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Glucagon-like peptide 1 (GLP-1) receptor agonists can decrease alcohol intake by central mechanisms that are still poorly understood. The lateral septum (LS) and the ventral/caudal part of the hippocampus are enriched in GLP-1 receptors, and activity in these regions was shown to modulate reward-related behaviors. Using microinfusions of the GLP-1 receptor agonist exendin-4 in mice trained to self-administer oral alcohol in an operant assay, we tested whether pharmacological stimulation of GLP-1 receptors in hippocampus and LS decrease alcohol self-administration. We report that infusion of exendin-4 in the ventral hippocampus or LS was sufficient to reduce alcohol self-administration with as large effect sizes as we previously reported with systemic exendin-4 administration. Infusion of exendin-4 into the nucleus accumbens also reduced alcohol self-administration, as anticipated based on earlier reports, while infusion of exendin-4 into the caudate-putamen (dorsal striatum) had little effect, consistent with lack of GLP-1 receptor expression in this region. The distribution of exendin-4 after infusion into the LS or caudate putamen was visualized using a fluorescently labeled ligand. These findings add to our understanding of the circuit-level mechanisms underlying the ability of GLP-1 receptor agonists to reduce alcohol self-administration., Glucagon-like peptide 1 (GLP-1) receptor agonists can decrease alcohol intake by central mechanisms that are still poorly understood. The lateral septum (LS) and the ventral/caudal part of the hippocampus are enriched in GLP-1 receptors, and activity in these regions was shown to modulate reward-related behaviors. Using microinfusions of the GLP-1 receptor agonist exendin-4 in mice trained to self-administer oral alcohol in an operant assay, we tested whether pharmacological stimulation of GLP-1 receptors in hippocampus and LS decrease alcohol self-administration. We report that infusion of exendin-4 in the ventral hippocampus or LS was sufficient to reduce alcohol self-administration with as large effect sizes as we previously reported with systemic exendin-4 administration. Infusion of exendin-4 into the nucleus accumbens also reduced alcohol self-administration, as anticipated based on earlier reports, while infusion of exendin-4 into the caudateputamen (dorsal striatum) had little effect, consistent with lack of GLP-1 receptor expression in this region. The distribution of exendin-4 after infusion into the LS or caudate putamen was visualized using a fluorescently labeled ligand. These findings add to our understanding of the circuit-level mechanisms underlying the ability of GLP-1 receptor agonists to reduce alcohol self-administration.

Includes bibliographical references (pages 71-96)., Includes abstract.

Dependence on opioids and the number of opioid overdose deaths are serious and escalating public health problems, but medication-assisted treatments for opioid addiction remain inadequate for many patients. Glucagon-like pepide-1 (GLP-1) is a gut hormone and neuropeptide with actions in peripheral tissues and in the brain, including regulation of blood glucose and food intake. GLP-1 analogs, which are approved diabetes medications, can reduce the reinforcing and rewarding effects of alcohol, cocaine, amphetamine, and nicotine in rodents. Investigations on effects of GLP-1 analogs on opioid reward and reinforcement have not been reported. We assessed the effects of the GLP-1 receptor agonist Exendin-4 (Ex4) on opioid-related behaviors in male mice, i.e., morphine-conditioned place preference (CPP), intravenous self-administration (IVSA) of the short-acting synthetic opioid remifentanil, naltrexone-precipitated morphine withdrawal, morphine analgesia (male and female mice), and locomotor activity. Ex4 treatment had no effect on morphine-induced CPP, withdrawal, or hyperlocomotion. Ex4 failed to decrease remifentanil self-administration, if anything reinforcing effects of remifentanil appeared increased in Ex4-treated mice relative to saline. Ex4 did not significantly affect analgesia. In contrast, Ex4 dose dependently decreased oral alcohol self-administration, and suppressed spontaneous locomotor activity. Taken together, Ex4 did not attenuate the addiction-related behavioral effects of opioids, indicating that GLP-1 analogs would not be useful medications in the treatment of opioid addiction. This difference between opioids and other drug classes investigated to date may shed light on the mechanism of action of GLP-1 receptor treatment in the addictive effects of alcohol, central stimulants, and nicotine.

