Thomas P. Gordon

Consequences of social conflict on plasma testosterone levels in rhesus monkeys.

&NA; Four adult male rhesus monkeys formed a new social group with 13 adult females. The male who became dominant [alpha] showed a progressive increase in plasma testosterone. The male who became subordinate to the other three males showed an 80% fall in testosterone from baseline levels. After 7 weeks, this group was introduced to a well‐established breeding group, and all four males became subordinate to all members of the breeding group. All four males evidenced a fall in testosterone during the first week after introduction, and within 6 weeks their levels were approximately—80% of pre‐introduction values. The alpha male of the breeding group showed a large increase in testosterone [238%] 24 hr after he successfully defended his group and became the dominant animal of the larger, newly‐formed group. Thus, plasma testosterone levels appear to be significantly influenced by the outcome of conflict attendant to alterations in status of rhesus monkeys living in social groups.

Timing of births and reproductive success in rhesus monkey social groups.

Analysis of six years of birth records (228 potential reproductive years) from 71 female rhesus monkeys, housed in social groups in outdoor compounds, revealed several variables which influenced the reproductive pattern. The timing of conception in this seasonally breeding species was influenced by age, parity, and reproductive outcome the previous year, but not by social rank. In contrast, high social rank did confer an advantage in higher conception and lower infant mortality rates.

Aggression and social controls in rhesus monkey (Macaca mulatta) groups revealed in group formation studies.

Agonistic responses were the primary form of social interaction during five rhesus group formations. Males showed the most extreme forms of aggression initially, but as formative processes progressed, females became more active and aggression less severe. Initial agonistic interactions serve to establish the social order of an emerging group. As a group becomes organized, extreme forms of aggression disappear and aggressive frequencies decline.

Changes in testosterone and behavior during adolescence in the male rhesus monkey.

&NA; Five adolescent male rhesus were followed for 3 years, from age 2 through age 4, with the collection of monthly testosterone levels, along with observation of behavior. Testosterone levels showed initial rises by age 3, but did not show the adult male seasonal pattern until 4. Play behavior fell significantly from age 2 to age 3, while sex behavior showed seasonal increases in both Year 2 and Year prior to the rise in plasma testosterone. The number of adult males in the social group may influence the timing of the rise in testosterone during adolescence. Injury may also serve to delay the increase in testosterone in males during their third year of development.

Effects of Increased Testosterone Secretion on the Behavior of Adult Male Rhesus Living in a Social Group

Selected members of an all-male social group of rhesus monkeys were treated with twice-weekly injections of human chorionic gonadotropin (HCG) to determine the effects of the consequently increased androgen secretion on social behavior. Radioimmunoassay of blood samples confirmed significant increases in serum testosterone levels in each of 4 subject, but only 3 of these showed significant behavioral changes. The basic social structure of the group, including the dominance hierarchy, was not disrupted by the treatment with HCG. Rather, the behavioral changes which did not occur appeared to be intensifications of previously existing social relationship.

Urinary 17-OHCS response of high- and low-aggressive rhesus monkeys to shock avoidance.

Abstract This two-part study was designed to explore the hypothesis that a rhesus monkeys aggressive behavior may be predictive of his adrenal cortical response to shock avoidance. In Part I, the relative aggressiveness of the animals was estimated and they were exposed to four weeks of free operant avoidance. Urinary 17-OHCS output was used as a measure of stress. The results show that the high-aggressive monkeys are chronically stressed and take longer to learn the task. The low-aggressive animals show little stress response and learn the task quickly. In Part II the avoidance paradigm was altered in order to study the possible confounding effects of two variables: initial training time and physiological lability. The results show that the difference in 17-OHCS levels between the two groups is chronic and stable and is not necessarily a function of either of these extraneous variables. The stable differences in 17-OHCS output were interpreted as being a function of the interaction of a particular type of subject and a particular type of task.

Late diagnosis of Cushing’s disease in a child: what lessons can be learned?1)

Abstract We present a case of late diagnosis of an adolescent female with Cushing’s disease or excess glucocorticoid secretion due to the presence of an adrenocorticotropic hormone (ACTH) secreting tumor on the pituitary. Her main complaints at first presentation in 2008 were short stature and weight gain. Although these are the main criteria for testing for Cushing’s syndrome outlined by the 2008 Endocrine Society guidelines, they were not enough to lead to a timely diagnosis. The reasons may include the endocrinologists believing that additional more common symptoms needed to be present to test for Cushing’s syndrome. Consequently, the guidelines were not followed leading to placing the child on growth hormone (GH) with no further evaluation until well after 1 year of minimal growth. While Cushing’s syndrome is rare in children and hard to diagnose, a more collaborative effort among pediatricians, endocrinologists, radiologists, surgeons, as well as parents, is required to diagnose and help cure children with this disease.