EFFECTS ON MISCELLANEOUS FUNCTIONS 243 



and above inhibits anaerobic glycolysis completely, and yet motility per- 

 sists. However, 0.5 mM iodoacetate reduces the motility aerobically during 

 the first 30 min and almost abolishes it during the next hour. Thus one 

 might be more inclined to conclude that motility is not immediately de- 

 pendent on glycolysis or oxidations, and that the stores of creatine-P and 

 ATP are sufficient to maintain activity for some time, and in this respect 

 the situation is not essentially different from muscle. Besides, 0.5 raM iodo- 

 acetate inhibits glucose utilization aerobically only 31% during the first 

 hour (Lardy and Phillips, 1943 a). The incorporation of C^^-labeled amino 

 acids into spermatozoa is not significantly reduced by 5 mM iodoacetate 

 aerobically, but anaerobically it is inhibited quite well, whereas motility 

 is abolished under both conditions (Bhargava et al., 1959). There seems to 

 be no correlation between motility and amino acid incorporation. Monroy 

 (1948) noted that the spermatozoa of Pomatoceros triqueter lose much of 

 their fertihzing ability in 1 milf iodoacetate but the motility is not impaired. 

 The spermatozoa cannot adhere to the vitelhne membrane, and it was sug- 

 gested that the lytic factor in the head may be an SH enzyme of cathepsin 

 type. 



Ciliary Motility 



The injection of 400 mg/kg bromoacetate into frogs leads to skeletal 

 muscle rigor, then cessation of the heart beat, but only later is there evi- 

 dence of depression of pharyngeal ciliary activity (Wertheimer, 1932). It 

 was stated that the cilia pass into a state of rigor, but this is admittedly 

 difficult to determine. Isolated pharyngeal cilia preparations show some de- 

 pression by 0.15-0.21 mil/ bromoacetate after 5 hr and a sporadic beating 

 within 2 hr in 0.31 mM bromoacetate. A concentration of 1.2 mM stops 

 the cilia in 1 hr. Pyruvate and lactate counteract these effects. Paramecium 

 motility is not affected by bromoacetate, even in combination with cyanide. 

 The cilia of the excised gills of the mussel Mytilus edulis show no alteration 

 of motility with 1 mM iodoacetate in sea water (pH of 8), although phos- 

 phate uptake is inhibited around 20%, and it was postulated that the lack 

 of action may be due to the failure to penetrate at this pH, any effects 

 observed being due to direct action on the proteins at the cell surfaces 

 (Ronkin, 1950). 



Vesicant Action of Iodoacetate 



The concept that vesication is related to the blocking of SH groups arose 

 during World War II in connection with the interest in war gases. Bacq 

 and Goffart (1940) pointed out that bromoacetic and iodoacetic acids are 

 quite potent vesicants when applied to the skin, the lesions being indistin- 

 guishable from those produced by the war gases and common vesicants such 

 as allyl isothiocyanate, chloroacetophenone, chloropicrin, and others. A lag 

 period of several hours was noted. Bacq (1941) claimed that vesicants in 



