We analyzed the activities of acetylcholinesterase and butyrylcholinesterase, and of the metabolic enzymes enolase and lactate dehydrogenase, in the superior cervical ganglion, ciliary ganglion, dorsal root ganglion, stellate ganglion, and caudate nucleus of the cat; we found that these tissues possess very different levels of enzymic activities. The proportions of the aa, ay, and yy enolase isozymes are also quite variable. We particularly studied the molecular forms of acetylcholinesterase and butyrylcholinesterase, in normal tissues and in preganglionically denervated SCG, in comparison with earlier histochemical fimdings. The results are consistent with the premise that the G, (globular monomer) forms of both enzymes are located in the cytoplasm, the G4 (globular tetramer) forms are at the plasma membranes, and the A12 (collagen-tailed, asymmetric dodecamer) form of acetylcholinesterase is at synaptic sites.Acetylcholinesterase (EC 3.1.1.7; AcChoEase) and butyrylcholinesterase (EC 3.1.1.8; BtChoEase) have been shown to exist in a number of molecular forms, particularly the globular monomer (G1), dimer (G2), and tetramer (G4) and the collagen-tailed (or asymmetric) A4, A8, and A12 forms (1). In the superior cervical ganglion of the rat (2) and steer (3) the G1, G4, and A12 forms predominate. There is evidence (1) to suggest that the G1 form is associated with the cytoplasm or endoplasmic reticulum, the probable site of synthesis (4); the G4 form is probably located at cellular membranes, and the A12 form, by analogy with the motor endplate of skeletal muscle (5), at synaptic sites.Since the distributions ofAcChoEase and BtChoEase have been studied extensively in the nervous tissue of the cat by light (6)(7)(8) and electron (9-11) microscopic histochemistry, this species appears to be ideal for correlation of biochemical and anatomical data. In this study, we describe the distributions of the molecular forms of AcChoEase and BtChoEase, determined by sucrose gradient sedimentation, in normal and preganglionically denervated superior cervical ganglion (SCG) and in normal ciliary ganglion (CG), dorsal root ganglion (DRG), stellate ganglion (StG), and caudate nucleus (CN). We also compare the levels of AcChoEase and BtChoEase with those of the metabolic enzymes lactate dehydrogenase (LDH) and enolase. Neurons produce a specific type of enolase subunit (y), while glial cells produce only the ubiquitous subunit (a) (12). These subunits form dimers, so that three different isozymes are found in the nervous tissue (13).
METHODSFor determination of LDH and enolase activity, the tissues were extracted in 50 mM imidazole HCI buffer, pH 6.8/4 mM MgSO4/40 mM KCl. The supernatant obtained (50,000 x g, 30 min) was assayed for LDH activity with 20 mM (do-lactic acid and 10 mM NAD, in 10 mM Tris-HCI buffer (pH 8). The reaction was monitored at 340 nm. The total enolase activity was assayed by the method of Rider and Taylor (14), and the proportions of aa, ay, and yy isozymes were determined by DEAE-cellulose chromatogr...