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Biomedical subjects

C L Coe

Publications and source records attributed to C L Coe.

At least 73 records · Page 4Linked to original sources
PubMed1983

Behavioral, but not physiological, adaptation to repeated separation in mother and infant primates.

Mother and infant squirrel monkeys were subjected to a series of brief separations in order to evaluate how behavioral and physiological responses change following multiple exposures to stress. Beginning when the infants reached three months of age, their behavioral and hormonal responses were assessed during six 1-hr separations; and additional five dyads served as controls for the effect of repeated disturbance. The separated infants showed a marked and progressive decrease in distress calling across time, but no change was observed in the high levels of agitated activity or the plasma cortisol response to separation. This finding questions the traditional use of distress vocalizations as a measure of stress and indicates that certain types of behavior can change independently of physiological arousal responses, which may continue to occur even after repeated exposures to stress.

Adaptation, Psychological↗
PubMed1983

Adrenal responses to reinforcement and extinction: role of expectancy versus instrumental responding.

Plasma corticosterone levels were evaluated during operant conditioning in order to determine the effect of reinforced and nonreinforced responding (extinction) on adrenal activation. The influence of instrumental responding was assessed by comparing trained rats with yoked subjects that received a matched reward schedule in the absence of an operant task. Reinforcement sessions resulted in a significant decrease in adrenal secretion at 20 min, but not at 5 min, whereas extinction caused a rapid increase in corticosterone levels at 5 min and an even greater elevation by 20 min. Comparison of the operant and yoked subjects showed that this effect of reinforcement and extinction was not dependent on instrumental responding, but rather on the receipt or withdrawal of the expected reward.

Animals↗
PubMed1982

Hormonal responses accompanying fear and agitation in the squirrel monkey.

The adrenocortical and gonadal responses of 14 male monkeys were evaluated during four experimental conditions in order to evaluate the influence of social interactions on endocrine responsiveness. Plasma hormone levels were determined during the establishment of social relations, after 60-min exposures to a novel environment, after 60-min exposures to a snake, and 60 min after ACTH administration. Both adrenal and gonadal secretion changed significantly during the first day after social relations were established, although only dominant males showed increases in testosterone, whereas cortisol levels rose in all subjects. Increases in cortisol, but not testosterone, were also observed following exposure to novelty or a snake. The presence of a social partner reduced signs of behavioral disturbance during these test conditions, although the adrenal responses were equivalent or greater than when tested alone. This finding qualifies earlier research which indicated that social support was beneficial for reducing stress when squirrel monkeys were tested in larger groups in their home environment.

Adrenocorticotropic Hormone↗
PubMed1982

Cortisol responses under different housing conditions in female squirrel monkeys.

Adult female squirrel monkeys were housed in a group, in pairs or individually. Plasma levels of cortisol obtained under basal and stress conditions once weekly for four weeks were significantly lower in pair-housed females than in those living in a social group or individually. The increment in cortisol levels after stress (induced by handling and ether anesthesia) also was smaller in females housed in pairs. The cortisol values of the pair-housed females were positively correlated with those of their partners. Basal cortisol levels in the group-living females showed a significant rank-order correlation with dominance status. This indicated that social interactions in group-living animals can influence cortisol levels in a complex manner, either increasing or decreasing them. The relatively lower pituitary--adrenal activation when a single partner was present also indicated that the social environment can affect an individual's general level of arousal and subsequently alter the response to stressful stimuli.

Animals↗
PubMed1978

Hormonal response to stress in the squirrel monkey (Saimiri sciureus).

The pituitary-adrenal and gonadal responses following stress were evaluated in the squirrel monkey. Plasma levels of cortisol (CS), ACTH and testosterone (T) were determined during a 4-h period following the combined stress of capture and ether anesthesia. The results indicated that the squirrel monkey manifests higher basal levels of steroids than typically found in other mammals. The endocrine response following stress was biphasic, involving an initial elevation and subsequent decline in hormone levels. Males manifested significantly higher plasma levels of CS and T and lower plasma levels of ACTH than did females.

Adrenal Glands↗
PubMed1978

Annual reproductive strategy of the squirrel monkey (Saimiri sciureus).

The physiological and behavioral factors underlying the annual reproductive cycle of the squirrel monkey were evaluated under controlled laboratory conditions. Mating activity following the formation of two social groups served to synchronize the reproductive phases during the subsequent year of observation. Changes in male and female reproductive status were assessed during four designated phases: breeding, pregnancy, lactation and fatting. Behavioral and somatic changes in gonadectomized subjects, living in the social groups, were also evaluated. The variations in behavior and physiology across the year were considered in terms of factors constraining the timing of the natural reproductive pattern.

Animals↗
PubMedDate not supplied

Risk factors for endometriosis in the rhesus monkey (Macaca mulatta): a case-control study.

The autopsy records between 1980 and 1995 of 399 female rhesus monkeys (Macaca mulatta) at the Wisconsin Regional Primate Research Center were examined. Spontaneous endometriosis was found in 81 (20%) of the animals. The mean (+/- SD) ages at death for animals with and without endometriosis were 20.7 +/- 5.5 (range 10-35) and 13.4 +/- 7.7 (range 4-37) years respectively. Many of the animals had been exposed to experimental procedures, including laparoscopies, hysterotomies and oestradiol implants, and these were examined as possible risk factors for endometriosis. Of the 81 affected animals, 62 were matched to unaffected controls for age at death (to within 1 year) and year of death (to within 2 years) and the effect of various factors on the development of endometriosis was determined using conditional logistic regression. Exposure to three or more oestradiol implants or one or more hysterotomies were both significant risk factors, with estimated relative risks of 9.7 (95% confidence interval 2.5-37.2) and 5.8 (95% confidence interval 1.6-20.2) respectively. Animals that had been exposed to one or more laparoscopies showed no increased risk for developing endometriosis. These findings provide insight into the aetiology of the disease in women. ?2P51 4RR00167

Aging↗