Gold particles or cationic ferritin were initially used with electron microscopic analyses [44–46]. Segmental uptake of gold particles was seen at the cellular level for non-human primate inner-wall SC cells . Biological relevance was demonstrated through a conversion of segmental into a more homogenous pattern using a serine-threonine kinase inhibitor (H-7 (1-(5-isoquinoline sulfonyl)-2-methyl piperazine)) known to block actomyosin-driven contractility .