Hema Tewari

In vivo and in vitro effects of cadmium on selected enzymes in different organs of the fish Barbus conchonius Ham. (rosy barb).

1. Enzyme modulation by cadmium in selected organs of the fish, Barbus conchonius (rosy barb), was investigated in vivo (48 hr exposure to 12.6 mg/l cadmium chloride) and in vitro (10(-6) M cadmium chloride). 2. The acetylcholinesterase (AchE) activity was depressed in the gills but stimulated in the skeletal muscles and brain in vivo. The hepatic, branchial, and renal acid phosphatase (AcP) activity decreased marginally in vivo but it was significantly increased in the gut and ovary. In vitro, except for the liver, the AcP activity was depressed in the selected organs. Collaterally, gut alkaline phosphatase (AlP) was significantly inhibited but a pronounced stimulation was noted in the kidneys and ovary in vivo. In vitro, the AlP activity was conspicuously elevated in the kidneys and gut, and moderately in the gills. 3. Cadmium inhibited the glutamate-oxaloacetate and glutamate-pyruvate transaminases (GOT and GPT) in the liver, gills and kidneys in vivo. In vitro, the GOT and GPT activities were decreased in the liver, gills and kidneys. The lactic dehydrogenase (LDH) was significantly stimulated by Cd in the heart in vivo but in vitro the metal inhibited the enzyme in the gills. 4. Enzymes in the liver, followed by those in the kidneys and gills seem to be most seriously affected by Cd poisoning in this fish.

Use of the fish enzyme system in monitoring water quality: Effects of mercury on tissue enzymes

1. Rosy barb (Puntius conchonius) were exposed to 181 micrograms/l mercuric chloride for 48 h and the activity of acid and alkaline phosphatases (AcP and AIP), aspartate aminotransferase (AAT), alanine aminotransferase (AIAT), lactic dehydrogenase (LDH), and acetylcholinesterase (AchE) were measured in vivo in several organs. 2. The AcP activity was inhibited in the liver, gills, kidneys, and gut but stimulated in the gonads. With the exception of kidney, the AIP activity showed an increase in all the organs examined. The AAT and AIAT were generally inhibited in different organs. An increase in LDH activity occurred in the cardiac and skeletal muscles while the AchE activity was considerably lowered in the brain, gills, and liver. 3. In vitro exposure to mercury at concentrations ranging between 10(-10) and 10(-4) M, inhibited the AIP, AAT, AIAT, LDH, and AchE activities in the tissues examined. The AcP activity was also depressed in all the tissues except in the testes, in which a marginal increase was noted. 4. The in vivo and in vitro effects of Hg were not of similar quality implying sequestration of toxic cations in the intact animals.

Effects of endosulfan on the blood and organ chemistry of freshwater fish, Barbus conchonius hamilton

Prolonged exposure (4 weeks) to 6.72 ppb of the organochlorine insecticide endosulfan induced disturbances in the blood and organ chemistry values of a common fish, Barbus conchonius. In blood the total lipids, cholesterol, and proteins were decreased in comparison to unexposed controls, while the free fatty acids (FFA), glucose, total phosphorus, and lactate were increased. Total lipids, FFA, and proteins were augmented in liver; cholesterol, in liver and ovary; and phosphorus and glycogen, in skeletal muscles. Compared to the controls, a decrease was seen in the total lipids (skeletal muscles and ovary), glycogen (liver, brain, and heart), and cholesterol (testes). Hyperlipemia, hyperproteinemia, and hyperlactemia persisted during a recovery period of 1 week in clean water following endosulfan poisoning.

Enzyme modulation by sublethal concentrations of aldicarb, phosphamidon, and endosulfan in fish tissues.

Abstract Enzyme modulation by acutely sublethal concentrations of aldicarb, phosphamidon, and endosulfan was examined in vivo and in vitro in different tissues of a fish, Puntius conchonius Ham. The AchE activity in brain and gills was decreased by three pesticides tested. In the skeletal muscles, while aldicarb and phosphamidon inhibited the enzyme, the endosulfan caused stimulation of AchE activity. The hepatic AcP was inhibited by aldicarb and phosphamidon but stimulated by endosulfan in vivo. In the gills, kidneys, and gut, however, the AcP activity was generally enhanced in vivo and decreased in vitro. Liver, gut, and ovaries showed inhibition of AIP with aldicarb and phosphamidon whereas the endosulfan induced both a reduction and a stimulation of the enzyme activity. Gills and kidneys revealed AlP stimulation with all three pesticides. The GOT was inhibited in the liver, gills, and kidneys but the activity was raised in the heart during pesticide exposure. In the liver, kidneys, and heart, the GPT activity was both increased and decreased during varying test conditions but the pesticides generally caused stimulation of this enzyme in the gills and skeletal muscles. The LDH activity was increased by aldicarb in the gills, skeletal muscles, and heart but inhibited in the liver. Phosphamidon and endosulfan induced inhibition of LDH activity in all the tissues except for an increase seen in heart muscles in vitro. With few exceptions, the in vivo and in vitro effects of pesticides on enzymes were qualitatively similar.

