Interactions Between Stress, Ethanol, and THC Exposure and Effects on Prefrontal Reliant Signaling and Behavior

Post-traumatic stress disorder (PTSD) and substance use disorder (SUD) are two highly prevalent and highly debilitating psychological conditions that often occur comorbidly. In accordance with the self-medication hypothesis, drugs like alcohol and cannabis are used following exposure to a traumatic event to acutely reduce anxiety, but, in the long term, these substances cause impairments in learning and memory processes in the prefrontal cortex and reduce the effectiveness of therapeutic treatments for these disorders. As such, the overarching hypothesis of this dissertation is that exposure to stress, alcohol, and cannabis lead to alterations in learning and memory due to modifications in prefrontal cortex signaling, and it is further hypothesized that these impairments can be reversed by normalizing glutamatergic function in this region. These experiments were divided into three main branches of study using behavioral pharmacology as well as optogenetics and fiber photometry to investigate the deleterious effects of stress, cannabis, and alcohol exposure on cognitive functioning and glutamate signaling in the prefrontal cortex. In the first set of studies, restraint stress was followed by set-shifting and alcohol self-administration behavioral tasks to examine stress-induced changes in cognitive flexibility and drug seeking behavior respectively. These experiments established stress induced increases in ethanol seeking and relapse like behavior as well as impairments in cognitive flexibility. The second set of studies established the detrimental effects of alcohol exposure on fear learning during extinction training. Further, this effect was shown to be dependent on glutamatergic activity in the prefrontal cortex using microinjection and optogenetic studies. In the third set of studies, THC vapor and chronic ethanol administration led to deficits in prefrontal cortex reliant behaviors including cognitive flexibility, ethanol seeking, and responses to fear stimuli, and fiber photometry was used to measure effects of these drugs on prefrontal cortex glutamate signaling. Additionally, the pharmaceutical compounds CDPPB and N-acetylcysteine (NAC) were used to pharmacologically reverse the behavioral and signaling impairments that occur as a result of alcohol and cannabis exposure respectively. Taken together, the data presented within this dissertation highlight the effects of alcohol and cannabis on prefrontal cortex-reliant signaling and behavior and use clinically available therapeutics to treat these deficits in a model of PTSD/SUD comorbidity

Free Running Brown Legs

Senior Project submitted to The Division of Languages and Literature of Bard College

Plant Beds

Due to the occurrence of blue mold and manganese toxicity in some of the plant beds this last spring, it is probably advisable for all growers to select a new site for the 1964 crop. Blue mold is a fungus disease which sometimes causes severe damage to tobacco seedings just prior to setting time. The fungus will produce heavy-walled spores on the dying or dead leaves. These spores are capable of remaining in the soil at least a year and attacking the next crop of plants if the same site is used again for tobacco plants

A New Black Shank Resistant Hybrid

Seed of a new black shank resistant burley hybrid will be available to growers in 1964. This hybrid is especially for farmers who cannot rotate their tobacco land and . thus, are forced to set their crop in a black shank infested field. The hybrid is a cross between two black shank resistant varieties, MS L8 and Burley 37. The female parent , MS L8, carries black shank resistance from a wild relative of tobacco

Organic Toxicity

In recent years there has been much discussion on the subject of organic matter toxicity and its relation to the severity of black root rot of tobacco. Organic matter toxicity is due to or at least related to toxins produced during organic matter decomposition

The Organs of the Parietal Fossa in Elasmobranchs

Davidson, in a paper on the musculature of Heptanchus maculatus (1918), mentions a small shield-shaped organ to be found in the parietal fossa, and in connection with it a pair of small muscles having their origin on the cranium and dorsal longitudinal muscles. He believes that these muscles constrict this sac-like organ

Fall Treatment of Tobacco Beds with Methyl Bromide

Treating tobacco beds with methyl bromide for the purpose of killing weed seed has become very popular in recent years. The gas is effective except on the seed of white clover and when the soil temperature is below 50° F

Calcium Deficiency Symptoms in Burley Tobacco

Calcium is an element required by all higher plants in relatively large quantities. It appears to be closely related to the formation of buds and flowers. Calcium is usually available in sufficient quantities in Kentucky soils to produce a normal crop of tobacco. However, when certain varieties of burley tobacco commence to bloom and produce suckers, the tips of the calyx lobes of the flowers may turn brown and die and the edges of the small leaves of the suckers may be necrotic, resulting in irregularly shaped sucker leaves. In severe cases the apical bud may be killed. These calcium deficiency symptoms are most often observed during periods of stress such as protracted dry periods. This condition has been found to be heritable and is apparently caused by the improper utilization by the plant rather than the lack of calcium in the soil