Dependence on opioids and the number of opioid overdose deaths are serious and escalating public health problems, but medication-assisted treatments for opioid addiction remain inadequate for many patients. Glucagon-like pepide-1 (GLP-1) is a gut hormone and neuropeptide with actions in peripheral tissues and in the brain, including regulation of blood glucose and food intake. GLP-1 analogs, which are approved diabetes medications, can reduce the reinforcing and rewarding effects of alcohol, cocaine, amphetamine, and nicotine in rodents. Investigations on effects of GLP-1 analogs on opioid reward and reinforcement have not been reported. We assessed the effects of the GLP-1 receptor agonist Exendin-4 (Ex4) on opioid-related behaviors in male mice, i.e., morphine-conditioned place preference (CPP), intravenous self-administration (IVSA) of the short-acting synthetic opioid remifentanil, naltrexone-precipitated morphine withdrawal, morphine analgesia (male and female mice), and locomotor activity. Ex4 treatment had no effect on morphine-induced CPP, withdrawal, or hyperlocomotion. Ex4 failed to decrease remifentanil self-administration, if anything reinforcing effects of remifentanil appeared increased in Ex4-treated mice relative to saline. Ex4 did not significantly affect analgesia. In contrast, Ex4 dose dependently decreased oral alcohol self-administration, and suppressed spontaneous locomotor activity. Taken together, Ex4 did not attenuate the addiction-related behavioral effects of opioids, indicating that GLP-1 analogs would not be useful medications in the treatment of opioid addiction. This difference between opioids and other drug classes investigated to date may shed light on the mechanism of action of GLP-1 receptor treatment in the addictive effects of alcohol, central stimulants, and nicotine.

Cocaine administration has been shown to produce immediate positive (rewarding) and subsequent negative (anxiogenic) effects in humans and animals. These dual and opposing affective responses have been more difficult to demonstrate with administration of methamphetamine (meth). While animal studies have reliably demonstrated the positive reinforcing effects of the drug, reports of negative aftereffects following acute exposure have been few in number and contradictory in nature. The current research was devised to assess the effects of acute meth using a runway model of self-administration that is uniquely sensitive to both the positive and negative effects of a drug reinforcer in the same animal on the same trial. Male rats were allowed to traverse a straight alley once a day for 16 consecutive days/trials where entry into the goal box resulted in a single IV injection of meth (0.25, 0.5 or 1.0 mg/kg/inj.). The chosen doses were confirmed to be psychoactive as they produced dose-dependent increases in motoric/locomotor activation in these same subjects. The results demonstrated a U-shaped dose-response curve for the reinforcing effects of meth in that the intermediate dose group (0.5 mg/kg) produced the strongest approach behavior in the runway. Unlike other psychomotor stimulants, like cocaine, animals running for IV meth exhibited no evidence of any significant approach-avoidance behaviors reflective of the drug's negative anxiogenic effects. These results suggest that the abuse potential for meth is likely higher than for other shorter-acting psychomotor stimulants and reaffirms the utility of the runway procedure as a screen for a substance's abuse potential.

Chemotherapy-induced peripheral neuropathy (CIPN) is a severe and dose-limiting side effect of cancer treatment that affects millions of cancer survivors throughout the world and current treatment options are extremely limited by their side effects. Cannabinoids are highly effective in suppressing pain symptoms of chemotherapy-induced and other peripheral neuropathies but their widespread use is limited by central nervous system (CNS)-mediated side effects. Here, we tested one compound from a series of recently developed synthetic peripherally restricted cannabinoids (PRCBs) in a rat model of cisplatin-induced peripheral neuropathy. Results show that local or systemic administration of 4-{2-[-(1E)-1[(4-propylnaphthalen-1-yl)methylidene]-1H-inden-3-yl]ethyl}morpholine (PrNMI) dose-dependently suppressed CIPN mechanical and cold allodynia. Orally administered PrNMI also dose-dependently suppressed CIPN allodynia symptoms in both male and female rats without any CNS side effects. Co-administration with selective cannabinoid receptor subtype blockers revealed that PrNMIs anti-allodynic effects are mediated by CB1 receptor (CB1R) activation. Expression of CB2Rs was reduced in dorsal root ganglia from CIPN rats, whereas expression of CB1Rs and various endocannabinoid synthesizing and metabolizing enzymes was unaffected. Daily PrNMI treatment of CIPN rats for two weeks showed a lack of appreciable tolerance to PrNMIs anti-allodynic effects. In an operant task which reflects cerebral processing of pain, PrNMI also dose-dependently suppressed CIPN pain behaviors. Our results demonstrate that PRCBs exemplified by PrNMI may represent a viable option for the treatment of CIPN pain symptoms.