Sublethal effects of an organophosphorus insecticide on certain metabolite levels in a freshwater fish, Puntius conchonius Hamilton

Abstract Alterations in the metabolite levels were monitored in a common freshwater bony fish, Puntius conchonius, chronically exposed to a sublethal concentration (109.5 ppm) of an organophosphorus insecticide, phosphamidon. Significant hyperglycemia, hyperlactemia, hypercholesterolemia, hyperlipemia, hyperproteinemia, and increased blood-free fatty acids were manifested in the exposed fish for up to 4 weeks. The phosphorus levels in the blood, however, fell. In other tissues, there was an increase in the hepatosomatic index, moderate hepatic and skeletal muscle glycogenesis, a severe depletion of glycogen reserves in the brain, and a significant increase in heart glycogen. Cholesterol (liver, ovary, and testes), total lipids (liver and ovary), free fatty acids (liver and skeletal muscles), and total proteins (liver) were elevated in the exposed fish, and there were signs of lipolysis and protein breakdown in the skeletal muscles. Except for the liver-free fatty acids and heart glycogen, organophosphorus effects on other variables were not abolished during recovery in clean water.

Impact of chronic lead poisoning on the hematological and biochemical profiles of a fish,Barbus conchonius (Ham)

The contamination of natural waters by lead is mostly caused by a variety of anthropogenic activities related to increased mining operations and industrial uses of this metal. Adverse effects of lead poisoning in the fishes have been reported with references to both hematological and biochemical variables. The aim of present investigation was to study the effects of chronically administered sublethal levels of inorganic lead on the hematological and biochemical profiles of widely distributed freshwater fish, Barbus conchonius. The variables such as erythrocyte numbers, hemoglobin, hematocrit, mean corpuscular volume, blood glucose, glycogen in liver, skeletal muscles, and myocardium, and cholesterol in blood, liver, ovary, and testes were evaluated.

Short- and long-term effects of copper on the rosy barb (Puntius conchonius Ham.)

The rosy barb (Puntius conchonius) was exposed to copper (Cu) for short (48 hr) and long (8 weeks) terms and effects on enzyme activities and biochemical variables in the blood and tissues were examined. In vivo exposure to 571 micrograms CuSO4/liter (96-hr median tolerance limit (TLm)) for 48 hr stimulated to varying degrees acid phosphatase (AcP), alkaline phosphatase (AlP) (except in the liver), and acetylcholinesterase activities in selected tissues. The alanine aminotransferase and lactic dehydrogenase (LDH) (except in the heart) activities were inhibited to varying degrees in vivo. In vitro, the presence of 10(-6) M Cu suppressed enzyme activities in the tissues examined, with a few exceptions such as AcP in ovaries and gut, AlP in liver, gills, gut, and testes, and LDH in liver. Hyperglycemia, hyperlactemia, hyperproteinemia, elevated blood free fatty acid (FFA) levels, and hypocholesterolemia were manifested in the fish exposed to 190 micrograms CuSO4/liter (1/3 96-hr TLm). Effects on the tissues included glycogenolysis (liver and skeletal muscles), glycogenesis (brain and heart), a marked rise in hepatic proteins, accumulation of FFAs in liver and skeletal muscles, and reduction in hepatic and gonadal cholesterol contents. After 8 weeks, a trend toward recovery was noted in the biochemical variables (except blood and hepatic protein levels).

Cadmium nephropathy in a freshwater fish, Puntius conchonius hamilton

Renal pathology was examined in a freshwater fish, Puntius conchonius, during a 12-week exposure to 500, 630, and 840 micrograms CdCl2/liter (1/25, 1/20, and 1/15 fractions of the 96-hr TLm, respectively). Multifocal tubular epithelial degeneration including severe vacuolation and nuclear pyknosis and karyorrhexis composed the most obvious lesions. The degenerative changes were found mainly in the proximal segments, while the distal segments and the collecting tubules and ducts remained unaffected. Collapsed and shrunken glomeruli and swollen Bowmans spaces were also frequently observed. The cadmium-exposed fish appeared heavily stressed and moribund. A comparison of the renal pathology with that of other fishes and mammals and possible mechanisms of cadmium nephropathy are discussed.

Hepatopathotoxicity of three pesticides in a freshwater fish, puntius conchonius ham

Abstract Liver pathology was evaluated in a freshwater fish, Puntius conchonius, chronically exposed to sublethal concentrations of a carbamate, aldicarb (0.806 ppm), an organophosphorus, phosphami‐don (109.5 ppm), and an organochlorine, endosulfan (6.72 ppb). The hepatic lesions included hypertrophy, vacuolization, nuclear pycnosis and karyolysis, and fatty degeneration of hepatocytes. Focal necrotic changes were often noted in the treated fish. The carbamate proved to be more injurious to the liver as compared to the other two pesticides tested in this study.

Branchial pathogenesis in a freshwater fish, Puntius conchonius ham., chronically exposed to sublethal concentrations of cadmium

Effects of sublethal concentrations, 630 and 840 micrograms/liter (0.05 and 0.066 fractions of the 96-hr LC50), of cadmium chloride on the gills of a freshwater fish, Puntius conchonius, were examined light microscopically during a 12-week exposure. The secondary gill lamellae showed disrupted epithelium, necrosis, accumulation of cellular debris, capillary congestion, and wilting of the pillar cell system. Hypertrophy and hyperplasia of chloride cells as well as partial or complete fusion of secondary lamellae also occurred in the Cd-exposed fish. Branchial lesions together with coagulation film anoxia are likely to result in serious respiratory distress and related tissue hypoxia.