏,其中斑点叉尾皮肤组织易蓄积孔雀石绿,其残留时间最长,肝脏组织由于对孔雀石绿有极强的代谢转化功能而浓度较低。孔雀石绿在肌肉、皮肤、肝脏和肾脏组织中的消除方程分别为C=5.570 e 0.009t、C=6.302 e 0.007t、C=4.791 e 0.006t和C=4.591 e 0.002t,相关系数r2≥0.773,消除半衰期T1/2肌肉、皮肤、肝脏和肾脏分别为3.2、4.1、4.8和14.4d。肌肉、皮肤、肝脏和肾脏组织中孔雀石绿分别在45、60、30和60d才未被检测到;隐色孔雀石绿在斑点叉尾4种组织中浓度由高到低的顺序是肝脏>皮肤>肌肉>肾脏,残留时间最长的组织也是皮肤组织。隐色孔雀石绿在肌肉、皮肤、肝脏和肾脏组织中的消除方程分别为C=6.491 e 0.004t、C=6.958 e 0.003t、C=6.722 e 0.007t和C=6.162 e 0.002t,相关系数r2≥0.673,消除半衰期T1/2肌肉、皮肤、肝脏和肾脏分别为7.2、9.6、4.1和14.4d。肌肉、皮肤、肝脏和肾脏组织中隐色孔雀石绿分别在90、90、60和90d才未被检出。试验期间(2011年5月17日至7月15日)平均水温为26.4℃,孔雀石绿和隐色孔雀石绿90d后在各组织中才未检测到,因此,使用7 mg/L孔雀石绿浸泡2龄斑点叉尾苗种孔雀石绿及其代谢物隐色孔雀石绿至少应经过2376℃.d后才能消除。
