Activation of two different receptors mobilizes calcium from distinct stores in Xenopus oocytes

Journal Article · Fri Jun 01 04:00:00 EDT 1990 · Biophysical Journal; (USA)

DOI:https://doi.org/10.1016/S0006-3495(90)82646-1· OSTI ID:6511662

Shapira, H; Lupu-Meiri, M; Gershengorn, M C; Oron, Y ^[1]

---

1. Tel Aviv Univ., Ramat Aviv (Israel)

Acetylcholine (ACh) and thyrotropin-releasing hormone (TRH) utilize inositol 1,4,5-trisphosphate (IP3) as a second messenger and evoke independent depolarizing membrane electrical responses accompanied by characteristic {sup 45}Ca efflux profiles in Xenopus laevis oocytes injected with GH3 pituitary cell mRNA. To determine whether this could be accounted for by mobilization of calcium from functionally separate stores, we measured simultaneously {sup 45}Ca efflux and membrane electrical responses to ACh and TRH in single oocytes. We found that depletion of ACh-sensitive calcium store did not affect the membrane electrical response to TRH and the TRH-evoked {sup 45}Ca efflux. Our data suggest that ACh and TRH mobilize calcium from distinct cellular stores in the oocyte. This is the first demonstration in a single cell of strict subcellular compartmentalization of calcium stores coupled to two different populations of cell membrane receptors that utilize the same second messenger.

• OSTI ID: 6511662
• Journal Information: Biophysical Journal; (USA), Journal Name: Biophysical Journal; (USA) Vol. 57:6; ISSN 0006-3495; ISSN BIOJA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METALS
AMINES
AMMONIUM COMPOUNDS
AMPHIBIANS
ANIMALS
AQUATIC ORGANISMS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOELECTRICITY
BODY
CALCIUM
CALCIUM 45
CALCIUM ISOTOPES
CELL CONSTITUENTS
CELL MEMBRANES
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRICITY
ELEMENTS
ENDOCRINE GLANDS
ESTERS
EVEN-ODD NUCLEI
FROGS
GERM CELLS
GLANDS
HORMONES
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
MEMBRANE PROTEINS
MEMBRANE TRANSPORT
MEMBRANES
MESSENGER-RNA
METALS
NEUROREGULATORS
NUCLEI
NUCLEIC ACIDS
OOCYTES
ORGANIC COMPOUNDS
ORGANS
PARASYMPATHOMIMETICS
PEPTIDE HORMONES
PITUITARY GLAND
PITUITARY HORMONES
PROTEINS
QUATERNARY COMPOUNDS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
RNA
TRACER TECHNIQUES
TSH
VERTEBRATES