Alternate NameT4
OrganismRattus norvegicus
Aging PhenotypeLife-span extension
Allele TypeN/A
DescriptionMale Wistar rats made hypothyroidic by intraperitoneal thyroxine (T4) injection during the first 10 days of neonatal life had a life-span extended by approximately 4 months relative to controls (Ooka et al., 1983). The life extension effect of hypothyroidism was observed also in females, although the difference was smaller than that in males.
Gene FunctionNeonatal treatment with thyroxine induces hypothyroidism.
Other PhenotypesThe T4 levels of thyroxine treated rats are about two-thirds of control values up to 20 months of age. T3 level is low only at a young age. TSH level shows no significant difference from control, but is about half that of control after the stimulation of secretion by 6-propyl-2-thiouracil. The level of prolactin is much higher in the T4-treated group than in controls (Ooka et al., 1983).
Primary ReferenceOoka, H., Fujita, S., and Yoshimoto, E. (1983). Pituitary-thyroid activity and longevity in neonatally thyroxine-treated rats. Mech Ageing Dev 22, 113-20. [Abstract]
Other References
Relevant Links
Keywordshormonal, signaling, rat