H/sub 1/-histamine receptors regulate phosphoinositide hydrolysis in human astrocytoma cells

Conference · Wed Mar 05 00:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6991847

Nakahata, N; Harden, T K

Activation of H/sub 1/-histamine receptors on 1321N1 human astrocytoma cells resulted in a rapid formation of the inositol phosphates (InsP), IP/sub 3/, IP/sub 2/, and IP/sub 1/. Histamine-induced mobilization of Ca/sup + +/ and stimulated of a Ca/sup + +/ calmodulin-regulated phosphodiesterase occurred concurrently with histamine-stimulated InsP formation. The K/sub 0.5/ values for histamine for activation of phosphodiesterase, mobilization of Ca/sup + +/, and stimulation of InsP formation were 3,4, and 10 ..mu..M, respectively. The K/sub i/ for histamine determined in competition binding experiments with the H/sub 1/-receptor antagonist, /sup 3/H-mepyramine, was 11 ..mu..M. As with muscarinic receptor-mediated effects in these cells, inactivation of G/sub i/ with pertussis toxin had no effect on H/sub 1/-receptor mediated responses. Both histamine and muscarinic receptor stimulation resulted in the formation of Ins 1,4,5P/sub 3/ and Ins 1,3,4P/sub 3/. In contrast to muscarinic receptor stimulation, which results in a linear accumulation of InsP for greater than 30 min, histamine-stimulated formation of InsP rapidly desensitized.

• Research Organization: Univ. of North Carolina School of Medicine, Chapel Hill
• OSTI ID: 6991847
• Report Number(s): CONF-8604222-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:4; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
HISTAMINE
RECEPTORS
PHOSPHODIESTERASES
ENZYME ACTIVITY
PHOSPHOLIPIDS
HYDROLYSIS
CALCIUM COMPOUNDS
CATIONS
MAN
TRACER TECHNIQUES
TRITIUM COMPOUNDS
TUMOR CELLS
ALKALINE EARTH METAL COMPOUNDS
AMINES
ANIMAL CELLS
ANIMALS
AZOLES
CHARGED PARTICLES
CHEMICAL REACTIONS
DECOMPOSITION
ENZYMES
ESTERASES
ESTERS
HETEROCYCLIC COMPOUNDS
HYDROLASES
IMIDAZOLES
IONS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LIPIDS
LYSIS
MAMMALS
MEMBRANE PROTEINS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PRIMATES
PROTEINS
SOLVOLYSIS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques