Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
1981-4-24
pubmed:abstractText
Apamin (10(-7) M), a substance extracted from bee venom (apis mellifica) causes stimulation of the taenia caeci as seen from an increase in spike activity. The inhibitory effect of ATP or adrenaline (Adr) was reflected by hyperpolarization of the muscle cell, cessation of spike activity and relaxation of the muscle. The 42K efflux and the membrane conductance were enhanced in the presence of these substances. Apamin converted the hyperpolarization caused by ATP or Adr into a transient depolarization which produced contraction of the muscle cells. The changes in membrane conductance and 42K efflux were diminished by the bee toxin. Furthermore, the potassium-dependent phase of the action potential was lengthened by apamin. Reduction of the extracellular chloride or sodium concentration, blockade of the nervous system by TTX (3 x 10(-7) M) or inhibition of spike activity by D600 (3 x 19(-6) M) did not affect the excitatory and blocking action of apamin. A high concentration of the calcium antagonist D600 (10(-4) M) or omission of extracellular calcium was needed to reduce the transient depolarization evoked by ATP or Adr in the presence of apamin. It is concluded that apamin prevents the opening of the ATP- and Adr-sensitive and voltage-dependent potassium channels in guinea-pig taenia caeci.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0014-2999
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
265-74
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
The action of apamin on guinea-pig taenia caeci.
pubmed:publicationType
Journal Article, In Vitro