Dopamine D2 receptors act upstream of AVP in the latero-anterior hypothalamus to modulate adolescent anabolic/androgenic steroid-induced aggression in Syrian hamsters

The Chinese medicinal herbs of spleen-meridian property regulate body temperature in yeast-induced fever rats

BACKGROUND

According to traditional Chinese medicine (TCM) theory, the herbal property is the most important guiding principle of ancient medication in China. The classification of warm- and cold-stimulating TCM is defined mainly based on the effects of herbs in regulating body temperature; however, the underlying mechanism of such distinction has not been fully identified.

METHODS

Here, four commonly used spleen-meridian herbs, Ginseng Radix and Astragali Radix as typical warm-stimulating herbs, and Nelumbinis Semen and Coicis Semen as typical cold-stimulating herbs, were selected to test their effects in regulating body temperature, as well as its triggered thermo-regulatory factors and energy related metabolites, in yeast-induced fever rats.

RESULTS

The intake of Astragali Radix increased body temperature in yeast-induced fever rats; while Coicis Semen showed cooling effects in such rats. In parallel, the levels of cAMP, PGE₂ and thermo-related metabolites, including choline, creatine, alanine, lactate and leucine, in the blood of yeast-induced rats were increased significantly by the intake of Astragali Radix. Oppositely, the cold-stimulating herbs, Nelumbinis Semen and Coicis Semen, showed cooling effects by increasing certain metabolites, e.g. histidine, tyrosine, lipid, myo-inositol, as well as AVP level.

CONCLUSION

Here, we compared different effects of warm and cooling spleen-meridian herbs in the regulation of body temperature. By providing an intuitive comparison of thermo-regulatory factors and related metabolites after intake of selected herbs, the mechanism behind the warm and cooling effects of specific herbs were revealed.

Mad men, women and steroid cocktails: a review of the impact of sex and other factors on anabolic androgenic steroids effects on affective behaviors

RATIONALE

For several decades, elite athletes and a growing number of recreational consumers have used anabolic androgenic steroids (AAS) as performance enhancing drugs. Despite mounting evidence that illicit use of these synthetic steroids has detrimental effects on affective states, information available on sex-specific actions of these drugs is lacking.

OBJECTIVES

The focus of this review is to assess information to date on the importance of sex and its interaction with other environmental factors on affective behaviors, with an emphasis on data derived from non-human studies.

METHODS

The PubMed database was searched for relevant studies in both sexes.

RESULTS

Studies examining AAS use in females are limited, reflecting the lower prevalence of use in this sex. Data, however, indicate significant sex-specific differences in AAS effects on anxiety-like and aggressive behaviors, interactions with other drugs of abuse, and the interplay of AAS with other environmental factors such as diet and exercise.

CONCLUSIONS

Current methods for assessing AAS use have limitations that suggest biases of both under- and over-reporting, which may be amplified for females who are poorly represented in self-report studies of human subjects and are rarely used in animal studies. Data from animal literature suggest that there are significant sex-specific differences in the impact of AAS on aggression, anxiety, and concomitant use of other abused substances. These results have relevance for human females who take these drugs as performance-enhancing substances and for transgender XX individuals who may illicitly self-administer AAS as they transition to a male gender identity.

Anabolic steroids alter the physiological activity of aggression circuits in the lateral anterior hypothalamus

Syrian hamsters exposed to anabolic/androgenic steroids (AAS) during adolescence consistently show increased aggressive behavior across studies. Although the behavioral and anatomical profiles of AAS-induced alterations have been well characterized, there is a lack of data describing physiological changes that accompany these alterations. For instance, behavioral pharmacology and neuroanatomical studies show that AAS-induced changes in the vasopressin (AVP) neural system within the latero-anterior hypothalamus (LAH) interact with the serotonin (5HT) and dopamine (DA) systems to modulate aggression. To characterize the electrophysiological profile of the AAS aggression circuit, we recorded LAH neurons in adolescent male hamsters in vivo and microiontophoretically applied agonists and antagonists of aggressive behavior. The interspike interval (ISI) of neurons from AAS-treated animals correlated positively with aggressive behaviors, and adolescent AAS exposure altered parameters of activity in regular firing neurons while also changing the proportion of neuron types (i.e., bursting, regular, irregular). AAS-treated animals had more responsive neurons that were excited by AVP application, while cells from control animals showed the opposite effect and were predominantly inhibited by AVP. Both DA D2 antagonists and 5HT increased the firing frequency of AVP-responsive cells from AAS animals and dual application of AVP and D2 antagonists doubled the excitatory effect of AVP or D2 antagonist administration alone. These data suggest that multiple DA circuits in the LAH modulate AAS-induced aggressive responding. More broadly, these data show that multiple neurochemical interactions at the neurophysiological level are altered by adolescent AAS exposure.