Distribution of brain oxytocin and vasopressin V1a receptors in chimpanzees (Pan troglodytes): comparison with humans and other primate species.

Bibliographic Collection: 
Publication Type: Journal Article
Authors: Rogers Flattery, Christina N; Coppeto, Daniel J; Inoue, Kiyoshi; Rilling, James K; Preuss, Todd M; Young, Larry J
Year of Publication: 2022
Journal: Brain Struct Funct
Volume: 227
Issue: 5
Pagination: 1907-1919
Date Published: 2022 Jun
Publication Language: eng
ISSN: 1863-2661
Keywords: Animals, Brain, Humans, Oxytocin, Pan troglodytes, Receptors, Oxytocin, Receptors, Vasopressin, Social Behavior

Despite our close genetic relationship with chimpanzees, there are notable differences between chimpanzee and human social behavior. Oxytocin and vasopressin are neuropeptides involved in regulating social behavior across vertebrate taxa, including pair bonding, social communication, and aggression, yet little is known about the neuroanatomy of these systems in primates, particularly in great apes. Here, we used receptor autoradiography to localize oxytocin and vasopressin V1a receptors, OXTR and AVPR1a respectively, in seven chimpanzee brains. OXTR binding was detected in the lateral septum, hypothalamus, medial amygdala, and substantia nigra. AVPR1a binding was observed in the cortex, lateral septum, hypothalamus, mammillary body, entire amygdala, hilus of the dentate gyrus, and substantia nigra. Chimpanzee OXTR/AVPR1a receptor distribution is compared to previous studies in several other primate species. One notable difference is the lack of OXTR in reward regions such as the ventral pallidum and nucleus accumbens in chimpanzees, whereas OXTR is found in these regions in humans. Our results suggest that in chimpanzees, like in most other anthropoid primates studied to date, OXTR has a more restricted distribution than AVPR1a, while in humans the reverse pattern has been reported. Altogether, our study provides a neuroanatomical basis for understanding the function of the oxytocin and vasopressin systems in chimpanzees.

DOI: 10.1007/s00429-021-02369-7
Alternate Journal: Brain Struct Funct