The full stereochemistry of the grayanotoxins and a novel rearrangement

Kozima, T.; Nakanishi, Koji; Yanai, Makoto; Kakisawa, Hiroshi

doi:10.1016/s0040-4039(00)90476-3

Cited by 8 publications

(4 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The toxins contain several analogues, and their chemical structures have been completely identified (Kakisawa, Kurono, Nakanishi & Hirata, 1961; Kakisawa, Kozima, Yanai & Nakanishi, 1965 Kozima, Nakanishi, Yanai & Kakisawa, 1964;Kumazawa & Iriye, 1970;Matsumoto & Watanabe, 1968). Grayanotoxin I (Fig.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mechanism of nerve membrane depolarization caused by grayanotoxin I

Narahashi¹,

Seyama²

1974

The Journal of Physiology

101

View full text Add to dashboard Cite

SUMMARY1. The mechanism of depolarization of squid axon membranes caused by grayanotoxin I has been studied by means of internal perfusion and voltage clamp techniques.2. The depolarization induced by either internal or external application of grayanotoxin I was reversed by decreasing the external sodium concentration from 449 to 1 mmw.3. No depolarization was observed when both external and internal media were devoid of sodium ions, indicating that the depolarization by grayanotoxin I in normal media is due to a specific increase in resting sodium permeability.4. The resting sodium permeability as measured by voltage clamp was increased to 1'31 x 106 cm/sec by internal application of 1 x 10-5 M arayanotoxin I, an increase by a factor of about 90.5. The apparent dissociation constant of internally applied grayanotoxin I in increasing the resting sodium permeability was estimated to be 412 x 10-5 M, and the toxin interacts with the membrane receptor on a one-to-one stoichiometric basis.6. Tetrodotoxin antagonized the action of grayanotoxin I in increasing the resting sodium permeability in a non-competitive manner.

show abstract

Section: Introductionmentioning

confidence: 99%

“…Chemical structure of grayanotoxin I. Kozima, Nakanishi, Yanai & Kakisawa, 1964;Kumazawa & Iriye, 1970;Matsumoto & Watanabe, 1968). Grayanotoxin I (Fig.…”

Section: Introductionmentioning

confidence: 99%

Mechanism of nerve membrane depolarization caused by grayanotoxin I

Narahashi¹,

Seyama²

1974

The Journal of Physiology

101

View full text Add to dashboard Cite

show abstract

“…and batrachotoxin, a frog toxin, are both steroids containing an unusual hemiketal bridge (3a, 9a and 4ac, 9a, respectively) and a tertiary nitrogen in a ring attached to the steroid D ring (18,19). Aconitine and the non-nitrogenous diterpenoid grayanotoxin share a fused 5-, 7-, and 6-membered ring system (20,21) and bear little structural similarity to veratridine and batrachotoxin. The toxins of scorpion venom are basic polypeptides with molecular weights of approximately 7000 (22).…”

mentioning

confidence: 99%

Cooperative activation of action potential Na+ ionophore by neurotoxins.

Catterall¹

1975

Proc. Natl. Acad. Sci. U.S.A.

167

122

View full text Add to dashboard Cite

Four neurotoxins that activate the action potential Na+ ionophore of electrically excitable neuroblastoma cells interact with two distinct classes of sites, one specific for the alkaloids veratridine, batrachotoxin, and aconitine, and the second specific for scorpion toxin. Positive heterotropic cooperativity is observed between toxins bound at these two classes of sites. Tetrodotoxin is a noncompetitive inhibitor of activation by each of these toxins (K1 = 4-8 nM). These results suggest the existence of three functionally separable components of the action potential Na+ ionophore: two regulatory components, which bind activating neurotoxins and interact allosterically in controlling the activity of a third ion-transport component, which binds tetrodotoxin.

show abstract

“…Veratridine, a plant alkaloid, and batrachotoxin, a frog toxin, are both steroids containing an unusual hemiketal bridge (3a, 9a and 4ac, 9a, respectively) and a tertiary nitrogen in a ring attached to the steroid D ring (18,19). Aconitine and the non-nitrogenous diterpenoid grayanotoxin share a fused 5-, 7-, and 6-membered ring system (20,21) and bear little structural similarity to veratridine and batrachotoxin. The toxins of scorpion venom are basic polypeptides with molecular weights of approximately 7000 (22).…”

Section: Methodsmentioning

confidence: 99%

Cooperative activation of action potential Na ⁺ ionophore by neurotoxins

1975

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

The full stereochemistry of the grayanotoxins and a novel rearrangement

Cited by 8 publications

References 9 publications

Mechanism of nerve membrane depolarization caused by grayanotoxin I

Mechanism of nerve membrane depolarization caused by grayanotoxin I

Cooperative activation of action potential Na+ ionophore by neurotoxins.

Cooperative activation of action potential Na ⁺ ionophore by neurotoxins

Contact Info

Product

Resources

About

The full stereochemistry of the grayanotoxins and a novel rearrangement

Cited by 8 publications

References 9 publications

Mechanism of nerve membrane depolarization caused by grayanotoxin I

Mechanism of nerve membrane depolarization caused by grayanotoxin I

Cooperative activation of action potential Na+ ionophore by neurotoxins.

Cooperative activation of action potential Na + ionophore by neurotoxins

Contact Info

Product

Resources

About

Cooperative activation of action potential Na ⁺ ionophore by neurotoxins