Chemotherapy-induced peripheral neuropathy (CIPN) is a severe and dose-limiting side effect of cancer treatment that affects millions of cancer survivors throughout the world and current treatment options are extremely limited by their side effects. Cannabinoids are highly effective in suppressing pain symptoms of chemotherapy-induced and other peripheral neuropathies but their widespread use is limited by central nervous system (CNS)-mediated side effects. Here, we tested one compound from a series of recently developed synthetic peripherally restricted cannabinoids (PRCBs) in a rat model of cisplatin-induced peripheral neuropathy. Results show that local or systemic administration of 4-{2-[-(1E)-1[(4-propylnaphthalen-1-yl)methylidene]-1H-inden-3-yl]ethyl}morpholine (PrNMI) dose-dependently suppressed CIPN mechanical and cold allodynia. Orally administered PrNMI also dose-dependently suppressed CIPN allodynia symptoms in both male and female rats without any CNS side effects. Co-administration with selective cannabinoid receptor subtype blockers revealed that PrNMI's anti-allodynic effects are mediated by CB1 receptor (CB1R) activation. Expression of CB2Rs was reduced in dorsal root ganglia from CIPN rats, whereas expression of CB1Rs and various endocannabinoid synthesizing and metabolizing enzymes was unaffected. Daily PrNMI treatment of CIPN rats for two weeks showed a lack of appreciable tolerance to PrNMI's anti-allodynic effects. In an operant task which reflects cerebral processing of pain, PrNMI also dose-dependently suppressed CIPN pain behaviors. Our results demonstrate that PRCBs exemplified by PrNMI may represent a viable option for the treatment of CIPN pain symptoms.

Anabolic-androgenic steroid (AAS) abuse is implicated in maladaptive decision making such as increased risk taking and problem gambling. Endogenous testosterone correlates with economic risk taking in both the stock market (Coates & Herbert, 2008) and in the laboratory, as measured by the Iowa Gambling Task (Stanton, Liening, & Schultheiss, 2011). Additionally, AAS use has been associated with problem gambling behavior in adolescents (Proimos, DuRant, Pierce, & Goodman, 1998). Thus, AAS may impair economic decision making. However, studies of human AAS users cannot control for preexisting risky behavior or normalize androgen levels. Accordingly, the present study investigated AAS effects on decision making in rats using a novel, balanced rodent model of the IGT. Adolescent male Long-Evans rats were treated chronically with high-dose testosterone (7.5 mg/kg) or vehicle (13% cyclodextrin in water) sc, and trained to work for sugar pellets in an operant chamber equipped with 4 levers, each associated with a different schedule of reward magnitude (number of pellets), probability, and punishment (time-out) duration. By RM-ANOVA, there was a main effect of lever (F-3,F-78 = 25.33, p < .05), such that all rats preferred lever L4 offering a large reward (4 pellets), but with low probability (45%) and a long (35 sec) time-out. There was also a significant interaction of testosterone x lever (F-3,F-78 = 2.78, p < .05), with testosterone increasing preference for L4 and decreasing preference for the other levers, relative to vehicle-treated controls. These data extend our previous findings of altered decision making in AAS-treated rats, and suggest that AAS may alter economic decision making in human users.

