Shark dogfish

Evans, D.H., K.E. Weingarten, and J.S. Walton. 1990. The effect of atropine on cadmium- and nickel-induced constriction of vascular smooth muscle of the dogfish shark ventral aorta. Toxicology 62 89-94. 

There is a large variation in tissue distribution of PCBs among different fish species. In coho salmon and rainbow trout liver contains a low concentration of PCB and a low percentage of the total amount of PCB in the fish (33,34). On the other hand, in spot and dogfish shark liver contains the highest concentration and percentage (5,28). 

The main organ involved in PCB metabolism and excretion in fish is the liver. Metabolism of PCBs in fish liver homogenates has been demonstrated (29,30,32) and PCB metabolites are excreted into bile (25,28,34). What is not known is extent to which PCB metabolites excreted in bile are eliminated in feces. Also the role of kidneys, gills, intestine and skin in PCB elimination in fish has not been fully elucidated. The only study on urinary excretion of PCBs was in dogfish sharks and revealed that urine was not a major route of elimination (28). 

Xenobiotic Transport Mechanisms and Pharmacokinetics in the Dogfish Shark... 

Figure 2. Technique for collection of bile via fistula in the dogfish shark...

Figure 3. Time course of tissue and plasma concentrations of phenol red model predictions vs. experimental results. The lines are model predictions the symbols are experimental data for iv injection of 10 mg/kg into the caudal vein of dogfish sharks. Each symbol represents the average of five to eight female sharks/time point with SD indicated by vertical bars. The limit of sensitivity of the assay was 25,15, and 5 g/g or mL for ( ), kidney (K) Liver (L) and (O), plasma (P),...

For the purpose of the following discussion, the xenobiotics studied in the dogfish shark were divided into three classes 1) those relatively hydrophilic (Table V) those relatively lipophilic (i.e., solubility in water less than 1 mg/ml, Table VI) and, 3) metal-containing pollutants (Table VII) Most of these data have been previously reported (18-23) using C compound, for assay, with the exception of sodium lauryl sulfate (SLS) ( S), cis-Pt (atomic absorption spectroscopy) and phenol red (spectrophotometry). Unless otherwise stated these data are presented as total radioactivity and the hazards of doing so are recognized (24). 

In the present compilation of the distribution and pharmacokinetic data of a dozen xenobiotics studied in the dogfish shark, this species yielded excellent data consistent with what we know from similar studies on terrestrial mammals. The data from the shark occasionaly provided information not available in other animals. Major transport parameters in this fish were shown to be similar to those found in mammals. This aquatic organism handles lipid-soluble pollutants by sequestering them in its fatty liver. Together with a previous summary (23) we have now studied about three dozen xenobiotics in this species. Because of its ease of handling, low cost, abundance, predictive value of transport mechanisms, and well-developed pharmacokinetics, the dogfish shark is an ideal fish species to use as a model to study aquatic pollutants. 

Trodusquemine (221) (isolated from the liver of the dogfish shark, Squalus acanthias) Sulfated aminosterol Trodusquemine (MSI-1436) (221) Diabetes Suppresses mammalian appetite through inhibition of protein tyrosine phosphatase IB (PTP-IB) Phase I (against type 2 diabetes and related symptoms) Genaera Corporation 974-978... 

Rao MN, Shinnar AE, Noecker LA, Chao TL, Feibush B, Snyder B, Sharkansky I, Sarkahian A, Zhang X, Jones SR, Kinney WA, Zasloff M. (2000) Aminosterols from the dogfish shark squalus acanthias. J Nat Prod 63 631-635. 

O Q Bilirubin Dogfish shark, Squalus acanthias Bile 32... 

To summarize, several studies have demonstrated the ln iortance of conjugation reactions in determining the fate of xenobiotics in aquatic am mala. Among fish, most Information had been gained in the trout, the southern flounder, the winter flounder and the dogfish shark. It is evident that there are considerable Interspecles differences in the ability of fish to conjugate xenobiotics, as is true for other species, but the major pathways of conjugation are similar in all animal species studied. 

C. Steroidal amine from the Dogfish Shark Squalus acanthias. 249... 

A novel unsaturated polyaminosteroidal sulfate, squalamine (44), was isolated from tissues of the dogfish shark Squalus acanthias. Squalamine (49) is found to be a 3/3-JV-l-iV[3-(4-aminobutyl)] l,3-diaminopropane-7a,24(R)-... 

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