The effects of morphine on conditioned suppression in rhesus monkeys

Two rhesus monkeys were exposed to conditioned suppression training in which a 20-sec. stimulus, terminated by unavoidable shock, was superimposed upon a variable interval 90-sec. reinforcement schedule. A concurrent response which had no programmed consequence was recorded during initial variable interval training, acquisition, extinction, and reacquisition of conditioned suppression of the reinforced lever-pressing response. A peak in the distribution of response 2 reliably occurred 30 to 75 sec. following the average lever-pressing (response 1) reinforcement interval. With suppression training, the presentation of the suppression stimulus was reliably followed by a changeover from response 1 to response 2; the presentation of the unavoidable shock immediately resulted in a changeover from response 2 to response 1. The rate of response 2 during the suppression stimulus declined to near zero during extinction of conditioned suppression and increased to a high rate when the suppression stimulus was again terminated by unavoidable shock. The rate of response 2 was dependent upon the intensity of the unavoidable shock.

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The Growth of Herpesvirus mulatto in Human Fibroblast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051232 ◽

1974 ◽

Vol 32 ◽

pp. 244-245

Author(s):

Glennelle Washington ◽

Philip P. McGrath ◽

Peter R. Graze ◽

Ivor Royston

Keyword(s):

Rhesus Monkey ◽

Microscopic Study ◽

Electron Microscopic Study ◽

Peripheral Blood ◽

Human Fibroblast ◽

Rhesus Monkeys ◽

Human Fibroblasts ◽

Electron Microscopic ◽

Specific Antisera ◽

Peripheral Blood Leucocytes

Herpes-like viruses were isolated from rhesus monkey peripheral blood leucocytes when co-cultivated with WI-38 cells. The virus was originally designated rhesus leucocyte-associated herpesvirus (LAHV) and subsequently called Herpesvirus mulatta (HVM). The original isolations were from juvenile rhesus monkeys shown to be free of antibody to rhesus cytomegalic virus. The virus could only be propagated in human or simian fibroblasts. Use of specific antisera developed from HVM showed no relationship between this virus and other herpesviruses. An electron microscopic study was undertaken to determine the morphology of Herpesvirus mulatta (HVM) in infected human fibroblasts.

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Nucleolar Segregation and Chronic Methanol Intoxication

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063718 ◽

1969 ◽

Vol 27 ◽

pp. 360-361

Author(s):

Julio H. Garcia ◽

Janice P. Van Zandt

Keyword(s):

Body Weight ◽

Methyl Alcohol ◽

Rhesus Monkeys ◽

Repeated Administration ◽

Serum Levels ◽

Methanol Intoxication ◽

Intragastric Tube ◽

Nucleolar Segregation

Repeated administration of methyl alcohol to Rhesus monkeys (Maccaca mulata) by intragastric tube resulted in ultrastructural abnormalities of hepatocytes, which persisted in one animal twelve weeks after discontinuation of the methyl alcohol regime. With dosages ranging between 3.0 to 6.0 gms. of methanol per kg. of body weight, the serum levels attained within a few hours averaged approximately 475 mg. per cent.

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Evaluation of hippocampus in rhesus monkeys after chronic (1-year) inhalation exposure to marijuana: I. Electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159539 ◽

1990 ◽

Vol 48 (3) ◽

pp. 398-399

Author(s):

A.M. Andrews ◽

S.W. Wilson ◽

A.C. Scallet ◽

S.F. Ali ◽

J. Bailey ◽

...

Keyword(s):

Synaptic Vesicles ◽

Rhesus Monkeys ◽

Low Dose ◽

Inhalation Exposure ◽

Synaptic Cleft ◽

High Dose ◽

Withdrawal Time ◽

Treatment Groups ◽

Ultrastructural Evidence ◽

Male Rhesus

Exposure of rhesus monkeys (Macaca mulatta) to marijuana via inhalation or to intravenous delta-9-tetrahydrocannabinol (THC), reportedly caused ultrastructural evidence of increased synaptic width. Chronic marijuana smoke in a single rhesus monkey examined after a six month withdrawal time caused ultrastructure changes in the septal, hippocampal and amygdala regions; the synaptic cleft was widened, electron opaque material was found in the cleft and in the pre- and postsynaptic regions, with some clumping of the synaptic vesicles. The objective of our study was to assess neuropathological alterations produced by chronic inhalation of marijuana smoke.Nineteen male rhesus monkeys, 3-5 years of age and weighing 3-8 kg, were divided into four treatment groups: a) sham control, b) placebo smoke (7 days/ week) c) low dose marijuana (2 times/week with 5 days/week sham) and d) high dose marijuana (7 times/week). A smoke exposure consisted of smoke from one cigarette (2.6% THC) burned down to 10 mm butt length. Smoke was administered via smoke generator (ADL II, Arthur D. Little, Inc. Cambridge, MA) and nose-mouth only masks (local production) equipped with one-way valves.

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