Search PubMed⌕ Search

Biomedical subjects

S Gershon

Publications and source records attributed to S Gershon.

At least 199 records · Page 11Linked to original sources

Cardiovascular effects of delta9-tetrahydrocannabinol in conscious and anaesthetized dogs.

1. Temporal effects of delta9-tetrahydrocannabinol (THC) on heart rate and blood pressure in conscious dogs were compared to those in anaesthetized dogs. 2. In conscious dogs, THC in doses of 0.25 and 0.1 mg/kg resulted in maximal heart rate reductions of 48 and 41%, respectively, and in no significant change in blood pressure. 3. In anaesthetized animals THC in doses of 0.5 and 0.25 mg/kg caused a peak reduction in heart rate of 38 and 34%, and of blood pressure of 24 and 8%, respectively. 4. The results demonstrate that the bradycardia in response to THC in dogs is independent of the concomitant anaesthesia. 5. We conclude that the discrepancy between heart rate response to THC in dogs and in man is due to a species difference.

Anesthesia↗

Senile dementia: treatment with deanol.

Recent research indicates a possible cholinergic involvement in memory processes and thus the possibility that acetylcholine deficiency may underlie memory impairment in senile dementia. Deanol (2-dimethylaminoethanol), which is assumed to increase brain acetylcholine, was given openly for 4 weeks to 14 senile outpatients, to determine the safety of the drug and whether or not it reduces cognitive impairment. The dosage was gradually increased to 600 mg three times daily during the first two weeks, with no adverse effects. Ten patients improved globally and 4 were unchanged (p less than .01). The total score on the Sandoz Clinical Assessment-Geriatric (SCAG) was lowered by the third week (p less than .01), primarily as a result of reduced depression, irritability and anxiety, and increased motivation-initiative. However, neither the clinical ratings nor an extensive pre- versus post-treatment series of cognitive tests revealed changes in memory or other cognitive functions. Since a similar separate study with a different compound produced no behavioral changes, it is unlikely that the improvement with deanol was due entirely to placebo effects. The results thus suggest that although deanol may not improve memory, it may produce positive behavioral changes in some senile patients.

Aged↗

Analgesic, heart rate, and temperature effects of delta8-THC during acute and chronic administration to conscious rats.

Acute and chronic effects of delta8-THC on tail-flick, heart rate, and rectal temperature responses in conscious, unrestrained male rats were studied. In the acute experiment unidirectional dose-dependent analgesic, hypothermic, and negative chronotropic cardiac effects were observed within the dose range employed. Of the three variables, heart-rate decreases were most sensitive to the effects of THC, reaching significance at 2 mg/kg. Rapid development of tolerance occurred for all three measures, with complete tolerance developing within 13 days only to the heart-rate decreases. The results discussed in the context of previous data.

Analgesics, Opioid↗

Dopamine receptor alteration in schizophrenia: neuroendocrine evidence.

Growth hormone (hGH) responses to centrally acting dopamine agonists were used as indices of CNS dopaminergic function in order to test hypotheses implicating dopaminergic alteration in the etiopathology of schizophrenia. Apomorphine, a direct acting dopamine receptor agonist, and L-Dopa, an indirect agonist dependent upon presynaptic conversion to dopamine for its action, both elicited elevations in plasma hGH in most young male schizophrenic- and control-subjects. A highly significant difference was seen between the distribution of hGH responses to apomorphine for schizophrenics and that for controls. Unusually high hGH response to apomorphine was seen in schizophrenics who subsequently failed to respond to neuroleptic therapy; intermediate hGH response was seen in controls; and low hGH response was seen in subsequent neuroleptic responders; differences in hGH response were statistically significant for all intergroup comparisons. No such differences were seen between responses of individuals to L-Dopa and to apomorphine. The findings suggest that the variability of hGH response to apomorphine is a reflection of dopamine receptor sensitivity, and that this variability may be an index of non-endocrine related dopaminergic sensitivity. They are consistent with hypotheses relating schizophrenia to alteration in dopamine receptors, although the type of receptor and the direction of alteration may be complex.

Adult↗

Dimethyltryptamine levels in blood of schizophrenic patients and control subjects.

A gas chromatographic-mass spectrometric determination of blood N,N-dimethyltryptamine in normal controls and schizophrenic patients was carried out with a sensitivity limit of 0.05 ng/ml whole blood. Although the results appear to suggest that the mean DMT level was higher in the total patient group, those patients with acute psychosis, female patients and patients with suspiciousness scores on the BPRS of 4 or over, the differences were not statistically significant.

Female↗

Parachlorophenylalanine reversal of tranylcypromine effects in depressed patients.

Hospitalized bipolar and unipolar endogenously depressed patients who showed an antidepressant response to the monoamine oxidase (MAO) inhibitor, tranylcypromine sulfate, relapsed (ie, depression returned) when relatively small doses of parachlorophenylalanine (PCPA) were added for brief periods. Considered together with our findings that PCPA similarly reversed the antidepressant effects of the tricyclic drug, imipramine hydrochloride, implications are (1) serotonergic mechanisms are likely involved in the antidepressant effects of both the tricyclic drugs and MAO inhibitors in man and (2) this indolamine may also play a role in the endogenous clinical state of depression.

Bipolar Disorder↗

Correlation between plasma and cerebrospinal levels of imipramine.

This study measured the levels of imipramine hydrochloride and desipramine hydrochloride (desmethylimipramine) in the plasma and cerebrospinal fluid (CSF) in 11 depressed patients. The oral doses correlated significantly with the plasma levels irrespective of different diagnostic categories. The CSF levels varied significantly. In the endogenous depressive group the CSF levels were significantly higher in responders as compared to nonresponders. The CSF levels of the nonresponders in the endogenous depressive group, and of both responders and nonresponders in the schizo-affective groups, were similar.

Depression↗

Cognitive effects of ACTH 4-10 in the elderly.

The polypeptide ACTH 4-10 has been shown to facilitate learning in animals, and possibly to improve attention and memory in normal human subjects. The purpose of this study was to assess the effects of ACTH 4-10 in cognitively impaired elderly subjects. In a double blind, cross over design, 24 cognitively impaired geriatric outpatients (mean age=71.4, 12 with mild and 12 with severe impairment) received injections of 30 mg or 15 mg ACTH 4-10 or matched placebo on 3 successive days. A cognitive test battery of memory and nonmemory tests was administered each day both before and after treatment. The 30 mg dosage produced a slowing of simple visual RT, a nonsignificant improvement trend in verbal associative memory, and significant, severity dependent facilitation or impairment in day later visual memory. The results suggest that the ACTH 4-10 effects on cognitively impaired elderly are dependent on the dosage and on the baseline cognitive level of the subjects.

Adrenocorticotropic Hormone↗