Sex differences in basal and cocaine-induced alterations in PKA and CREB proteins in the nucleus accumbens.

Introduction: Alterations in protein kinase (PKA) protein levels have been implicated in the regulation of responses to and development of cocaine addiction. However, the contribution of differences in PKA intracellular cascade to the known sex differences in responses to cocaine is not well understood. This study examined whether there are intrinsic or cocaine-induced alterations in PKA-mediated responses, such as phosphorylation of cyclic AMP response element binding protein, in male and female rats.

Testosterone plays a limited role in cocaine-induced conditioned place preference and locomotor activity in male rats.

Growing evidence suggests that sex differences in cocaine reward responses are regulated by endogenous gonadal hormones. However, few studies have addressed the role of testosterone on cocaine reward and psychomotor activation. This study aimed to determine whether testosterone influences the development of psychomotor and reward responses to cocaine.

Cocaine-induced sex differences in D1 receptor activation and binding levels after acute cocaine administration.

Although it is established that female rats have a more robust behavioral response to acute cocaine administration than male rats, the neurobiological mechanisms underlying these differences remain unclear. The purpose of the present study was to determine whether dopamine (DA) receptor activation influences sex differences in cocaine-induced behaviors. A second study was performed to determine sex differences in D1/D2 receptor levels prior to and post-cocaine administration.

Estradiol administration mediates the inflammatory response to formalin in female rats.

Female rats demonstrate higher pain sensitivity than do males in various nociceptive assays of inflammation. In the present study, we found that estradiol (20%) replacement in ovariectomized rats attenuated the chronic phase of the formalin response but only at high formalin concentrations thought to rely on peripheral inflammation. An inactive isomer of estradiol, alpha-estradiol, failed to result in the same attenuation (P > 0.

Sex differences in cocaine-induced behavioral responses, pharmacokinetics, and monoamine levels.

Female rats display a more robust behavioral response to acute cocaine administration than do male rats. However, a clear understanding of the biological mechanisms underlying these differences remains elusive. The present study investigated whether sexual dimorphisms in cocaine-induced motor behavior might be based on monoaminergic levels and/or cocaine pharmacokinetics.

Sex differences in the conditioned rewarding effects of cocaine.

Several recent reports have demonstrated sex differences in the behavioral and neurochemical response to cocaine. However, it is not clear whether differences exist in cocaine reward or the extent to which adrenal hormones regulate cocaine-induced conditioned place preference (CPP) in either sex. To address these questions, side-by-side comparisons were conducted to determine the effects of conditioning length, cocaine dose and adrenalectomy on cocaine CPP in male and female rats.