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Title: Distribution and female reproductive state differences in orexigenic and anorexigenic neurons in the brain of the mouth brooding African cichlid fish, Astatotilapia burtoni
Abstract

Integration of reproduction and metabolism is necessary for species survival. While the neural circuits controlling energy homeostasis are well‐characterized, the signals controlling the relay of nutritional information to the reproductive axis are less understood. The cichlid fishAstatotilapia burtoniis ideal for studying the neural regulation of feeding and reproduction because females cycle between a feeding gravid state and a period of forced starvation while they brood developing young inside their mouths. To test the hypothesis that candidate neuropeptide‐containing neurons known to be involved in feeding and energy homeostasis in mammals show conserved distribution patterns, we performed immunohistochemistry and in situ hybridization to localize appetite‐stimulating (neuropeptide Y, NPY; agouti‐related protein, AGRP) and appetite‐inhibiting (cocaine and amphetamine‐regulated transcript, CART; pro‐opiomelanocortin,pomc1a) neurons in the brain. NPY, AGRP, CART, andpomc1asomata showed distribution patterns similar to other teleosts, which included localization to the lateral tuberal nucleus (NLT), the putative homolog of the mammalian arcuate nucleus. Gravid females also had larger NPY and AGRP neurons in the NLT compared to brooding females, but brooding females had largerpomc1aneurons compared to gravid females. HypothalamicagrpmRNA levels were also higher in gravid compared to brooding females. Thus, larger appetite‐stimulating neurons (NPY, AGRP) likely promote feeding while females are gravid, while largerpomc1aneurons may act as a signal to inhibit food intake during mouth brooding. Collectively, our data suggest a potential role for NPY, AGRP, POMC, and CART in regulating energetic status inA. burtonifemales during varying metabolic and reproductive demands.

 
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NSF-PAR ID:
10027957
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Comparative Neurology
Volume:
525
Issue:
14
ISSN:
0021-9967
Format(s):
Medium: X Size: p. 3126-3157
Size(s):
p. 3126-3157
Sponsoring Org:
National Science Foundation
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