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Title: Female reproductive state is associated with changes in distinct arginine vasotocin cell types in the preoptic area of Astatotilapia burtoni
Abstract

Nonapeptides play a crucial role in mediating reproduction, aggression, and parental care across taxa. In fishes,arginine vasotocin(AVT) expression is related to social and/or reproductive status in most male fishes studied to date, and is linked to territorial defense, paternal care, and courtship. Despite a plethora of studies examining AVT in male fishes, relatively little is known about how AVT expression varies with female reproductive state or its role in female social behaviors. We used multiple methods for examining the AVT system in female African cichlid fishAstatotilapia burtoni, including immunohistochemistry for AVT, in situ hybridization foravt‐mRNA, and quantitative PCR. Ovulated and mouthbrooding females had similar numbers of parvocellular, magnocellular, and gigantocellular AVT cells in the preoptic area. However, ovulated females had larger magnocellular and gigantocellular cells compared to mouthbrooding females, and gigantocellular AVT cell size correlated with the number of days brooding, such that late‐stage brooding females had larger AVT cells than mid‐stage brooding females. In addition, we found that ventral hypothalamic cells were more prominent in females compared to males, and were larger in mouthbrooding compared to ovulated females, suggesting a role in maternal care. Together, these data indicate that AVT neurons change across the reproductive cycle in female fishes, similar to that seen in males. These data on females complement studies in maleA.burtoni, providing a comprehensive picture of the regulation and potential function of different AVT cell types in reproduction and social behaviors in both sexes.

 
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NSF-PAR ID:
10454659
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Comparative Neurology
Volume:
529
Issue:
5
ISSN:
0021-9967
Page Range / eLocation ID:
p. 987-1003
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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