Distribution of  Gamma-aminobutyric acid (GABA) in the central nervous system of the male mud crab, Scylla olivacea

Session

LSA.1 - Label-free life science imaging

Authors

Miss Kanjana Khornchatri (3), Mr. Jirawat Saetan (2), Miss Sirirak Mukem (4), Mr. Prasert Sobhon (1), Miss Tipsuda Thongbuakaew (4)

Affiliations

1. Mahidol University
2. Prince of Songkla University
3. Thammasat University
4. Walailak University

Keywords

GABA, immunocytochemistry, central nervous system, neuronal clusters, mud crab, Scylla olivacea

Abstract text

Mud crab, Scylla olivacea is one of the most important economic value marine species in the world (1). Recently, its population is rapidly decreasing, thus the understanding of neurotransmitters/ neurohormones/ neuromodulators controlling of reproduction may help to improve the productivity in aquaculture. Many studies have reported the mechanisms of several neurotransmitters or neurohormones that involved in the reproduction of decapod crustaceans, especially serotonin, octopamine, and dopamine (2, 3). They were detected throughout the central nervous system (CNS) of decapod crustaceans, which control the reproduction via regulating various neuropeptides. Gamma-aminobutyric acid (GABA) has implicated in the modulation of numerous physiological functions, including reproduction in many invertebrate species (4, 5). However, the existence of GABA in the mud crab, Scylla olivacea remains unclear. We aim to investigate the distribution of GABA throughout the CNS by a combination of immunohistochemistry and confocal laser scanning microscopy on whole‐mount immunofluorescence technique. The result revealed a ubiquitous distribution of GABA immunoreactivity (-ir) throughout the CNS. In the brain, GABA-ir was detected in the neuronal clusters 6, 7, 9, 10, 11, 12, 13, 14, 15, 16, 17, and fibers, including olfactory neuropil (ON), circumesophageal connective (CEC), and antenna II neuropil (AnN).  In the ventral nerve cord, GABA-ir was broadly found in subesophageal ganglion (SEG), thoracic ganglion (TG), and abdominal ganglion (AG). GABA-ir was detected in the small- and medium-sized neurons in the SEG.  In the TG, GABA-ir was also presented in the large-sized neurons between thoracic neuropils (TN) and fiber around the thoracic artery (TA). Moreover, GABA-ir was found in the medium- and large-sized neurons in the AG. Therefore, the existence and distribution of GABA in the male mud crab, Scylla olivacea may suggest that GABA may play a role in the controlling of reproduction via stimulating neuropeptides release in the CNS.

References

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