Bovine brain homogenate, fractionation

Fig. 1 Analysis by IFF In polyacrylamide gel (pH 3.5-10, 5% Amphollne, 3M urea) of the results of a fractionation of bovine brain homogenate with the Elphor VaP 21 operating In ZE mode. Sample supernatant of 300g of whole brain homogenized In 300 ml water, electrodlalyzed and centrifuged. Input at 3 ml/hr In the center channel (46). Buffer 10 mM sodium acetate, gH 5.0, 7 ml/ min. Electrophoresis conditions 218 V/cm, 85 mA, 6 C. The starting material Is In the left most lane (S). The fractions analyzed are shown In number. This Is a preliminary run and no optimization has been attempted. Hemoglobin and albumin from unremoved blood are Indicated.

U.L Lane 2 Bovine brain homogenate soluble fraction,... 

The highest PA-PLAi activity was observed in high speed supernatant fractions from homogenates of bovine testes and brain, with little or no activity in corresponding fractions from newborn testes, liver, spleen, heart, and blood [46]. A northern blot analysis of mRNA from human tissues agreed with the observations with bovine tissues [16]. 

This enzyme hydrolyzes the sulfate group from adenosine 5 -phosphosul-fate (APS) and is widely distributed in the animal kingdom (Bailey-Wood et al., 1969). Among various mammalian tissues, brain is the richest source. Intracellular distribution studies of APS sulfohydrolase have indicated a bi-modal distribution of this enzyme between lysosomal and cytosolic fractions of bovine liver and pig kidney (Bailey-Wood et al., 1970 Armstrong et al., 1970). Cytosolic APS sulfohydrolase has been purified to homogeneity from bovine liver (Stokes et al., 1973a). The purified enzyme has a molecular weight of 69,000 (Table 5). It has optimal activity at pH 5.4 (Table 6). 

Bovine chromaffin cells in primary culture possess carboxylcstcrase activities, 73% of w-hich is NTE the NTE component is resistant to inhibition by paraoxon and sensitive to mipafox and is localized to the particulate fraction of cell culture homogenates. Results suggest that bovine chromaffin cells may be a useful model for NTE studies because they possess a higher ratio of NTE/carboxylesterase than adrenal medulla tissue homogenates, brain tissue, or nerv e. 

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