The release of acetylcholine elicited by extracts of black widow spider glands: studies using rat superior cervical ganglia and inhibitors of electrically stimulated release.

An extract of the venom glands of black widow spiders (BWGE) induces the release of acetylcholine (ACh) from the superior cervical ganglia of rats. The release of ACh follows first-order kinetics, which suggests that the venom either lowers the ganglionic store of ACh, or continually reduces the rate of release. Since ganglionic ACh did not decrease in the presence of BWGE, it is likely that the venom continually reduces the rate of release. The rate constant for BWGE-induced release of ACh is depressed about 45% by treatment of the ganglion with either botulinum toxin or a low Ca++/high Mg++Ringer's solution. The rate constant is depressed about 30% by treatment of the ganglion with 8.3 microng/ml of cytochalasin-B. Since these agents inhibit the release of ACh which is elicited by electrical stimulation of the ganglion, it is suggested that one action of BWGE is the stimulation of some step in the physiological mechanism involved in the release of neurotransmitters. Treatment of the ganglion with tetrodotoxin had no effect on the rate constant for release induced by BWGE. The action of BWGE on the ganglion was not reversible after 10 minutes. When treated with BWGE, ganglia whose stores of transmitter had been labeled by electrical stimulation in the presence of [3H]choline released ACh having uniform specific activity. The data suggest the presence of more than one activity in the extracts.