Anabolic-androgenic steroid abuse is implicated in maladaptive behaviors such as impaired cognition in humans. In a rat model, our lab has shown that testosterone decreases preference for a large/uncertain reward in probability discounting. Other studies have shown that androgens decrease dopamine D1 and D2 receptors in the nucleus accumbens shell, a region important for decision-making behavior in probability discounting. Thus, we attempted to restore selection of the large/uncertain reward in testosterone-treated rats by administering the D2 receptor agonist quinpirole or the D1 receptor agonist SKF81297 and testing probability discounting. Adolescent male Long-Evans rats were treated chronically with high-dose testosterone (7.5 mg/kg) or vehicle (13% cyclodextrin in water), and tested for probability discounting after injections of saline, 0.1 and 0.5 mg/kg of quinpirole or SKF81297. Rats chose between a small/certain reward (1 sugar pellet, 100% probability) and a large/uncertain reward (4 pellets, decreasing probability: 100, 75, 50, 25, 0%). Testosterone-treated rats selected the large/uncertain reward significantly less than vehicle-treated controls after saline injection. However, acute injection with 0.1 mg/kg quinpirole increased large/uncertain reward preference in testosterone-treated rats only, indicated by a testosterone x quinpirole interaction. At 0.5 mg/kg, quinpirole increased large/uncertain reward preference in all rats. Acute injection with SKF81297 at 0.1 or 0.5 mg/kg rescued large/uncertain reward preference in testosterone-treated rats by eliminating the difference between groups. It appears that altered probability discounting behavior in testosterone-treated rats is due to both decreased D1 and D2 receptor function.

Chemotherapy-induced peripheral neuropathy (CIPN) is a severe and dose-limiting side effect of cancer treatment that affects millions of cancer survivors throughout the world and current treatment options are extremely limited by their side effects. Cannabinoids are highly effective in suppressing pain symptoms of chemotherapy-induced and other peripheral neuropathies but their widespread use is limited by central nervous system (CNS)-mediated side effects. Here, we tested one compound from a series of recently developed synthetic peripherally restricted cannabinoids (PRCBs) in a rat model of cisplatin-induced peripheral neuropathy. Results show that local or systemic administration of 4-{2-[-(1E)-1[(4-propylnaphthalen-1-yl)methylidene]-1H-inden-3-yl]ethyl}morpholine (PrNMI) dose-dependently suppressed CIPN mechanical and cold allodynia. Orally administered PrNMI also dose-dependently suppressed CIPN allodynia symptoms in both male and female rats without any CNS side effects. Co-administration with selective cannabinoid receptor subtype blockers revealed that PrNMI's anti-allodynic effects are mediated by CB1 receptor (CB1R) activation. Expression of CB2Rs was reduced in dorsal root ganglia from CIPN rats, whereas expression of CB1Rs and various endocannabinoid synthesizing and metabolizing enzymes was unaffected. Daily PrNMI treatment of CIPN rats for two weeks showed a lack of appreciable tolerance to PrNMI's anti-allodynic effects. In an operant task which reflects cerebral processing of pain, PrNMI also dose-dependently suppressed CIPN pain behaviors. Our results demonstrate that PRCBs exemplified by PrNMI may represent a viable option for the treatment of CIPN pain symptoms.

Volition has been debated for thousands of years:  what is it, how is it possible for biophysical beings to behave in a voluntary manner, indeed, does volition exist?  Evolution of volition has rarely been part of the discussion.  In this paper, I argue that operant-conditioning studies provide evidence for evolved volition.  Three attributes are common to operant and voluntary behaviors.  One is that responses are goal-directed, purposeful, some say rational, or controlled by reinforcing consequences.  A second is that the responses vary – from random-like to repetitive – with predictability (or unpredictability) depending upon contexts and consequences.  A third attribute is that responses appear to be self-generated or, in operant terms, emitted.  These attributes are found in many species, simple to complex, but species also differ in details.  Taken together, the evidence supports an evolutionary basis of volition.

Volition has been debated for thousands of years: what is it, how is it possible for biophysical beings to behave in a voluntary manner, indeed, does volition exist? Evolution of volition has rarely been part of the discussion. In this paper, I argue that operant-conditioning studies provide evidence for evolved volition. Three attributes are common to operant and voluntary behaviors. One is that responses are goal-directed, purposeful, some say rational, or controlled by reinforcing consequences. A second is that the responses vary – from random-like to repetitive – with predictability (or unpredictability) depending upon contexts and consequences. A third attribute is that responses appear to be self-generated or, in operant terms, emitted. These attributes are found in many species, simple to complex, but species also differ in details. Taken together, the evidence supports an evolutionary basis of volition.

