Avtor/Urednik     Čarman-Kržan, Marija; Lipnik-Štangelj, Metoda
Naslov     Molecular properties of central and peripheral histamine H1 and H2 receptors
Tip     članek
Vir     Pflugers Arch
Vol. in št.     Letnik 439, št. 3 Suppl
Leto izdaje     2000
Obseg     str. R131-2
Jezik     eng
Abstrakt     We identified and characterised histamine H1 and H2 receptor subtypes on rat cortical astrocytes in primary culture with radioligand binding studies and compared their molecular properties with peripheral (bovine vascular smooth muscle and endothelial cells) histamine H1 and H2 receptors. Our results showed the existence of a homogenous population of high affinity binding sites for 3H-mepyramine (Bmax= 281 fmol/mg protein, KD= 3.5 +/- 0.7 nM) and 3H-tiotidine (Bmax= 59 fmol/mg protein, KD 1.9 +/- 0.7 nM) on astrocytes, which was further confirmed by competition binding studies using various H1 and H2 specific agonists/antagonists. We showed differences in the density of receptors and differences in the affinities of competing drugs for the same histamine receptor subtype (H1 and H2) between the tissues used, which indicate different molecular properties of the central and peripheral histamine receptors.
Deskriptorji     RECEPTORS, HISTAMINE H1
RECEPTORS, HISTAMINE H2
ASTROCYTES
ENDOTHELIUM, VASCULAR
MUSCLE, SMOOTH, VASCULAR
RATS
CATTLE
RADIOLIGAND ASSAY