In continuation of previous reports, it was found that the neurotrophic factor (NF) of the central nervous system of the cat for the maintenance of acetylcholinesterase (acetylcholine acetylhydrolase, EC 3.1.1.7; AcChoEase) in the denervated cat superior cervical ganglion is a heat-stable compound of low molecular weight (<1,000) and that it is probably a peptide. Acetylcholine and nerve growth factor were eliminated as the NF; cyclic AMP produced an effect similar to that of the NF. The NF is probably not present in significant amounts in liver or skeletal muscle; it appears to be present in small intestine. It does not modify the AcChoEase content of the nondenervated cat superior cervical ganglion. Possible mechanisms of action of the NF are discussed.We have shown that arterial infusion for 24 hr of an extract of the brain, spinal cord, and sciatic nerves of cats prevents almost completely the fall in the acetylcholinesterase (acetylcholine acetylhydrolase, EC 3.1.1.7; AcChoEase) and butyrylcholinesterase (acylcholine acylhydrolase, EC 3.1.1.8; BtChoEase) contents of the cat superior cervical ganglion (SCG) that otherwise results 48 hr after preganglionic denervation (1). It was shown subsequently that ligation of the external carotid (EC) and lingual (L) arteries is necessary to obtain the full effect of the extract and to counteract partially a similar but lesser effect produced by continual anesthesia with sodium pentobarbital; although the effect was demonstrable when the infusion time was reduced to 6 hr, it was much less marked and consistent than with 24-hr infusion (2). The compound(s) responsible for the preservation of ganglionic AcChoEase and BtChoEase was designated a neurotrophic factor (NF).The present report describes studies addressed to characterization of the NF by 24-hr infusions of authentic agents and of dialyzed and enzyme-treated preparations of the central nervous system (CNS)/sciatic nerve extract. METHODSPreparation of the infusion extract (extract of the brain, spinal cord, and sciatic nerves of cats), anesthetic and surgical procedures, and methods for homogenization of ganglia, for determination of ganglionic AcChoEase, BtChoEase, and protein contents, and for calculation of statistical significance of mean differences were identical with those reported previously (1). Under sodium pentobarbital anesthesia (35 mg/kg of body weight i.p.), 1 cm was resected from both cervical sympathetic trunks; the wound was sutured, and Combiotic (penicillin and dihydrostreptomycin, Pfizer; 0.5 ml) was given i.m. The following day cats were anesthetized as before and treated with atropine (1.0 mg/kg i.p.); artificial respiration was administered through a tracheal catheter attached to a Palmer pump, and a slow i.v. infusion of 5% glucose/0.45% NaCl was started. Heparin at 50 units/kg was given i.v. just prior to bilateral ligation of the EC and L arteries and was repeated every 6 hr. Infusion of the solution under test was begun -24 hr after denervation and continued until the time of sac...

The effects of selective inactivation of propionylcholinesterase (PrChE) by tetramonoisopropylpyrophosphortetramide (iso-OMPA) on the steady state and regenerating levels of acetylcholinesterase (AChE) were investigated on the superior cervical ganglion (SCG) of the rat. Over the dosage range of 1.5-40.0 pmol iso-OMPA/kg intraperitoneally, which produced nearly total inactivation of ganglionic PrChE and 0-35% inactivation of AChE, there was no subsequent increase in AChE activity above the control level. Single or repeated injections of iso-OMPA at total doses of 5.0-40.0 pmol/kg intraperitoneally caused no reduction in the rate of regeneration of ganglionic AChE during the 24 h following its inactivation by sarin, 2.0 pmol/kg intravenously. Both sets of findings differ from those obtained previously in a similar study of ganglionic AChE and butyrylcholinesterase (BuChE) in the cat. Possible reasons for this distinct species difference are discussed. Neurocyt. 7, 145-154.KLINGMAN G. I. & KLINGMAN J. D. (1969) Cholinesterases of rat sympathetic ganglia after immunosympathectomy, decentralization and axotomy. J. Neurochem. 16, KOELLE G. B. (1954) The histochemical localization of cholinesterases in the central nervous system of the rat. J. comp. Neurol. 100, 211-228. KOELLE G. B. (1955) The histochemical identification of acetylcholinesterase in cholinergic, adrenergic and sensory neurons. Refinement of the bis-(thioacetoxy) aurate (I) method for 605-615. 78, 785-809. m c . 7, 88-95. 261-268.

