Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.4.4 (adenosine deaminase)
 5,136 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A rat hippocampal preparation enriched in mossy fiber synaptosomes was employed in an attempt to expose any relationship between endogenous adenosine and the release of dynorphin B-like immunoreactivity (DynB-LI). Presumptive blockade of purinergic receptors increased the spontaneous release of DynB-LI, and reducing synaptic adenosine by exogenous adenosine deaminase increased the K(+)-evoked release. Evoked release of DynB-LI was reduced by inhibitors of adenosine uptake and 5'-nucleotidase. Taken together, these data suggest that adenosine endogenous to hippocampal mossy fiber synaptosomes serves to inhibit the release of one of the peptide neuromodulators of this preparation, and provide support for the concept of autoregulation of release.
 ...
PMID:Adenosine modulation of dynorphin B release by hippocampal synaptosomes. 135 16

In vitro lipid-mobilizing activities of morphine (MO) and dynorphin-(1-10) amide (DYA) were compared using adipocytes of young adult rats (body weight 170-200 g, age 50-60 days, diameter of adipocytes 54 +/- 1.12 microns) and of 20-month-old rats (body weight 500-690 g, diameter of adipocytes 99.5 +/- 3.0 microns). The adipokinetic activities of adenosine deaminase (ADA) and dynorphin-(1-13) (DY) were also tested. In the experiments 0.16 units of ADA did not influence basal or stimulated lipolysis, whereas DY exerted a slight but statistically significant adipokinetic effect. In three experimental series the EC50 of MO ranged between 0.89 and 14.60 mumol l-1, the EC50 of DYA in young rats was estimated as 0.8 mumol l-1 and in old animals, 1.3 mumol l-1. Statistically significant differences in the lipid-mobilizing potency between DYA and MO could be observed only in one experimental series in young rats. Expressed in percent of maximum lipolysis induced by isoprenaline, the maximum lipolytic response to DYA in young animals was significantly lower (Emax 26.1 +/- 1.9) when compared to the maximum effect of MO (Emax 76.3 +/- 8.5 and 68.9 +/- 3.5, respectively). Adipocytes of old rats seemed to be more sensitive not only against MO but also against DYA. When studying lipolysis no signs of competitive dualism could be observed in the interaction between MO and DYA. The possibility of two or more independent lipid-mobilizing mechanisms in the effect of the two opioids compared cannot be excluded.
 ...
PMID:Morphine and dynorphins in lipid mobilization in rats in vitro. 288 30