Prescription opiate use by adolescent females has increased dramatically in the past decade. This use is highly problematic, not only due to the risks of overdose and addiction, but also due to the potential neurodevelopmental effects these drugs may have during this sensitive period. In female populations, such developmental use may also significantly impact the reproductive axis given the role that endogenous opioids play in both sexual maturation and reproductive function. By altering neural and endocrine development, short-term opiate use during adolescence could trigger long-term modifications in the female, which are then transmitted to her future offspring even in the absence of continued use. Over the past few years, we have developed an animal model of adolescent morphine exposure in female rats to examine the long-term consequences of opiate use during this unique developmental period. These studies revealed significant modifications in both gene expression and behavior in the offspring (F1 generation) of morphine exposed females. These transgenerational effects occur in the absence of in utero exposure, as all of the adolescent morphine-exposed females are drug-free for at least 21 days prior to mating. Moreover, we have recently extended our observations to the F2 generation and continue to observe effects. The nature of these modifications suggests a phenotype that may be more vulnerable to substance abuse. Interestingly, many of these effects are sex-specific. The purpose of the present proposal is to characterize the abuse potential of this phenotype using drug self-administration. Thus, we aim to characterize morphine self-administration behavior including acquisition, maintenance and reinstatement (Specific Aim 1);and compare it to cocaine self-administration acquisition, maintenance, and reinstatement (Specific Aim 2). Finally, we aim to examine the impact of both environmental enrichment and stress on the expression of this phenotype (Specific Aim 3). Studies will determine the persistence of offspring effects in the F2 generation and, by examining both male and female offspring, will also determine whether observed transgenerational effects are sexually dimorphic. Moreover, by examining two distinct drugs of abuse, we can delineate differential patterns within the reward circuitry that will provid insight into the mechanism of action of the observed phenotype. Given the increased use of opiates in this population (both medical and non-medical), understanding the persistent developmental effects of these drugs will delineate potential risks associated with opiate use beyond the direct effects on the user. We view this work in the context of intergenerational, non-genomic transfer of substance use disorders.

Public Health Relevance

The use of prescription opiates in adolescent populations has increased dramatically in the past decade. We have observed significant multigenerational effects of female adolescent opiate exposure using a rat model. Delineating the impact of this exposure on next generation substance use vulnerability is highly relevant to human health, as these findings will enhance our understanding of the long-term impact of opiate use in this population.

National Institute of Health (NIH)
National Institute on Drug Abuse (NIDA)
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Biobehavioral Regulation, Learning and Ethology Study Section (BRLE)
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Satterlee, John S
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Tufts University
Veterinary Sciences
Schools of Veterinary Medicine
United States
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Byrnes, Elizabeth M; Vassoler, Fair M (2017) Modeling prenatal opioid exposure in animals: Current findings and future directions. Front Neuroendocrinol :
Vassoler, Fair M; Oliver, David J; Wyse, Cristina et al. (2017) Transgenerational attenuation of opioid self-administration as a consequence of adolescent morphine exposure. Neuropharmacology 113:271-280
Bodi, Caroline M; Vassoler, Fair M; Byrnes, Elizabeth M (2016) Adolescent experience affects postnatal ultrasonic vocalizations and gene expression in future offspring. Dev Psychobiol 58:714-23
Vassoler, Fair M; Wright, Siobhan J; Byrnes, Elizabeth M (2016) Exposure to opiates in female adolescents alters mu opiate receptor expression and increases the rewarding effects of morphine in future offspring. Neuropharmacology 103:112-21
Vassoler, F M; Byrnes, E M; Pierce, R C (2014) The impact of exposure to addictive drugs on future generations: Physiological and behavioral effects. Neuropharmacology 76 Pt B:269-75
Ravenelle, R; Santolucito, H B; Byrnes, E M et al. (2014) Housing environment modulates physiological and behavioral responses to anxiogenic stimuli in trait anxiety male rats. Neuroscience 270:76-87
Pierce, R Christopher; Vassoler, Fair M (2014) Reduced cocaine reinforcement in the male offspring of cocaine-experienced sires. Neuropsychopharmacology 39:238
Vassoler, Fair M; Johnson-Collins, Nicole L; Carini, Lindsay M et al. (2014) Next generation effects of female adolescent morphine exposure: sex-specific alterations in response to acute morphine emerge before puberty. Behav Pharmacol 25:173-81
Vassoler, Fair M; Johnson, Nicole L; Byrnes, Elizabeth M (2013) Female adolescent exposure to cannabinoids causes transgenerational effects on morphine sensitization in female offspring in the absence of in utero exposure. J Psychopharmacol 27:1015-22
Ravenelle, Rebecca; Byrnes, Elizabeth M; Byrnes, John J et al. (2013) Environmental enrichment effects on the neurobehavioral profile of selective outbred trait anxiety rats. Behav Brain Res 252:49-57

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