The development and deployment of next-generation therapeutics to protect military and civilian personnel against chemical warfare nerve agent threats require the establishment and validation of animal models., The original document contains color images. Pub. in Pharmacology, Biochemistry and Behavior, v100 n3 p382-391, 2012.

This study attempts to experimentally manipulate core constructs of the Health Belief Model (HBM) and the Theory of Planned Behavior (TPB) in order to increase condom use behavior. A direct comparison of the two models to determine the theory that best explains condom use behavior change will also be attempted. University of New Mexico psychology students (N = 280) completed measures on perceived susceptibility, severity, benefits, barriers, condom use self-efficacy, attitudes toward condoms, subjective norms, and perceived behavioral control. Next, they completed one of three randomly assigned computer-based interventions. 218 (77.8%) completed a behavioral assessment one month later. The TPB was best at explaining risky sexual behavior at baseline; it explained 30.6% of the variance while the HBM only explained 1.5% of the variance. The interventions were able to manipulate every predictor but perceived barriers. Mediational analyses of the HBM revealed that intervention type had an effect on perceived susceptibility, benefits, barriers, and condom use self-efficacy, but none of these mediators predicted risky sexual behavior at follow-up. TPB mediators attitudes toward condom use and subjective norms were influenced by intervention type. Subjective norms and perceived behavioral control predicted intentions, but intentions did not predict behavior at follow-up. This study supports the assertion that theory-based interventions are more effective at changing proposed mediators of behavior; however, it was not successful at eliciting behavior change. In sum, current behavior theories should be rigorously examined and modified if need be to create more comprehensive theories of behavior change.

This study attempts to experimentally manipulate core constructs of the Health Belief Model (HBM) and the Theory of Planned Behavior (TPB) in order to increase condom use behavior. A direct comparison of the two models to determine the theory that best explains condom use behavior change will also be attempted. University of New Mexico psychology students (N = 280) completed measures on perceived susceptibility, severity, benefits, barriers, condom use self-efficacy, attitudes toward condoms, subjective norms, and perceived behavioral control. Next, they completed one of three randomly assigned computer-based interventions. 218 (77.8%) completed a behavioral assessment one month later. The TPB was best at explaining risky sexual behavior at baseline; it explained 30.6% of the variance while the HBM only explained 1.5% of the variance. The interventions were able to manipulate every predictor but perceived barriers. Mediational analyses of the HBM revealed that intervention type had an effect on perceived susceptibility, benefits, barriers, and condom use self-efficacy, but none of these mediators predicted risky sexual behavior at follow-up. TPB mediators attitudes toward condom use and subjective norms were influenced by intervention type. Subjective norms and perceived behavioral control predicted intentions, but intentions did not predict behavior at follow-up. This study supports the assertion that theory-based interventions are more effective at changing proposed mediators of behavior; however, it was not successful at eliciting behavior change. In sum, current behavior theories should be rigorously examined and modified if need be to create more comprehensive theories of behavior change.

