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D L Cheney

Publications and source records attributed to D L Cheney.

At least 55 records · Page 3Linked to original sources
PubMed1981

Intergroup encounters among free-ranging vervet monkeys.

High-ranking vervet monkeys threatened the members of other groups more than did low-ranking individuals, while only low-ranking females and juvenile males interacted affinitively with the members of other groups. Adult males were most aggressive during intergroup encounters with groups from which males transferred. In contrast, females were most aggressive to groups from which males were not observed to transfer. It is postulated that the behavior of individuals during intergroup encounters may be related to benefits derived from excluding intruders from the group's resources. Furthermore, it seems possible that relations between groups are influenced by previous male transfers, and that female aggression affects the distribution of male movement between groups.

Aggression↗
PubMed1981

The effect of phencyclidine on the turnover rate of acetylcholine in various regions of rat brain.

Although the mechanism of action of phencyclidine is poorly understood, an interaction of phencyclidine with central cholinergic systems has been proposed. To test this hypothesis directly, we investigated the effects of this compound on the turnover rate of acetylcholine (TRACh) in various areas of the rat brain. In doses of 14.3 to 114.4 mumol/kg (i.p.), phencyclidine increased the TRACh in the frontal cortex, parietal cortex and diencephalon when rats were sacrificed 30 min after drug treatment. In contrast, these doses of phencyclidine had no effect on the TRACh in the hippocampus or striatum. The increases in cortical and diencephalic TRACh were temporally correlated with the behavioral activity elicited by phencyclidine. A 7 day chronic treatment regimen (28.6 mumol/kd/day) provided no further evidence for tolerance development to the effects of phencyclidine on the TRACh in the frontal cortex or diencephalon. These results demonstrate that phencyclidine differentially affects cholinergic dynamics in various areas of the rat brain. The neurochemical profile of phencyclidine reported herein is similar to those previously described for central stimulants such as d-amphetamine, nomifensine and cocaine.

Acetylcholine↗
PubMed1980

Monkey responses to three different alarm calls: evidence of predator classification and semantic communication.

Vervet monkeys give different alarm calls to different predators. Recordings of the alarms played back when predators were absent caused the monkeys to run into trees for leopard alarms, look up for eagle alarms, and look down for snake alarms. Adults call primarily to leopards, martial eagles, and pythons, but infants give leopard alarms to various mammals, eagle alarms to many birds, and snake alarms to various snakelike objects. Predator classification improves with age and experience.

Animal Communication↗
PubMed1980

Reduction of hippocampal acetylcholine turnover in rats treated with (-)-delta 8-tetrahydrocannabinol and its 1',2'-dimethyl-heptyl homolog.

The effects of (-)-delta 8-tetrahydrocannabinol (THC), (+)-delta 8-THC, and the dimethyl-heptyl (DMH) homolog of (-)-delta 8-THC (delta 8-THC-DMH) have been compared with the action of (-)-delta 9-THC on the turnover rate of acetylcholine in various brain areas. The data demonstrate that (-)-delta 8-THC-DMH, (-)-delta 9-THC and (-)- delta 8-THC all specifically reduce ther turnover rate of acetylcholine in the hippocampus in a dose-dependent manner ((-)-delta 8-THC-DMH > (-)-delta 9-THC > (-)-delta 8-THC) without altering the acetylcholine or choline content (except for high doses of (-)-delta 8-THC-DMH). The (+)-isomer of delta 8-THC fails to change any cholinergic parameter. The selectivity of action suggests that the tetrahydrocannabinoids may activate specific transmitter receptors which indirectly modulate the activity of the cholinergic neurons in the septal-hippocampal pathway.

Acetylcholine↗
PubMed1979

Cortical lesions modulate turnover rates of acetylcholine and gamma-aminobutyric acid.

Interruption of the cortico-striatal glutamatergic pathway by decoratication results in significant decreases in the turnover rates of acetylcholine TRACh and gamma-aminobutyric acid TRGABA of striatum. These data support the hypothesis that the cortical input to the striatum is excitatory and acts to modulate cholinergic and GABAergic function in this nucleus. Studies of kainate-induced lesions of the striatum also indicate that most striatal cholinergic interneurons receive a glutamatergic input and that multiple injections of kainate are required to destroy this large population of interneurons.

Acetylcholine↗
PubMed1979

The effects of muscarinic receptor blockers on the turnover rate of acetylcholine in various regions of the rat brain.

