Dopamine inhibition of tryptophan hydroxylase in molluscan nervous tissue homogenates: evidence for intracellular site of action

The discovery of combined toxicity effects and mechanisms of hexaconazole and arsenic to mice based on untargeted metabolomics

The high detected frequencies of hexaconazole (Hex) and arsenic (As) increased the probabilities of their co-existence in agricultural products. However, the combined toxicity effect and mechanism of action for these two pollutants were still unclear. In this study, an untargeted metabolomics method with ultra high performance liquid chromatography and tandem mass spectrometry (UPLC-MS/MS) was developed to monitor the changes of endogenous metabolites and metabolism pathways in mice liver. Our study revealed that significant differences in metabolomics profiles were observed after Hex, As, and Hex+As exposure for 90 d. Hex exposure altered 54 metabolites and 11 pathways significantly which were mainly lipid-related. For As exposure, 63 metabolites and 9 pathways were affected most of which were amino acid-related. Hex+As induced 93 metabolites changes with 34% was lipids and lipid-like molecules and 22% was organic acids and derivatives. Hex+As exposure shared the pathways that altered by Hex and As indicated that the interaction of Hex and As might be independent action. The results of this study could provide an important insight for understanding the mechanism of combined toxicity for Hex and As and be helpful for evaluating their health risk to human.

Monoaminergic and cholinergic mechanisms of reproduction control in marine bivalve molluscs and echinoderms: a review

The autoreproduction ability is one of the most important properties of living systems. Evolution of metazoans ensured their reproduction by means of such determinants as sexual cells developing in specialized organs, in gonads. In most marine invertebrates, the gonad produces tens of millions of gametes per reproductive cycle. This reproduction level guarantees the species resistance in the external environment and is provided by the whole organism, though in unfavourable ecological conditions the gonad may become a source of trophic and energy material and it can maintain the viability of organism by means or the mass, often total, lysis of sexual cells. This metabolic interaction of a part (gonad) and the whole (organism) presumes the existence of the strictly determined relations between them, on the one hand, and more or less pronounced autonomy, on the other hand. The isolated organs, including gonads, are capable of fulfilling specific functions for a short period of time by means of local regulation. However, there is no full autonomy between the gonad and the organism: the hierarchical relations set in between them.