When homogenates of cat or rat superior cervical ganglia in Krebs-Ringer solution were incubated at 370C, the ensuing decrease in acetylcholinesterase (acetylcholine acylhydrolase, EC 3.1.1.7) activity was increased significantly K prior administration in vivo of tetramonoisopropylpyroPiosphotetramide at doses that produced selective al ylphosphorylation of butyrylcholinesterase or propionylcholinesterase. These findings are consistent with the proposal that the latter enzymes are posttranscriptional precursors of acetylcholinesterase. Results of similar studies with homogenates of ganglia in water or in M NaCl/1% Triton X-100 were inconclusive, as were those of heat-inactivation studies and immunoprecipitation of the enzymes.It has been proposed that butyryleholinesterase (BuChoE; acylcholine acylhydrolase, EC 3.1.1.8) may function as a posttranscriptional precursor of acetylcholinesterase (AcChoE; acetylcholine hydrolase, EC 3.1.1.7) at postsynaptic membranes in the superior cervical ganglion (SCG) of the cat and elsewhere (1), on the basis of the electron microscopic demonstration of the identical localizations of AcChoE and BuChoE at that site (2) and the finding that after its inactivation by sarin the rate of regeneration of AcChoE in the SCG and other autonomic ganglia of the cat was decreased significantly by the persistent selective alkylphosphorylation of BuChoE by tetramonoisopropylpyrophosphotetramide (iso-OMPA) (3). An attempt to extend the latter observation to the rat was unsuccessful (4). In this species, the nonspecific ChoE is a propionylcholinesterase (PrChoE; EC 3.1.1.8) (5) and its cytological localization in the SCG differs considerably from that in the cat (6). Vigny and associates (7) peritoneally at 2-3 hr prior. Stellate ganglia (StG) and SCG were excised from cats; SCG were excised from rats. The ganglia were trimmed, weighed, and frozen until they were homogenized within the succeeding few hours. All experiments with rat ganglia were performed with batches of 10 pairs, which had an aggregate weight of approximately 20 mg.Homogenates for use in the heat-inactivation, immunoprecipitation, and initial incubation studies were prepared in a medium identical with that described by Vigny et al. (7), consisting of 1% Triton X-100 (TrX), 1 M NaCl, 5 mM ethylene glycol bis(f3-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), and 0.01 M Tris-HCl, final pH 7.0, (NaCl/TrX) without or with the subsequent addition of 0.05 M MgCl2. The frozen SCG and StG from cats were scissor-minced, transferred quantitatively to chilled homogenizing tubes, and homogenized in an ice-water bath with a Tissumizer SDT-100N (Tekmar) at maximal speed for a total of 3 min with fractional addition of medium, according to a fixed schedule, to a final concentration of 10.0 mg of wet tissue per ml. The homogenates were strained through two layers of wide-mesh gauze (type VII, Johnson & Johnson) into hand-homogenizing tubes, frozen, and stored at -20°C until use on the same or the following day. Homogenates of poo...

No abstract

Experiments were designed to test the hypothesis that ganglionic butyrylcholinesterase (BuChE) is derived from acetylcholinesterase (AChE). At 5 to 8 days following preganglionic denervation of the right superior cervical ganglion (SCG), cats were given sarin, 2.0 mumol/kg, i.v. At intervals of 1 h and 1, 2, 3, 6, 11, and 22 days later, they were killed, and the AChE and BuChE contents of both SCG and both stellate ganglia (StG) were assayed. The regeneration of AChE in the normal ganglia occurred in two phases: an initial rapid phase, to 25-40% of control activity in 1 day, and a slow phase, to approximately 70% of control activity in 22 days. BuChE reached approximately 85% of control activity in normal SCG and StG at 22 days. In the denervated SCG, AChE activity reached a maximum of approximately 17% of normal at 1 day, the value prior to the administration of sarin, and did not increase appreciably above this subsequently. BuChE activity in the denervated SCG reached approximately 50% of normal ganglia at 22 days. At each interval, its activity approached 55% of that of the contralateral normal SCG, the value found in the denervated SCG prior to the administration of sarin. Hence, the regeneration of BuChE appears to be independent of the presence of AChE in the neuropil. The origin of ganglionic BuChE remains obscure.