Basic biochemistry would suggest this to be paradoxical. CN- should stop the sperm in their tracks! I have no answer to offer, but what is the effect on other (birds, fish, mammals) sperm cells?

Insect sperm are a little different, they do not have mitochondria. Some do require oxygen but many species rely on glycolosis for ATP production

Very interesting indeed.....I have no explanation.

Thanks Brandon for the explanation. I assumed that all sperm are packed with mitochondria and so would need Fe/Cu. in this case then CN- should have not kill insect sperm but why does it then appear to accelerate them? ( doe it is anyway supply a means of getting rid of glycolytic excesses or provide some respiratory advantages?

All I can think of is that KCN is used to mimic hypoxia in brain slice preparations. Some cells increase their firing rate in the presence of hypoxia perhaps as a protective response I guess. Maybe that is what is happening with the sperm cells.

Anita, thank you, I had not heard of that. Do know of a reference to the increased firing rate in hypoxic condition

Hi Brandon,

The following might be a start:

Oxygen-sensing neurons in the central nervous system

Judith A. Neubauer and Jagadeeshan Sunderram

J Appl Physiol 96: 367-374, 2004;

Hypoxia-activated Ca2+ currents in pacemaker neurones of rat rostral ventrolateral medulla in vitro.

M K Sun and D J Reis

J Physiol. Apr 1, 1994; 476(1): 101–116.

Cyanide excites medullary sympathoexcitatory neurons in rats.

M K Sun; I T Jeske; Donald J Reis

The American journal of physiology 1992;262(2 Pt 2):R182-9.

Also Patrice G. Guyenet, and Ruth Stornetta, University of Virginia have done a lot with central respiratory chemoreception.

Good luck

Anita