title: Long-term effects of castration on the skeleton of male rhesus monkeys (Macaca mulatta).
abstract: While osteopenia (OPE) and osteoporosis (OPO) have been studied in various species of aging nonhuman primates and extensively in ovariectomized rhesus and cynomolgus macaques, there is virtually no information on the effects of castration on the skeleton of male nonhuman primates. Most information on castrated male primates comes from a few studies on the skeletons of eunuchs. This report used a subset of the Caribbean Primate Research Center's (CPRC) Cayo Santiago (CS) rhesus macaque skeletal collection to qualitatively and quantitatively compare the bone mineral density (BMD) of castrated and age-matched intact males and, thereby, determine the long-term effects of castration (orchidectomy) on bone. Lumbar vertebrae, femora, and crania were evaluated using dual-energy X-ray absorptiometry (DEXA or DXA) and digital radiography augmented, when fresh tissues were available, with autoradiography and histology. Results confirmed physical examinations of long bones that castration causes changes in the skeleton of male rhesus macaques similar to those found in eunuchs, including OPE and OPO of the vertebrae and femora, thinning of the skull, and vertebral fractures and kyphosis of the spine more severe than that caused by normal aging alone. Also like eunuchs, some castrated CS male rhesus monkeys had a longer life span than intact males or females. Based on these results and the effects of castration on other tissues and organs of eunuchs, on behavior, hormone profiles and possibly on cognition and visual perception of human and nonhuman primates, and other mammals, castrated male rhesus macaques should be used with caution for laboratory studies and should be considered a separate category from intact males. Despite these caveats, the castrated male rhesus macaque should make an excellent animal model in which to test hormone replacement therapies for boys and men orchidectomized for testicular and prostate cancer.
authors.affiliation: Office of Laboratory Animal Resources, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia.|Caribbean Primate Research Center, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Kessler
authors.affiliation: Department of Biomedical Sciences, Texas A&M University, Baylor College of Dentistry, Dallas, Texas.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital Joseph and Wolf Lebovic Health Complex, Toronto, Ontario, Canada.
authors.forename: Antonietta M
authors.initials: AM
authors.lastname: Cerroni
authors.affiliation: Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital Joseph and Wolf Lebovic Health Complex, Toronto, Ontario, Canada.
authors.forename: Marc D
authors.initials: MD
authors.lastname: Grynpas
authors.affiliation: Caribbean Primate Research Center, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico.
authors.forename: Olga D
authors.initials: OD
authors.lastname: Gonzalez Velez
authors.affiliation: Caribbean Primate Research Center, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico.
authors.forename: Richard G
authors.initials: RG
authors.lastname: Rawlins
authors.affiliation: Yerkes National Primate Research Center, Emory University, Atlanta, Georgia.
authors.forename: Kelly F
authors.initials: KF
authors.lastname: Ethun
authors.affiliation: Office of Laboratory Animal Resources, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia.
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Wimsatt
authors.affiliation: Caribbean Primate Research Center, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico.
authors.forename: Terry B
authors.initials: TB
authors.lastname: Kensler
authors.affiliation: Department of Laboratory Medicine & Pathobiology, University of Toronto, Mount Sinai Hospital Joseph and Wolf Lebovic Health Complex, Toronto, Ontario, Canada.
authors.forename: Kenneth P H
authors.initials: KP
authors.lastname: Pritzker
mesh_terms: D015502:Absorptiometry, Photon / Q000662:veterinary; D000818:Animals; D001345:Autoradiography / Q000662:veterinary; D015519:Bone Density; D005269:Femur / Q000502:physiology*; D008159:Lumbar Vertebrae / Q000502:physiology*; D008253:Macaca mulatta / Q000502:physiology*; D008297:Male; D009919:Orchiectomy / Q000662:veterinary*; D011647:Puerto Rico; D011856:Radiographic Image Enhancement; D012886:Skull / Q000502:physiology*
keywords: Cayo Santiago; aging; bone density; longevity; orchidectomy; osteopenia; osteoporosis