Ca2+ puff

Ca2+ puffs in response to application of agonists to the cells, and Ca2+ waves. Boittin et al (2000) were also able to show these events following the photorelease of L1SP3 from caged precursors. They proposed that Ca2+ release is initiated at one site and then spreads as a wave, by a spatial recruitment of neighbouring Ca2+ release sites . 

STOCs arise from the concerted activation of up to 100 Ca2+-activated K+ channels (KCa) in the sarcolemma as a consequence of Ca2+ release from the SR. This release may take the form either of non-propagating focal events such as sparks or puffs , or of more regenerative Ca2+ waves. Since a temporal correlation between them exists, STOCs have been attributed to focal nonpropagating Ca2+ release events. However, this view requires that each STOC is a spatially restricted membrane current that occurs at selected areas of membrane closely apposed to the SR. While essential to the prevalent hypothesis for STOCs,... 

Parker, I., Choi, J., and Yao, Y. (1996) Elementary events of InsP3-induced Ca2+ liberation in Xenopus oocytes hot spots, puffs and blips. Cell Calcium, 20 105-121. 

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