The subcellular distribution and partial characterization of cholinesterase activities of canine platelets

Isolation of Platelet Membranes. A Review

“…Contradictory results were reported with the nitrogen decompression technique with the Parr bomb , Broekman 1974, Lovette 1976 as well as with Aminco-French press (French 1974, Salganicoff 1975. Relatively little organelle disruption (8% B-N-acetyl glucosaminidase solubilized) was found with nitrogen decompression (Lovette 1976) but the cell disruption varied from 75% in humans (Barber 1971 b) to 90% in dogs (Lovette 1976). 90% lysis of cell but also 40% solubilization of B-N-acetyl glucosaminidase and 60% of serotonin was reported with the French press at a pressure of 1361 atm with human platelets (French 1974).…”

“…Combinations of gentle pestle homogenization with osmotic lysis of glycerol loaded cells may disrupt thrombin-treated platelets that are otherwise resistent to lysis (Rittenhouse 1976). Lovette (1976) found 56% of canine platelets to be disrupted. About 40% of ~-N-acetyl glucosaminidase had been solubilized.…”

“…Mitochondria: The marker generally used for mitochondria is succinic dehydrogenase (Salganicoff 1975, Lovette 1976, Harris 1973, Taylor 1974, Barber 1970, but cytochrome oxydase has also been employed (Broekman 1972, Day 1969, Marcus 1966, Taylor 1976. These enzymes are located in the matrix of the mitochondria (de Duve 1971 ).…”

“…Added extracellular markers such as radiolabeled lentil lectin (Rittenhouse 1976), which has a specificity for glucose and mannose, labeled platelet antibodies (Taylor 1974) and labeled thrombin (Lovette 1976) have been utilized to advantage. Similarly, labeling of membrane proteins has been carried out with the lactoperoxydase technique (Taylor 1976).…”

“…Both processes are membrane mediated phenomena and much interest has been raised in the composition and function of the platelet plasma membrane. Specific membrane glycoproteins have been identified, (Jenkins 1976a, Okumura 1976a, b, Solum 1977) a number of specific transport processes have been described (Sixma 1973(Sixma , 1976 and several substances have been used as membrane probes under various conditions (Phillips 1972, Gates 1975, Rittenhouse 1976, Lovette 1976. Several investigators have tried to isolate plasma membranes without contamination with cell organelles but this appeared to be difficult.…”