Sedative And Analgesic Drugs Can Have Profound Negative Effects On Young Brains, Mouse Study Suggests

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Sedative And Analgesic Drugs Can Have Profound Negative Effects On Young

Brains, Mouse Study Suggests

ScienceDaily (Dec. 18, 2008) — A

large proteomics study on the brains of newborn mice provides more evidence

that numbing drugs often used in obstetric or pediatric medicine can have

profound and long-term negative effects, even after minimal exposure.

This study highlights the delicate state of the developing nervous system

and reinforces the use of caution when administering sedatives, anesthetics,

and anti-convulsants to pregnant women or infants.

Compounds that either block excitatory NMDA receptors or activate inhibitory

GABA receptors in the brain are clinically useful as anesthetics or for

treating disorders like seizures and insomnia. However, just like other

chemicals that produce similar mind-soothing effects (e.g. alcohol), excessive

use can be detrimental –particularly in still-developing individuals.

To examine how far-reaching the physiologic effects of such 'numbing' drugs

(sedatives, hypnotics, analgesics) are, Kaindl and colleagues treated

6-day old mice with two doses of either the NMDA receptor blocker dizocilpine

or the GABA receptor activator Phenobarbital and then analyzed subsequent

changes in brain protein expression.

They observed both acute and sustained effects, with protein changes in the

cerebral cortex (the area controlling memory, thought, awareness, and language)

evident after just 24 hours, and these changes were still present one week and

one month after the one-day drug treatment. The affected proteins are involved

in crucial processes like cell growth, cell death, and the formation of neural

circuits (In another recent study, the authors were able to confirm that such

drug treatment negatively influences learning and memory).

A similar drug dose given to adult mice did not produce such changes, which

the authors note clearly shows how susceptible infant brains are compared to

adults. Importantly, this study shows that drug overuse on even one occasion

(for example, during the delivery procedure) can have long-term implications.

Journal reference:

1.

Kaindl et al. Brief

Alteration of NMDA or GABAA Receptor-mediated Neurotransmission Has Long Term

Effects on the Developing Cerebral Cortex. Molecular & Cellular Proteomics,

2008; 7 (12): 2293 DOI: 10.1074/mcp.M800030-MCP200

Adapted

from materials provided by American

Society for Biochemistry and Molecular Biology, via EurekAlert!, a service of

AAAS.

http://www.sciencedaily.com/releases/2008/12/081211141936.htm