Hormonal correlates of the annual cycle of activity and body temperature in the South-American tegu lizard (Salvator merianae)

Autor(es)

Zena, Lucas A. ^{[1, 2]} ; Dillon, Danielle ^[2] ; Hunt, Kathleen E. ^[3] ; Navas, Carlos A. ^[1] ; Buck, C. Loren ^[2] ; Bicego, Kenia C. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biosci, Dept Physiol, BR-05508090 Sao Paulo, SP - Brazil

^[2] No Arizona Univ, Dept Biol Sci, Box 5640, Flagstaff, AZ 86011 - USA

^[3] George Mason Univ, Dept Biol, Fairfax, VA 22030 - USA

^[4] Sao Paulo State Univ, Coll Agr & Vet Sci, Dept Anim Morphol & Physiol, BR-14884900 Jaboticabal, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: General and Comparative Endocrinology; v. 285, JAN 1 2020.
• Citações Web of Science: 0

Resumo

Life history transitions and hormones are known to interact and influence many aspects of animal physiology and behavior. The South-American tegu lizard (Salvator merianae) exhibits a profound seasonal shift in metabolism and body temperature, characterized by high daily activity during warmer months, including reproductive endothermy in spring, and metabolic suppression during hibernation in winter. This makes S. merianae an interesting subject for studies of interrelationships between endocrinology and seasonal changes in physiology/behavior. We investigated how plasma concentrations of hormones involved in regulation of energy metabolism (thyroid hormones T-4 and T-3; corticosterone) and reproduction (testosterone in males and estrogen/progesterone in females) correlate with activity and body temperature (Tb) across the annual cycle of captive held S. merianae in semi-natural conditions. In our initial model, thyroid hormones and corticosterone showed a positive relationship with activity and Tb with independent of sex: T-3 positively correlated with activity and Tb, while T-4 and corticosterone correlated positively with changes in Tb only. This suggests that thyroid hormones and glucocorticoids may be involved in metabolic transitions of annual cycle events. When accounting for sex-steroid hormones, our sex separated models showed a positive relationship between testosterone and Tb in males and progesterone and activity in females. Coupling seasonal endocrine measures with activity and Tb may expand our understanding of the relationship between animal's physiology and its environment. Manipulative experiments are required in order to unveil the directionality of influences existing among abiotic factors and the hormonal signaling of annual cyclicity in physiology/behavior. (AU)

• Processo FAPESP: 15/04849-6 - Participação dos canais TRPV4 na termorregulação de endotermos
• Beneficiário: Kênia Cardoso Bícego
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/06192-2 - Fisiologia sazonal no lagarto teiú Salvator merianae: um modelo animal para avaliar funções fisiológicas em ambientes dinâmicos e em constante alteração
• Beneficiário: Lucas Aparecido Zena
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado
• Processo FAPESP: 14/16320-7 - Impactos das mudanças climáticas e ambientais sobre a fauna: uma abordagem integrativa
• Beneficiário: Carlos Arturo Navas Iannini
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático
• Processo FAPESP: 17/01652-2 - Fisiologia sazonal no lagarto teiú Salvator merianae: um modelo animal para avaliar funções fisiológicas em ambientes dinâmicos e em constante alteração
• Beneficiário: Lucas Aparecido Zena
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado