Marine Snail Conus Research Articles

Pharmacological investigation of the venoms of the marine snails Conus textile and Conus geographus

Phrenic nerve-diaphragm preparations and isolated skeletal muscles were exposed to two Conus venoms. Rats and mice were injected intraperitoneally. Anaesthetized rats and guinea-pigs were injected intravenously, the sciatic nerve being exposed and stimulated to give a foot twitch. Paralysis of diaphragm and other isolated muscles was observed only after administration of venom from the posterior half (approximately) of the venom duct of C. geographus. The anterior half of the duct of C. geographus and the whole of the duct of C. textile failed to yield venom capable of paralyzing isolated muscles or of causing symptoms in rats and mice on intraperitoneal injection. Venom active on isolated skeletal muscle caused respiratory failure in anaesthetized animals, the foot twitch response to sciatic nerve stimulation being simultaneously abolished. Recovery in both aspects usually occurred after artificial respiration. Active venom paralyzed skeletal muscle directly without prior neuromuscular blockade. However, there was enhancement of the effect of liminal doses of tubocurarine on the neuromuscular junction, and tubocurarine enhanced the muscle paralysis produced by small doses of venom. Eserine was without effect on the muscle paralysis.

A cholinergic mechanism of inhibitory synaptic transmission in a molluscan nervous system.

A cholinergic mechanism of inhibitory synaptic transmission in a molluscan nervous system.

Preliminary studies on the venom of the marine snail Conus.

Preliminary studies on the venom of the marine snail Conus.