Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    The journal of membrane biology 141 (1994), S. 101-112 
    ISSN: 1432-1424
    Keywords: Rat insulinoma cell line ; CRI-G1 ; Nucleotide regulation ; Calcium-activated nonselective cation channel ; Patch clamp
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The nucleotide regulation of a calcium-activated nonselective cation (Ca-NS+) channel has been investigated in the rat insulinoma cell line CRI-G1. The activity of the channel is reduced by both AMP and ADP (1–100 μm) in a concentration-dependent manner, with AMP being more potent than ADP. At lower concentrations (0.1–5 μm), both ADP and AMP activate the channel in some patches. Examination of the nucleotide specificity of channel inhibition indicates a high selectivity for AMP over the other nucleotides tested with a rank order of potency of AMP 〉 UMP 〉 CMP ≥GMP. Cyclic nucleotides also modulate channel activity in a complex, concentration-dependent way. Cyclic AMP exhibits a dual effect, predominantly increasing channel activity at low concentrations (0.1–10 μm) and reducing it at higher concentrations (100 μm and 1 mm). Specificity studies indicate that the cyclic nucleotide site mediating inhibition of channel activity exhibits a strong preference for cyclic AMP over cyclic GMP, with cyclic UMP being almost equipotent with cyclic AMP. Cyclic IMP and cyclic CMP are not active at this site. The cyclic nucleotide site mediating activation of the channel shows much less nucleotide specificity than the inhibitory site, with cyclic AMP, cyclic GMP and cyclic IMP being almost equally active.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-1424
    Keywords: Calcium-activated nonselective channel ; Rat insulinoma cell line ; CRI-G1 ; Pyridine nucleotides β-NAD+-NS+ channel ; Nucleotide regulation ; AMP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The activity of a calcium-activated nonselective (Ca-NS+) channel in a rat insulinoma cell line (CRI-G1) is inhibited by pyridine nucleotides in excised patches. The effects of all four pyridine nucleotides tested, β-NAD+, β-NADH, β-NADP+ and β-NADPH were very similar when tested at 0.1 mm, and at 1 mm the phosphorylated forms, β-NADP+ and β-NADPH, appeared to be slightly more potent than β-NAD+ and β-NADH. All the pyridine nucleotides tested reduced both the open state probability of the channel and the number of functional channels observed in a single patch. The application of β-NAD+, but not of the other nucleotides tested, to the cytoplasmic surface of isolated inside-out patches from CRI-G1 cells opened a novel nonselective cation channel (the β-NAD+-NS+ channel). The activity of this new channel is calcium sensitive and may also be inhibited by AMP.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...