108 FACTORS AFFECTING CILIARY ACTIVITY 



destroys the effect on ciliary activity. These results have been 

 confirmed by Usuki (1959), who, using similar material from the 

 frog as w^ell as ciliated epithelia from the gills and palps of the 

 oyster, obtained an acceleration of ciliary activity at ATP con- 

 centrations between S-SxlO""^ and 3-3xlO~^mol; there W2ls 

 also an increase in the secretion of mucus. Usuki also used a 

 histochemical method which enabled him to demonstrate the 

 presence of ATP-ase in the cilia and epithelial cells of the oyster 

 and the frog, and the mucus-secreting cells of the oyster. The 

 ATP-ase may be located in the actual ciliary shafts, for isolated 

 cilia of the protozoon Tetrahytnena possess enzymatic activity 

 capable of splitting ATP, ADP and A-5-MP (Child, 1958). An 

 extract of flagella of Polytonia was found by Tibbs (1957) to split 

 ATP, ADP, AMP and beta-glycerophosphate (see also p. 29). 

 Lansing and Lamy (1961b) have used a technique that shows 

 localization of ATP-ase activity as a deposit of lead; in electron 

 micrographs of the cilia of the rotifer Philodina the metallic deposit 

 appeared in well-defined regions outside peripheral fibrils 1 and 

 5 of the ciliary shafts. 



ATP also acts as the energy carrier for the movement of sperma- 

 tozoa. It has been found in both ram sperm (Mann, 1945) and 

 sea urchin sperm (Rothschild and Mann, 1950), and perch sperm 

 contain an ATP-ase (Tibbs, 1959). Mytilus sperm tails have been 

 shown to contain an ATP-ase whose activity could be increased 

 by addition of magnesium chloride, and to a lesser extent by 

 addition of calcium chloride (Nelson, 1955). The ATP-ase 

 activity of the sea urchin sperm was found by Mohri (1958) to 

 be mainly located in the tail, with a small proportion in the 

 mid-piece. Using biochemical data obtained from bull sperm 

 Nelson, (1958) has calculated that more energy than that required 

 for movement could be liberated by succinic dehydrogenase 

 activity (i.e. through the respiratory activities outlined above) and 

 carried by the ATP present; the necessary enzymes seem to be 

 present in the tail, and Nelson believes them to be located in the 

 outer nine fibrils. ATP-ase activity in bull sperm seems to be 

 associated with a myosin-like component that Bishop (1958d) has 

 found in the sperm tails; this confirms the similarity of the 

 relationship between ATP and cilia to that between ATP and 

 muscle. These two relationships are also similar in that the action 



