Related Experiment Video
Updated: Jul 13, 2026
09:12
The Resident-intruder Paradigm: A Standardized Test for Aggression, Violence and Social Stress
Published on: July 4, 2013
Photoperiod affects estrogen receptor alpha, estrogen receptor beta and aggressive behavior
Brian C Trainor1, Michael R Rowland, Randy J Nelson
1Department of Psychology, Institute for Behavioral Medicine Research, Ohio State University, Columbus, OH 43210, USA. bctrainor@ucdavis.edu
The European Journal of Neuroscience
|July 7, 2007
Summary
Photoperiod influences aggressive behavior in Peromyscus mice by altering estrogen receptor (ERalpha and ERbeta) expression in key brain regions. Short days increase aggression and ERalpha, while decreasing ERbeta in the BNST.
Area of Science:
- Neuroendocrinology
- Behavioral Neuroscience
- Animal Behavior
Background:
- Estrogens significantly impact social behaviors in both sexes.
- Estrogen receptor subtypes (ERalpha and ERbeta) are crucial, but their response to environmental cues is understudied.
- Photoperiod is a key environmental stimulus for seasonal breeders, signaling resource availability.
Purpose of the Study:
- To investigate the influence of photoperiod on aggressive behavior in Peromyscus mice.
- To characterize the effects of photoperiod on the expression of ERalpha and ERbeta in specific brain regions.
Main Methods:
- Immunocytochemistry to visualize ERalpha and ERbeta protein expression.
- Real-time polymerase chain reaction (PCR) to quantify ERalpha and ERbeta mRNA levels.
- Behavioral assays to measure aggressive behavior in two Peromyscus species under different photoperiods.
Main Results:
- Both Peromyscus species exhibited increased aggression in short days compared to long days.
- Short days led to increased ERalpha staining in the posterior bed nucleus of the stria terminalis (BNST) in both species.
- Short days reduced ERbeta staining in the posterior BNST and increased it in the medial amygdala for both species.
- Real-time PCR confirmed increased ERalpha mRNA and decreased ERbeta mRNA in the BNST region under short days.
Conclusions:
- Photoperiod significantly modulates aggressive behavior in Peromyscus mice.
- Changes in photoperiod alter the expression of ERalpha and ERbeta in brain regions associated with social behavior.
- These photoperiod-induced changes in estrogen receptor expression likely mediate the observed behavioral effects.
Related Concept Videos
02:27Background and Environment Affect Phenotype
Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
01:28Causes of Social Behavior III: Biological and Environmental Influences
Social behavior is a complex phenomenon that arises from the interaction between biological predispositions and environmental influences. This intricate interplay shapes how individuals think, feel, and act in various social contexts. Understanding these mechanisms requires insights from psychology, neuroscience, genetics, and evolutionary theory.Environmental Influences on Social BehaviorEnvironmental factors, including temperature, odors, and visual stimuli, play a crucial role in shaping...
01:28Menopause
Menopause, a natural biological process marking the end of a woman's fertility, typically occurs between the fifth and sixth decade of life. This phase is characterized by the exhaustion of the ovarian follicle pool, leading to less responsive ovaries despite the high levels of Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH). The consequential decrease in estrogen production results in symptoms like hot flashes, heavy sweating, headaches, hair loss, muscle pains, vaginal...
01:22Hormonal Regulation of the Menstrual Cycle
The ovarian cycle regulates endometrial changes throughout a single menstrual cycle via the coordinated action of gonadotrophin-releasing hormone (GnRH) and gonadotrophins.
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.