It is well established that cytosolic calcium (Ca²⁺) acts as a key second messenger in many intracellular pathways including synaptic transmission, muscle contraction, hormonal secretion, cell growth and proliferation.^1,2  The primary intracellular Ca²⁺ storage/release organelles in most cells is the endoplasmic reticulum (ER) or the sarcoplasmic reticulum (SR) in striated muscle cells.

The ER and SR contain two Ca²⁺ release channel families, the Inositol trisphosphate receptors (IP3Rs) and the Ryanodine receptors (RyRs).³

The Ryanodine receptor family consists of three different isoforms: The skeletal muscle isoform, Ryanodine Receptor type 1 (RyR1); the cardiac muscle isoform, Ryanodine Receptor type 2 (RyR2) and the brain isoform, Ryanodine Receptor type 3 (RyR3).³ The Ryanodine receptors are homotetrameric proteins generating a Ca²⁺ conducting channel. They play a key role in the mechanism of excitation-contraction coupling in striated muscle. Binding of Ryanodine (poisonous alkaloid found in the South American plant Ryania speciosa) to the Ryanodine receptor causes two major changes in the channel: a reduction in single-channel conductance and a marked increase in the open state probability, leading to an overall increase/decrease in the Ca²⁺ release capability of the channel.

RyR3 is the most widely expressed RyR channel which is predominantly expressed in smooth muscle tissues and certain regions of the brain.

Alomone Labs is pleased to offer a highly specific antibody directed against an epitope putatively located at the cytoplasmic region of the human Ryanodine receptor 3 (RyR3). The Anti-Ryanodine Receptor 3 antibody (#ARR-003) can be used for western blot analysis and Immunohistochemical applications. It has been designed to recognize RyR3 from human, rat and mouse samples.