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D X Freedman

Publications and source records attributed to D X Freedman.

At least 73 records · Page 4Linked to original sources
PubMed1975

Smooth-pursuit eye movements, and diazepam, CPZ, and secobarbital.

This study examined the effects on smooth-pursuit eye tracking of single doses of CPZ (0.667 and 1.334 mg/kg), diazepam (0.071, 0.142, and 0.284 mg/kg), and secobarbital (100 mg). Only the barbiturate significantly affected the ability to follow a moving target with smooth-pursuit eye movements. In repeated testing of a single subject, 130 mg of secobarbital disrupted smooth-pursuit movements at least until 24 hrs after ingestion.

Adult↗
PubMed1975

Effects of single and multiple dose LSD on endogenous levels of brain tyrosine and catecholamines.

The effects on brain catecholamines of seven daily doses of d-LSD 520 mug/kg injected i.p. to Sprague-Dawley rats on a tolerance dosage schedule (L X 7) were compared with the effects of a single dose of LSD (L X 1) 520 mug/kg or 1040 mug/kg, over a 90 min time course. Compared to saline controls, after a single dose of 520 mug/kg LSD, there was a significant decrease in brain norepinephrine at 30 to 60 min, a rise in dopamine at 60 min, and a small rise in brain tyrosine at early time points followed by significant decline from control levels after 60 min. The effects of a single dose of 1040 mug/kg LSD were similar to the 520 mug/kg dose but were greater in both magnitude and duration of the brain catecholamine changes. After a tolerance dosage schedule there were significant changes in the response of brain catecholamines to 520 mug/kg LSD. The rise in brain dopamine at 60 min was abolished, brain tyrosine was uniformly below both saline and L times 1 animals, and brain norepinephrine returned to control levels slightly faster.

Animals↗
PubMed1975

Loss of body weight as a predictor of reserpine-induced amine depletion.

Loss of body weight was proved to be a convenient and reliable way to predict the degree of reserpine-induced amine depletion after i.p. injections of reserpine (2.5, 5 and 10 mg/kg) and it thus helps reduce variability. Two populations of animals were sharply distinguished lying on either side of the 5% cutoff point within the first 24 hr. One group (approximately 20% of all animals) lost less than 5% of their body weight, showed absence of physiological and behavioural effects, a moderate 5-HT depletion and a moderate 5-HIAA increase. These animals were called 'partially reserpinized'. Another group always lost 5% or more of body weight, exhibited the reserpine syndrome as well as a larger extent of 5-HT depletion and 5-HIAA increase. This group comprised 'reserpinized' rats. There were significant correlations between the percent weight loss and the degree of 5-HT depletion and 5-HIAA increase in the group of 'partially reserpinized' animals. The two groups differed also in the time course of amine changes. Dose had no effect in the differentiation of the two groups but did affect the extent of amine depletion. When reserpine was given i.v. or s.c., all animals were 'reserpinized'. The phenomenon of partial reserpinization is discussed.

Animals↗