Author : Jing Jiang
Publisher :
ISBN 13 : 9781321362923
Total Pages : pages
Book Rating : 4.3/5 (629 download)
Book Synopsis Experimental Studies of the Behavior and Physiology of Rhesus Macaques (Macaca Mulatta) Due to Ancestry Background, Methamphetamine Treatment and Social Stress by : Jing Jiang
Download or read book Experimental Studies of the Behavior and Physiology of Rhesus Macaques (Macaca Mulatta) Due to Ancestry Background, Methamphetamine Treatment and Social Stress written by Jing Jiang and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Rhesus macaques are the most widely-used nonhuman primate species for biomedical research in the U.S.; consequently a detailed understanding of their behavior is critical. India and China are two major countries of origins of rhesus macaques currently in the U.S. Anecdotal reports and a study with a limited number of animals suggested that Chinese-origin rhesus monkeys differ in physiology and behavior from those of Indian-origin. However, no studies have examined the effects of varying degrees of Chinese ancestry (DCA) on behavior using a large sample. In Chapter One I use behavioral data from a colony-wide program to examine the relation of DCA to behavior, emotionality, and activity. The 249 subjects, born and reared in an outdoor social environment, were separated from their groups for a 25-hr indoor testing period. Their DCA (range: 0.6 to 99.4%) was determined by analyzing the frequency of short tandem repeat alleles. I found that DCA had the largest effect on fearfulness, with the more hybridized animals being the least fearful and the more pure Indian- and Chinese-origin macaques resembling each other. Rhesus macaques are widely used as a biomedical model for research on drug addiction. It is estimated by the United Nations Office for Drug Control that amphetamine-type pscyhostimulants are used by 33 million people globally, second only to cannabis use, and equals opiate and cocaine use combined. Methamphetamine (Meth) abuse has a number of negative psychological and behavioral consequences. Previous research on animals with single or multiple high dose (eg. 40 mg/kg) administrations demonstrated behavioral deficits involving conditioning and learning. However, little research has examined the effects of Meth on spontaneous behaviors under a dosing pattern closer to human Meth use. In Chapter Two I studied 22 adult male rhesus macaques to examine the effects of Meth on spontaneous behaviors. Twelve of the 22 subjects were injected intramuscularly with Meth on weekdays with an escalating dosing regimen starting from 0.1mg/kg and ending with 0.75mg/kg at the end of a four-week period. Ten controls received saline. I recorded behaviors in three settings: the animals' home cages, during a Human Intruder test, and during a Novel Object test. Behaviors measured reflected the domains of activity, abnormal behavior expression, emotionality, curiosity, and impulsivity. Compared with controls, I found that Meth animals were more active in the home cage observations and in the Novel Object test, showed more abnormal behaviors in the home cage observations and Novel Object test, were more emotionally reactive in the Human Intruder and the Novel Object tests, and were more curious in all three tests. No difference was found in impulsivity between the two groups. Growing evidence has suggested that central nervous system (CNS) complications in humans infected with HIV have been increasing in prevalence, and these complications seem to be exacerbated by drugs of abuse. Interruptions in the blood-brain barrier (BBB), the micro-blood vessels in the brain, have been shown to be associated with these CNS complications. Both psychosocial stress, prevalent among HIV-positive individuals, and Meth abuse have been shown independently to disrupt the BBB. While Meth abuse has become a leading factor for human immunodeficiency virus (HIV) transmission among certain populations, no study has looked at the combined effects of Meth and social stress on the BBB for these populations. In Chapter Three, I try to understand how psychosocial stress and Meth abuse, together and alone, may affect the BBB integrity during immunodeficiency virus infection by studying 21 adult male rhesus macaques infected with Simian immunodeficiency virus (SIV). A 2 by 2 factorial design was used. Psychosocial stress was manipulated by using a previously-published socialization paradigm. Eleven out of 21 adult male rhesus macaques were placed in the unstable socialization group with high levels of stress; ten animals were place in the stable socialization group with low levels of stress. Eleven animals (five from the stable group and six from the unstable group) were injected intramuscularly with Meth on weekdays with an escalating dosing regimen starting from 0.1mg/kg and ending with 0.75mg/kg at the end of a four-week period. Subsequently these animals were given 0.75mg/kg of Meth twice daily on weekdays throughout the rest of the study. The remaining ten received the same amount of saline. At the end of the four-week period all the animals were inoculated with SIVmac251. During the course of the study, cerebrospinal fluid (CSF)/serum albumin ratio was sampled five times: 1) Immediately before drug treatment, 2) immediately before inoculation of SIV, 3) two weeks post inoculation, 4) ten weeks post inoculation, 5) at necropsy. Immunohistochemical staining was also performed on the brain slices of all the subjects to detect ZO-1, a molecular marker for BBB integrity. Three brain regions were examined: caudate, putamen, and nucleus accumbens. Surprisingly, no effects were found for methamphetamine; rather social condition impacted BBB integrity, with animals in the unstable group showing a greater proportion of disrupted brain vessels in the nucleus accumbens compared to animals in stable social groups.
