STIMULATION OF BOVINE SPERM MOTILITY AND RESPIRATION BY THE TRIAZINE DYE CIBACRON BLUE F3GA

Bovine sperm motility and respiration were stimulated by the triazine dye Cibacron Blue F3GA (CB), which may operate as a nucleotide mimic. CB stimulation of respiration was half-maximal at about 35 mu M and re spiration reached maximal levels about 1.5 minutes after CB addition. Respiratory stimulation was preceded by a transient increase in cytoso lic cAMP. Sperm cAMP titers were elevated from 5 to 10 pmoles/10(8) ce lls within 30 seconds of CB addition, but rapidly dropped to a stable level of about 7.5 pmoles/10(8) cells. CB was a potent inhibitor of sp erm membrane adenylyl cyclase and inhibited respiration in permeabiliz ed cells. Taken together, the data indicated that CB stimulation was n ot manifested via the cytosol. In addition, a nonpermeant blue dextran preparation synthesized with CB also stimulated sperm respiration and motility. CB inhibited sperm membrane phosphodiesterase activity, sug gesting that the transient pulse of cAMP resulted from CB interaction with this enzyme in the sperm membrane. (C) 1995 Wiley-Liss, Inc.