Association of microperoxisomes with the endoplasmic reticulum in the granulosa lutein cells of the Rhesus monkey (Macaca mulatta).

Aldehyde fixed tissue from monkey (Macaca mulatta) corpus luteum was incubated in alkaline 3,3inch-diaminobenzidine (DAB), and prepared for electron microscopic histochemical observations. The association of microperoxisomes with the granular (GER) or agranular (AER) endoplasmic reticulum was reconstructed from serially sectioned tissues and by tilting of specimens in the microscope. Out of 107 microperoxisomes, 106 were directly associated with the AER. Two different forms of attachment were found between microperoxisomes and the AER and that of the microperoxisome are confluent. In the second, lingulate type of connection, a blunt-end structure either is inserted into an invagination of the AER, or penetrates into the lumen of the AER. The lumen of the lingula is confluent with the microperoxisome, but not with the AER. In addition to these connections, fine thread-like structures were observed extending between AER and adjacent microperoxisomes.