Direkt zum Inhalt
Merck
  • Histamine H3 receptor activation stimulates calcium mobilization in a subpopulation of rat striatal neurons in primary culture, but not in synaptosomes.

Histamine H3 receptor activation stimulates calcium mobilization in a subpopulation of rat striatal neurons in primary culture, but not in synaptosomes.

Neurochemistry international (2016-11-05)
Nayeli Rivera-Ramírez, Wilber Montejo-López, María-Cristina López-Méndez, Agustín Guerrero-Hernández, Anayansi Molina-Hernández, Ubaldo García-Hernández, José-Antonio Arias-Montaño
ZUSAMMENFASSUNG

The histamine H3 receptor (H3R) is abundantly expressed in the Central Nervous System where it regulates several functions pre and postsynaptically. H3Rs couple to Gαi/o proteins and trigger or modulate several intracellular signaling pathways, including the cAMP/PKA pathway and the opening of N- and P/Q-type voltage-gated Ca2+ channels. In transfected cells, activation of the human H3R of 445 amino acids (hH3R445) results in phospholipase C (PLC) stimulation and release of Ca2+ from intracellular stores. In this work we have studied whether H3R activation induces Ca2+ mobilization from intracellular stores in native systems, either isolated nerve terminals (synaptosomes) or neurons in primary culture. In rat striatal synaptosomes H3R activation induced inositol 1,4,5-trisphosphate (IP3) formation but failed to increase the intracellular calcium concentration ([Ca2+]i). In striatal primary cultures H3R activation resulted in IP3 formation and increased the [Ca2+]i in 18 out of 70 cells that responded with an elevation in the [Ca2+]i to membrane depolarization with KCl (100 mM) as evaluated by microfluorometry. Confocal microscopy studies corroborated the increase in [Ca2+]i induced by H3R activation in a fraction of those cells that were responsive to membrane depolarization. These results indicate that H3R activation stimulates the PLC/IP3/Ca2+ pathway but only in a subpopulation of striatal neurons.

MATERIALIEN
Produktnummer
Marke
Produktbeschreibung

Sigma-Aldrich
U-73343
Sigma-Aldrich
Ciproxifan hydrochloride, ≥98% (HPLC), solid
Sigma-Aldrich
Imetit dihydrobromide, ≥98% (HPLC)
Sigma-Aldrich
Immepip dihydrobromide, ≥97% (HPLC), powder