The effects of a toxin isolated from Australian tiger snake (Notechis scutatus scutatus) venom on autonomic neuromuscular transmission. 1978

J B Harris, and M A Zar

1 The effects on mammalian autonomic neuromuscular transmission of a purified toxin from the crude venom of the Australian tiger snake, Notechis scutatus, have been investigated. 2 The toxin had no measurable effect on transmission in either the rat anococcygeus, the rat vas deferens, or the longitudinal muscle of the guinea-pig ileum. 3 The toxin induced a contraction of longitudinal smooth muscle of the ileum. The tissue relaxed in spite of the continued presence of the toxin, and remained insensitive to further doses. The contractile response was not mediated by either cholinergic or histaminergic mechanisms. 4 The toxin caused an inhibition of the response to field stimulation of the guinea-pig vas deferens and the guinea-pig seminal vesicle. The inhibition was spontaneously reversible, and the preparations remained insensitive to further doses fo the toxin. The effects of the toxin were not mediated by either prostaglandins or by noradrenaline. 5 The inhibitory effects of a variety of compounds known to act at presynaptic sites were also blocked by exposure to the toxin; inhibition caused by postsynaptic activity was unaffected by the toxin. 6 It is suggested that the toxin inhibits transmission in the guinea-pig vas deferens and seminal vesicle by a presynaptic mechanism. 7 The possibility that the mechanism involves phospholipase A2 activity is discussed.

UI MeSH Term Description Entries
D007082 Ileum The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.
D008297 Male Males
D009435 Synaptic Transmission The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES. Neural Transmission,Neurotransmission,Transmission, Neural,Transmission, Synaptic
D009469 Neuromuscular Junction The synapse between a neuron and a muscle. Myoneural Junction,Nerve-Muscle Preparation,Junction, Myoneural,Junction, Neuromuscular,Junctions, Myoneural,Junctions, Neuromuscular,Myoneural Junctions,Nerve Muscle Preparation,Nerve-Muscle Preparations,Neuromuscular Junctions,Preparation, Nerve-Muscle,Preparations, Nerve-Muscle
D012110 Reserpine An alkaloid found in the roots of Rauwolfia serpentina and R. vomitoria. Reserpine inhibits the uptake of norepinephrine into storage vesicles resulting in depletion of catecholamines and serotonin from central and peripheral axon terminals. It has been used as an antihypertensive and an antipsychotic as well as a research tool, but its adverse effects limit its clinical use. Raunervil,Raupasil,Rausedil,Rausedyl,Serpasil,Serpivite,V-Serp,V Serp
D001743 Urinary Bladder A musculomembranous sac along the URINARY TRACT. URINE flows from the KIDNEYS into the bladder via the ureters (URETER), and is held there until URINATION. Bladder,Bladder Detrusor Muscle,Detrusor Urinae,Bladder Detrusor Muscles,Bladder, Urinary,Detrusor Muscle, Bladder,Detrusor Muscles, Bladder
D004546 Elapid Venoms Venoms from snakes of the family Elapidae, including cobras, kraits, mambas, coral, tiger, and Australian snakes. The venoms contain polypeptide toxins of various kinds, cytolytic, hemolytic, and neurotoxic factors, but fewer enzymes than viper or crotalid venoms. Many of the toxins have been characterized. Cobra Venoms,Elapidae Venom,Elapidae Venoms,Naja Venoms,Cobra Venom,Elapid Venom,Hydrophid Venom,Hydrophid Venoms,King Cobra Venom,Naja Venom,Ophiophagus hannah Venom,Sea Snake Venom,Sea Snake Venoms,Venom, Cobra,Venom, Elapid,Venom, Elapidae,Venom, Hydrophid,Venom, King Cobra,Venom, Naja,Venom, Ophiophagus hannah,Venom, Sea Snake,Venoms, Cobra,Venoms, Elapid,Venoms, Elapidae,Venoms, Hydrophid,Venoms, Naja,Venoms, Sea Snake
D006168 Guinea Pigs A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research. Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D001341 Autonomic Nervous System The ENTERIC NERVOUS SYSTEM; PARASYMPATHETIC NERVOUS SYSTEM; and SYMPATHETIC NERVOUS SYSTEM taken together. Generally speaking, the autonomic nervous system regulates the internal environment during both peaceful activity and physical or emotional stress. Autonomic activity is controlled and integrated by the CENTRAL NERVOUS SYSTEM, especially the HYPOTHALAMUS and the SOLITARY NUCLEUS, which receive information relayed from VISCERAL AFFERENTS. Vegetative Nervous System,Visceral Nervous System,Autonomic Nervous Systems,Nervous System, Autonomic,Nervous System, Vegetative,Nervous System, Visceral,Nervous Systems, Autonomic,Nervous Systems, Vegetative,Nervous Systems, Visceral,System, Autonomic Nervous,System, Vegetative Nervous,System, Visceral Nervous,Systems, Autonomic Nervous,Systems, Vegetative Nervous,Systems, Visceral Nervous,Vegetative Nervous Systems,Visceral Nervous Systems

Related Publications

J B Harris, and M A Zar
January 1991, Toxicon : official journal of the International Society on Toxinology,
J B Harris, and M A Zar
June 1972, Toxicon : official journal of the International Society on Toxinology,
J B Harris, and M A Zar
January 1976, Toxicon : official journal of the International Society on Toxinology,
J B Harris, and M A Zar
July 1993, Toxicon : official journal of the International Society on Toxinology,
J B Harris, and M A Zar
January 1991, Toxicon : official journal of the International Society on Toxinology,
Copied contents to your clipboard!