The actions of antimuscarinic agents (benztropine, trihexyphenidyl, and scopolamine) on the dynamics of acetylcholine (ACh) in central cholinergic neurons were examined in various rat brain areas. It was found that the pattern of changes in ACh turnover (TRACh) elicited by these drugs exhibited marked regional variations. After administration of the anticholinergic drugs, the TRACh in hippocampus and thalamus was increased, in cortex it was decreased, and in striatum it was unchanged. ACh concentration in the cortex and striatum was decreased while in hippocampus and thalamus ACh levels were unaltered. Further analysis of the cholinergic septo-hippocampal pathway using lesions of the fimbria-fornix and local drug injections into the septum argue against an in vivo action of these drugs on presynaptic or cell body muscarinic autoreceptors. Moreover, the data suggest that muscarinic receptor blockers cause an increased TRACh only in those areas where a feedback loop is operative, possibly by inhibiting a neuronal feedback loop involving at least one noncholinergic interneuron.

Acetylcholine↗
PubMed1979

Modulation of the turnover rate of hippocampal acetylcholine by neuropeptides: possible site of action of alpha-melanocyte-stimulating hormone, adrenocorticotrophic hormone and somatostatin.

The intraventricular injection of alpha-melanocyte-stimulating hormone (alpha-MSH), adrenocorticotrophic hormone (ACTH1--24) or somatostatin increases the acetylcholine turnover rate (TRACh) in the hippocampus of rats. Two to 3 weeks after surgical transection of the projections from the cingulum of the entorhinal cortex to the hippocampus the injections of these peptides can still activate hippocampal TRACh. alpha-MSH, ACTH1--24 and somatostatin also increase hippocampal TRACh when injected two to 3 hr after section of the fimbria. In contrast, the intraseptal administration of these peptides fails to change the hippocampal TRACh. The results suggest that the increase in hippocampal TRACh elicited by the three polypeptides may be caused by their interaction with receptors located in the hippocampus. Moreover, the data exclude the possibility that these peptide receptors may be located in septum or in other telencephalic areas that contain neurons projecting to the hippocampus. In addition, this study shows that the septal-hippocampal cholinergic pathway is necessary to elicit a specific stretching-yawning syndrome described by Ferrari et al. (Ann. N.Y. Acad. Sci. 104: 330--345, 1963) after injection of alpha-MSH or ACTH1--24.

Acetylcholine↗
PubMed1978

Modulation of ACh turnover in the septal-hippocampal pathway by electrical stimulation and lesioning.

The septal-hippocampal cholinergic pathway of the rat was either electrically stimulated or lesioned in order to study whether or not acetylcholine turnover rate (TRACh) changes with the activity of the cholinergic neurons. Appropriate electrical stimulation of the septum selectively increased the TRACh in the hippocampus in nonanesthetized and in barbiturate-treated animals. The ACh content of the hippocampus increased by approximately 30% 1 h after fimbria lesions, but decreased by about 80% 9 days after fimbria lesions. Acute fimbria lesions decreased the TRACh in the lesioned side by approximately 85%, but the TRACh in the intact side and in the cortex was unchanged. The same was true in rats with chronic fimbria lesions. In conclusion, the hippocampal TRACh increases or decreases proportionally to the activity of the cholinergic neurons; therefore the measurement of this parameter is of particular value in understanding how postynaptic cholinergic neurons are modulated by putative neurotransmitter released from afferent nerve terminals.

Acetylcholine↗
PubMed1978

Effect of cannabinoids on the turnover rate of acetylcholine in rat hippocampus, striatum and cortex.

The effects of delta9-tetrahydrocannabinol (delta9-THC), the major psychoactive compound of marijuana, and cannabidiol (CBD), a non-psychoactive component, on the acetylcholine (ACh) concentration and the turnover rate of ACh (TRACh) have been studied in various regions of the rat brain. Neither delta9-THC doses from 0.2 to 10 mg/kg nor CBD (10 OR 20 MG/KG) alter the ACh concentration in the brain areas examined 30 min, after the intravenous injection. However, delta9-THC (doses from 0.2 to 10 mg/kg) causes a marked dose-related decrease in the TRACh in hippocampus whereas CBD is without effect in this brain region even when 20 mg/kg is given. Furthermore, high doses of delta9-THC (5 mg/kg) and CBD (20 mg/kg) that produce a significant decrease in the TRACh of striatum fail to change the TRACh in parietal cortex. The low doses of delta9-THC required to reduce hippocampal TRACh suggest that an action on these cholinergic mechanisms may play a role in the psychotomimetic activity of delta9-THC.

Acetylcholine↗