Send to

Choose Destination
See comment in PubMed Commons below
Biochem J. 1993 Apr 1;291 ( Pt 1):163-8.

Different modulatory effects of elevated cyclic AMP on cytosolic Ca2+ spikes induced by phenylephrine or vasopressin in single rat hepatocytes.

Author information

Department of Human Anatomy and Cell Biology, University of Liverpool, U.K.


We show here, by aequorin measurements in single isolated rat hepatocytes, that elevation of cyclic AMP, by dibutyryl cyclic AMP, forskolin or glucagon, has different effects on oscillations in cytosolic concentration of free Ca2+ ('free Ca') induced by phenylephrine or vasopressin. Elevated cyclic AMP does not itself induce free Ca oscillations, but enhances both the peak free Ca and the frequency of spikes induced by phenylephrine. In contrast, elevated cyclic AMP has no effect on peak free Ca of vasopressin-induced spikes, but markedly prolongs the falling phase, with the result that spiking frequency (peak to peak) falls, although the period between spikes of resting free Ca is usually decreased. The data provide another example of receptor-specific information being retained in the oscillator mechanism, with implications for models of the hepatocyte calcium oscillator.

[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center