Sad Simians (Depressed to Death)

We've all heard the cliche about dying from a broken heart. For some monkeys, it's not a cliche at all. It's the result of a lifetime of suffering in captivity - isolated from friends and family and surrounded by individuals who are enemies who cause fear, pain distress and suffering. Others don't appear to care one way or the other. Some of those individuals are other monkeys - and some of them are the humans involved in the experiments.


Citation:
Shively, C. A., Register, T. C., Friedman, D. P., Morgan,T. M., Thompson,J., and Lanier, T. (2005). Social stress-associated depression in adult female cynomolgus monkeys (Macaca fascicularis). Biol Psychol 69:67-84.

Summary of experiment:
Female monkeys were put into unnatural social groups intended to induce extreme depression in some animals. The social stress was devastating.

"Over the course of the experiment, 56% of the monkeys in the highest quartile of depression died (5/9), whereas there were only one (11%) or two (22%) deaths in each of the other quartiles. Thus, behavioral depression was associated with increased mortality..."

*Only one or two deaths*? In a setting where proper nutrition is supposedly provided, there are no predators or natural disasters, and veterinary care is readily available, what could the mortality rate be? Apparently there are some very serious risks for morbidity and mortality in this lab.


Institutional affiliations:
Wake Forest University School of Medicine

Funded by:
National Institute of Mental Health
National Institute of General Medical Sciences
John D. and Catherine T. MacArthur Foundation

Speed kills (brain cells and monkeys)

Maryland, USA

People take prescription stimulants for ADHD. This article reported results from experiments on monkeys to see if normal clinical doses of a prescription stimulant caused brain damage in NHPs after 4 weeks of use. The authors write about two baboon experiments and one experiment on wild caught squirrel monkeys.

Citation: Ricaurte, G. A., Mechan, A. O., Yuan, J., Hatzidimitriou, G., Xie, T., Mayne, A. H., and McCann, U. D. (2005). Amphetamine treatment similar to that used in the treatment of adult attention-deficit/hyperactivity disorder damages dopaminergic nerve endings in the striatum of adult nonhuman primates. J Pharmacol Exp Ther 315:91-8.

Summary of Experiment:
These authors don’t report the number of monkeys clearly in their methods section. My best effort to understand how many animals were used from the captions to their figures are that there were 9 baboons and 9 squirrel monkeys…but the ambiguity means this is a minimum # of animals and there may have been more.

All animals were killed after about 4 weeks of drug administration. The brains of amphetamine-treated animals differed from controls. Based on the damage done to the brains of animals given the drug, the authors concluded that clinical doses of stimulants were neurotoxic and they called for more controlled studies.

Author affiliation: Department of Neurology, Johns Hopkins Medical Institutions, 5501 Hopkins Bayview Circle, Rm. 5B.71E, Baltimore, MD 21224, USA.

Funding acknowledged: United States Public Health Service Grants DA13946, DA017964, and HD050202

Begin the Beguine

Fitting that I am writing my very first post wearing my brand new monkey-themed pajamas.

All manner of monkey business to follow.