English: South Africa is considered to be one of the countries with the highest crime rate in the world. It is disturbing to note that a large percentage of these crimes are perpetrated against children. A culture of violence seems to be the norm within the South African community. The demise of apartheid and the transition to a post-apartheid socio-political dispensation has had a serious psychological impact on South African children. Unless drastic measures are taken to bring about change, more and more children will be presenting with stress related symptoms and problems connected to age-related developmental tasks. Children are especially vulnerable during middle childhood and the possibility exists that the demands they are subjected to, will overwhelm them both emotionally and psychologically. The purpose of this study is to develop and implement a stress resilience program to promote children’s ability to manage stress. The goal of the recent study is to scientifically evaluate the resilience program in order to determine its contribution to children’s ability to manage stress. Thus post testing was carried out immediately after the completion of the program. Follow-up tests were carried out three months after completion to determine the medium term effect. A total of 168 children between the ages of 11 and 12 (Grade 6) were involved in this research. The simple random sampling applied in each school did not provide sufficient participants; therefore an availability study was used. The participants were divided into simple experimental- and control groups. The Solomon Four Group Design was used. As a result two experimental and two control groups were formed from the random sampling. Only one experimental group and one control group were subjected to the pre-testing. Both the experimental groups and control groups (four groups) were subjected to post-testing as well as a three month follow-up test. At the conclusion of the program it was presented to the con, Afrikaans: Suid-Afrika word beskou as een van die lande met die hoogste misdaadsyfers ter wêreld. Dit is kommerwekkend dat ‘n groot persentasie van hierdie misdade verband hou met misdade teen kinders. Daar word algemeen verwys na die “kultuur van geweld” as normatief binne die Suid-Afrikaanse gemeenskap. Die einde van apartheid en die oorgang na ‘n post-apartheid sosio-politiese bestel het ook ‘n ernstige sielkundige impak gehad op Suid-Afrikaanse kinders. Indien daar nie drasties ‘n verandering plaasvind nie, sal kinders al meer presenteer met stresverwante simptome en probleme met die bemeestering van ouderdomstoepaslike ontwikkelingstake. Die middelkinderjare is ‘n betreklike kwesbare stadium en die moontlikheid bestaan dat kinders emosioneel en sielkundig oorweldig kan word deur al die eise wat aan hulle gestel word. Die doel van die studie is om ‘n stresweerbaarheidsprogram te ontwikkel en te implementeer ten einde kinders se stresweerbaarheid te bevorder. Die huidige studie het ook ten doel om die stresweerbaarheidsprogram op ‘n wetenskaplike wyse te evalueer om sodoende die bydrae van die program tot kinders se stresweerbaarheid te bepaal. Gevolglik is ‘n natoetsing direk na die afloop van die program voltooi. ‘n Opvolgtoetsing is drie maande na die program voltooi om sodoende ook die mediumtermyn-effek van die program te bepaal. ‘n Totaal van 168 kinders tussen die ouderdomme van 11 en 12 jaar (Graad 6) is in die ondersoek ingesluit. Aangesien die ewekansige streekproeftrekking in elke skool nie genoeg deelnemers opgelewer het nie, is daar van ‘n beskikbaarheidsteekproef gebruik gemaak. Hierdie deelnemers is ewekansig in eksperimentele- en kontrolegroepe verdeel. Die Solomon viergroepontwerp is gebruik. Hiervolgens is twee eksperimentele groepe en twee kontrolegroepe gevorm vanuit die steekproef. Een eksperimentele groep en een kontrolegroep is aan die voortoetsing onderwerp. Beide die eksperimentele en kontrolegroepe is aan die natoetsing, sowel as die dri

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This study evaluated the dose-response effects of subacute exposure to sublethal doses of VX on acoustic startle response (ASR) and operant behavior of rats. ASR baseline was established and rats were exposed to 2 consecutive daily doses of fractions (0.2, 0.4, and 0.6) of the established LD50 of VX (16 micrograms/kg). ASR testing continued for 4 days post-exposure. Subsequently animals were dietary restricted and trained to lever press for food under an autoshaping procedure; then a series of escalating fixed ratio (FR) schedules was introduced. Four sessions were conducted under a differential reinforcement of low response rate 10? (DRL 10 s) schedule. Performance under an ascending and descending series of geometric progressive ratio schedules was evaluated. VX decreased the magnitude of ASR on injection days to 100-dB pulses for all exposed groups and to 120-dB pulses only for the 0.4 and 0.6 LD50 groups. VX increased the latency to peak startle magnitude in animals receiving 0.4 and 0.6 LD50 on injection days. There were no significant dose-related effects on prepulse inhibition and no significant dose-related differences on the acquisition of lever pressing via autoshaping, lever pressing under escalating FR schedules, responding under DRL 10 s schedules of reinforcement, nor responding under geometric progressive ratio schedules. These data indicate few persistent effects of subacute VX exposure on the acquisition of operant behavior., The original document contains color images.

