STUDY OF THE FRACTION XVII-B_2 FROM THE VENOM OF NAJA NAJA ATRA
- VernacularTitle:中华眼镜蛇毒组份ⅩⅤⅡ—B_2的研究
- Author:
Ze ZHANG
;
Benyong HU
- Publication Type:Journal Article
- Keywords:
Neurotoxin;
Receptor;
Acetylcholine
- From:
Chinese Pharmacological Bulletin
1986;0(05):-
- CountryChina
- Language:Chinese
-
Abstract:
The venom of Naja naja atra from Guangdong province has been separated into 27 fractions by CM-Sephadex C-25 column chromatog-raphy. One lethal toxin fraction was further purified by ion-exchange rechromatography on CM-Sephadex C-50 and by gel filtration on Sep-hadex G-50 and was named fraction XVII-B2. It can abolish the responses of chikea biventer cervisis muscle to indirect stimulation or to Ach. but not affects the responses to direct stimulation Or K+. On the other hand, it has no effects on Straub's frog hearts in vitro,but its LD50 for mice is about 75ug/kg.Slab-PAGE, SDS-PAGE and isoelectrofocusing were performed to test the homogeneity of the fraction. Some immunological methods were also used. The molecular weight and pl for this fraction are about 7200 daltons by SDS-PAGE and pH 8.5 by isoelectrofocusing. The resemblance between the fraction and cobratoxin has been analysed by comparing the amino acid composition. We have used it successfully in radio ligand assay of nicotinic receptor preparations from Narcine maculata electric organ.The experiment data show that the fraction may be a short post-synaptic neurotoxin and may be an effective tool In studies of acetyl-choline receptor.
