Biomedical subjects

A H Staib

Publications and source records attributed to A H Staib.

At least 73 records · Page 4Linked to original sources

PubMed1976

[Relationships between course of anesthesia, depth of anesthesia and acetylcholine content of the brain after urethane and pentobarbital administration in the rat].

Urethane (1.25 g/kg) and pentobarbital (0.06 g/kg) 30 min after i.v. application increase the content of acetylcholine in telencephalic areas but not in the brain stem. These acetylcholine levels are normalized again 120 min p.i.; but urethane treated animals show an elevated acetylcholine content in the brain stem at this time. A different course of anesthesia by pentobarbital and urethane respectively correlated with this result: Only in the presence of urethane a persistent depression of spontaneous motility was seen, whereas the effectivity of both anesthetics on pinna and corneal reflexes and in respect of pentobarbital also on active movements occurrence declined in the end of the test period.

Acetylcholine↗

PubMed1975

[Tremor following intracerebral carbachol injection. 1.Carbachol sensitivity of various brain structures].

Tremor produced by intracerebral injection of carbachol. I. Susceptibility of different brain areas to carbachol Microinjections of carbachol into the lateral ventricle of rats caused tremor depending on dose. Intensity and duration of motor effects after injection of carbachol (30 mug/3 mul bilateral) into different brain areas were found to depend on localization: strongest tremor was elicited by injections into the nucleus caudatoputamen and cortex cerebri, moderate tremor by administration into the substantia nigra reticularis, globus pallidus and thalamic brain regions. Target areas of mean sensitivity were demonstrated in more rostral and caudal parts of the formatio reticularis. The injection of carbachol into the nucleus ruber, nucleus linearis and substantia nigra compacta brought about lowest tremor values. Ablation of the site of injection from the remaining brain abolished tremor induced by carbachol contrary to the tremor induced by oxotremorine.

Animals↗

PubMed1975

[Cholinergic effect on the dopamine turnover in the rat corpus striatum].

The peripheral administration of oxotremorine caused a significant increase in dihydroxyphenylacetic acid (DOPAC) in the striatum of rats, dopamine (DA) level was unaffected. Injection of oxotremorine into the substantia nigra failed to change the content of dopamine and its acid metabolites homovanillic acid (HVA) and DOPAC in striatum. Injection of oxotremorine or carbachol into the substantia nigra or into the caudate nucleus did not significantly influence the DA-turnover. The partly inconsistent results are discussed in connection with literature data in regard to the existence of excitatory as well as inhibitory cholinergic systems, which are located differently and are involved in the regulation of DA-turnover.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1975

[Effect of various amino acids and their antagonists on the cholinergic tremor and acetylcholine release in the CNS of the rat].

Glycine and GABA administered intraventricularly and intrastriatally were found to inhibit the oxotremorin tremor in rats. The two amino acids reduce both the spontaneous release of acetylcholine into the ventricle and the discharge measured under oxotremorin treatment. The inhibition of the tremor and of acetylcholine release can be blocked by amino acid antagonists (strychnine and picrotoxin), whose effects are not specific for one of these amino acids; this action can be interpreted as effect of interference with other central transmission systems. Structures located close to the ventricles (nigrostriatal path ways) are discussed as possible points of action.

Acetylcholine↗

PubMed1975

Serotonin content in the central nervous system of rats and cholinergic tremor.

Oxotremorine did not alter the level of 5-HT and 5-hydroxyindoleacetic acid in different brain regions. The content of 5-HT in the striatum was diminished by electrolytic lesions of the raphe system, by microinjection of the selective depletor 5,6-dihydroxytryptamine into the raphe system and inhibition of synthesis by pCPA or pCAM. The intensity of oxotremorine-induced tremor was reduced only in some experimental groups without clear-cut correlation to the decreased 5-HT levels. In pCPA-pretreated animals resoring of 5-HT concentration by intrastriatal microinjection of 5-HT and ip administration of 5-HT did not reestablish tremor intensity. There is no evidence that cholinergic tremor is triggered indirectly and depends upon an intact 5-HT system.

Animals↗

PubMed1975