Monensin, a Na(+)-selective ionophore, enhances transmitter release when applied to crustacean and frog neuromuscular junctions. Monensin is believed to raise intracellular sodium ([Na+]i) which in turn elevates intracellular calcium ([Ca2+]i). Using the fluorescent indicator fura-2, we measured [Ca2+]i in crayfish Procambarus clarkii presynaptic terminals during monensin application in normal ...

A study was conducted to determine the toxicities (LC50S) of several pesticides on the commercially important red swamp crawfish, Procambarus clarkii, and 3 mosquito species common in Louisiana ricelands--Anopheles quadrimaculatus, Culex salinarius and Psorophora columbiae. Pesticides tested in laboratory bioassays included Bacillus sphaericus, B. thuringiensis var. israelensis, bendiocarb, gly...

The effect of methyl farnesoate (MF) on the ovaries of female red swamp crayfish, Procambarus clarkii, undergoing vitellogenesis was determined both in vivo and in vitro. The in vivo assay showed a positive effect of MF on oocyte growth when injected alone and in combination with 17 beta-estradiol, but not in combination with JHIII or 17 alpha-hydroxyprogesterone. A higher level of incorporatio...

The in vivo molt-inhibitory effects of the ecdysone biosynthesis inhibitors 3-hydroxy-L-kynurenine and xanthurenic acid were investigated. These ecdysone biosynthesis inhibitors, isolated from the eyestalks of blue crabs (Callinectes sapidus), were injected into eyestalk-ablated crayfish (Procambarus clarkii). The active factor was found to be species-nonspecific within crabs and crayfish. The ...

In this work the presence of different pharmaceuticals at Doñana National Park (Spain) and their main entry sources (input source or points) have been stated over 2011–2016 years period. Twenty-three selected (corresponding to eight therapeutic families) were evaluated in crayfish water samples from (six sampling points order cover possible pollution into surrounding Park). The multiresidue det...