Learning to perform instrumental tasks is an ability of all animals. In a population of rats, not all individuals will acquire an operant response for reward. We hypothesized that there could be a genetic explanation for differences between High Consumers (those that acquired the lever press response) and Low Consumers (lever press response is low). Additionally, we proposed that this genetic difference could produce measurable changes in response to novelty. Wistar rats were trained to lever press for a 0.2% saccharin reward and on the 10th day they were placed in a novel open field for 30 min to record locomotor activity. The prefrontal cortex and hippocampus were dissected and qPCR was used to measure mRNA expression. A significant difference (p=.048; 2-way ANOVA) in gene expression was observed between Low and High Consumers. A principal component analysis (PCA), to cluster which genes represent this difference, identified 4 genes; 5-HT2A and mGlu1 in the hippocampus and AMPA GluR1 and adrenergic alpha2A in the prefrontal cortex. Response to a novel open field also differed since Low Consumers displayed a higher Total Distance in comparison to High Consumers. Additionally, Low Consumers could be subdivided into Low-Lever (with lever press response only when water deprived) and Low-Non-Lever (lever press response is low throughout training). PCA with this subdivision identified an additional nine genes differing within the divisions; NMDA NR2B and GABAAalpha3 in the prefrontal cortex and adrenergic alpha2B and alpha2A, AMPA GluR1, GluR2 and GluR3, 5-HT1B and GABAAalpha5 in the hippocampus.

Rationale: Anabolic steroids are drugs of abuse. However, the potential for addiction remains unclear. Testosterone induces conditioned place preference in rats and oral self-administration in hamsters. Objectives: To determine if male rats and hamsters consume testosterone by intravenous (IV) or intracerebroventricular (ICV) self- administration. Methods: With each nose-poke in the active hole during daily 4-h tests in an operant condi- tioning chamber, gonad-intact adult rats and hamsters received 50 mg testosterone in an aqueous solution of b-cyclodextrin via jugular cannula. The inactive nose- poke hole served as a control. Additional hamsters received vehicle infusions. Results: Rats (n=7) expressed a significant preference for the active nose-poke hole (10.0€2.8 responses/4 h) over the inactive hole (4.7€1.2 responses/4 h). Similarly, during 16 days of testosterone self-administration IV, hamsters (n=9) averaged 11.7€2.9 responses/4 h and 6.3€1.1 responses/4 h in the active and inactive nose-poke holes, respectively. By contrast, vehicle controls (n=8) failed to develop a preference for the active nose-poke hole (6.5€0.5 and 6.4€0.3 responses/4 h). Hamsters (n=8) also self-administered 1 mg testosterone ICV (active hole:39.8€6.0 nose-pokes/ 4 h; inactive hole: 22.6€7.1 nose-pokes/4 h). When testosterone was replaced with vehicle, nose-poking in the active hole declined from 31.1€7.6 to 11.9€3.2 responses/ 4 h within 6 days. Likewise, reversing active and inactive holes increased nose-poking in the previously inactive hole from 9.1€1.9 to 25.6€5.4 responses/4 h. However, reducing the testosterone dose from 1 mg to 0.2 mg per 1 ml injection did not change nose-poking. Conclu- sions: Compared with other drugs of abuse, testosterone reinforcement is modest. Nonetheless, these data support the hypothesis that testosterone is reinforcing.

Thesis (M.A.)--Florida Atlantic University, 1975., Summary: Parametric manipulation of Sidman avoidance produced different kinds of performances in subjects, which were tested while under amphetamine treatment. The results were found to be incompatible with the principles of the stimulus control theory of Weiss and Laties as well as other general and particular explanations of the drug's effect. An explanation was suggested in terms of general arousal and individual differences.

A large variety of microwave producing devices are used in contemporary naval communications and weapons systems. Public and scientific concern about potential biological effects of microwave irradiation such as produced by these various devices requires documentations of such effects. Currently, the only well documented direct effect of microwaves is heating of the exposed organism. The present report is of a series of studies whose aim was to explore several microwave frequencies and their effect on performance and simultaneously to investigate the relationship to core heating in the exposed animals. Three difficult sized species of animals were used so that generalization to larger animals could be made. Rats, squirrel monkeys, and rhesus monkeys showed consistent effects of 60-minute exposures to microwaves when their body temperatures were increased at least 1 C above baseline temperatures. Performance was not reliably affected when body temperatures remained below this level. Greater intensities of microwaves were required to influence the animals' temperature and behavior as the animal size increased. A direct relationship between frequency and power density was observed in the rhesus monkey; e. g., as the frequency of the microwaves increased, the power density needed to affect behavior and temperature also increased.