What is the microtrabecula?
D000311:Adrenal Glands / Q000648:ultrastructure; D000818:Animals; D003593:Cytoplasm / Q000648:ultrastructure; D003599:Cytoskeleton / Q000648:ultrastructure*; D008854:Microscopy, Electron / Q000379:methods; D009940:Organoids / Q000648:ultrastructure; D051381:Rats