title: Reappearance of thymus of ageing rats after orchidectomy.
abstract: There was no visible thymus in ageing rats of 18 months, and 7 days after orchidectomy there was still no evidence of a thymus. By 30 days after the operation, however, there was a well-defined and well developed bilobular thymus overlying the heart, although it was smaller than those observed in 10-week-old rats. Histologically, the tissue appeared normal, was well vascularized, filled with lymphocytes and several mitotic figures were also seen. When compared with sham-operated animals, blood from these animals had a significantly higher lymphocyte count. These results have important implications for the possible enhancement of the immune system with associated improvement of health during ageing.
mesh_terms: D000375:Aging; D000818:Animals; D007958:Leukocyte Count; D008297:Male; D009919:Orchiectomy; D009929:Organ Size; D051381:Rats; D011919:Rats, Inbred Strains; D012038:Regeneration; D013739:Testosterone / Q000097:blood; D013950:Thymus Gland / Q000033:anatomy & histology / Q000502:physiology*
chemical_list: D013739:Testosterone