Navigation Links
Early isolation linked to enhanced response to cocaine
Date:4/17/2009

NEW ORLEANSDrug addiction affects millions of people around the world, causing numerous problems ranging from emotional and psychological difficulties to physical and health issues. Initial drug use can be motivated by curiosity or peer pressure, but in some animals, such as rats, it can also be the result of a stressful early life event, such as social isolation. A new study examines the impact of social isolation on the animal's response to cocaine.

The study, Social Isolation During Perinatal Development Alters the Behavioral Response to Cocaine in Juvenile Rats, was conducted by Natasha Lugo-Escobar, Nicole Carreras and Annabell C. Segarra, University of Puerto Rico, School of Medicine, Rio Piedras, PR. The team will present its findings at the 122nd Annual Meeting of the American Physiological Society (APS; www.the-aps.org/press), which is part of the Experimental Biology 2009 scientific conference. The meeting will be held April 18-22, 2009 in New Orleans.

The Study

Drugs of abuse act on the reward centers of the brain. These areas are normally involved in mediating pleasure, and also regulate the psycho-stimulant effects of drugs such as cocaine. Stress is known to enhance drug seeking behavior, as well as the psychostimulant effects of cocaine. Since rats are social animals, isolation was used as a stressor to explore the association between stress during development and susceptibility to the psychostimulant effects of drugs of abuse, such as cocaine.

Rats were stressed: (1) as fetuses (by housing the pregnant mother alone), (2) as neonates (by isolating newborn rats for 1 hr daily during the first 9 days of life) or as adolescents (by housing each rat separately during days 21-35). Two additional groups: (4) isolated as fetuses, neonates and adolescents and (5) controls - not isolated during any developmental period, comprised the 5 groups studied. When rats reached 21 days of age, they were weaned from their mothers and tested for the psychostimulant response to cocaine as well as for the development of sensitization, a phenomenon characterized by an increase response to the same amount of a drug over time. For 5 days, half of the rats from all groups were injected with saline and the other half with cocaine (15 mg/kg). This was followed by a 7 day drug free period and an additional cocaine injection on day 13. Locomotor activity was measured on days 1, 5 and 13 immediately after injection.

Results

The researchers found that:

  • Rats that were isolated during all three developmental periods, showed a higher locomotor response to cocaine than control rats.
  • The study indicates that the developmental period most susceptible to isolation stress, particularly in males, is the neonatal period, since males isolated as neonates show an increase in the locomotor, and sensitized response to cocaine, compared to male control and to female rats.

Conclusions

This study suggests that isolation during early development alters the brain sensitivity to cocaine, such that when the animal reaches adolescence and is exposed to cocaine, it is more sensitive to the psychostimulant effects of the drug.

These studies contribute to understanding the mechanisms that may lead to greater abuse of drugs during adolescence.

Additional studies are planned.


'/>"/>

Contact: Donna Krupa
dkrupa@the-aps.org
703-967-2751
American Physiological Society
Source:Eurekalert

Related biology news :

1. 60 second test could help early diagnosis of common brain diseases
2. Restless legs syndrome affects nearly 2 percent of US/UK children
3. Bleeding, not inflammation, is major cause of early lung infection death
4. Pig study sheds new light on the colonisation of Europe by early farmers
5. Color contrast is seen by the brain early doors
6. Extra gene copies were enough to make early humans mouths water
7. Was ability to run early mans Achilles heel?
8. New technique can be breakthrough for early cancer diagnosis
9. Yam bean a nearly forgotten crop
10. NIH awards nearly $23M to University of Chicago for translational research
11. Yam bean a nearly forgotten crop
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/5/2017)... 5, 2017 Today HYPR Corp. , ... server component of the HYPR platform is officially ... end-to-end security architecture that empowers biometric authentication across Fortune ... already secured over 15 million users across the financial ... connected home product suites and physical access represent a ...
(Date:3/30/2017)... -- The research team of The Hong Kong Polytechnic ... by adopting ground breaking 3D fingerprint minutiae recovery and matching technology, ... accuracy for use in identification, crime investigation, immigration control, security of ... ... A research team led by Dr ...
(Date:3/24/2017)... The Controller General of Immigration from Maldives Mr. Mohamed Anwar ... prestigious international IAIR Award for the most innovative high security ePassport and ... ... Maldives Immigration Controller General, Mr. Mohamed ... the right) have received the IAIR award for the "Most innovative high ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... ... October 12, 2017 , ... They call it the ... network, a depiction of a system of linkages and connections so complex and ... professor of computer science at Worcester Polytechnic Institute (WPI) and director of the ...
(Date:10/12/2017)... ... October 12, 2017 , ... ... the pharmaceutical and biotechnology industries to improve patient outcomes and quality of life, ... in analytical testing are being attributed to new regulatory requirements for all new ...
(Date:10/11/2017)... ... October 11, 2017 , ... ComplianceOnline’s Medical Device Summit ... 7th and 8th June 2018 in San Francisco, CA. The Summit brings together current ... several distinguished CEOs, board directors and government officials from around the world to address ...
(Date:10/11/2017)... ... October 11, 2017 , ... A new study ... in frozen and fresh in vitro fertilization (IVF) transfer cycles. The ... IVF success. , After comparing the results from the fresh and frozen transfer ...
Breaking Biology Technology: